WO2005009934A2 - Two-stage hydroformylation - Google Patents

Abstract

The invention relates to a method for production of hydroformylated olefins, whereby a) an olefin-containing feed, carbon monoxide and hydrogen are fed into a first reaction zone and reacted in the presence of a first catalyst system, b) a liquid stream essentially comprising unreacted olefins and optionally saturated hydrocarbons is separated from the discharge from the first reaction zone, c) the liquid stream obtained in step b), carbon monoxide and hydrogen are fed into a second reaction zone and reacted in the presence of a second catalyst system.

Description

Two-stage hydroformylation process

description

The present invention relates to a process for the preparation of hydroformylation products of olefins, in which an olefin-containing feed is reacted in a first reaction zone in the presence of a first catalyst system, a stream containing the unreacted olefins is separated from the discharge from the first reaction zone and the latter is separated in a second reaction zone in the presence of a second catalyst system. The invention further relates to a process for the preparation of 2-propylheptanol, which comprises such a hydroformylation.

Hydroformylation or oxo synthesis is an important large-scale process and is used to produce aldehydes from olefins, carbon monoxide and hydrogen. These aldehydes can optionally be hydrogenated in the same operation with hydrogen to the corresponding oxo alcohols. The reaction itself is highly exothermic and generally takes place under elevated pressure and at elevated temperatures in the presence of catalysts. Co, Rh, Ir, Ru, Pd or Pt compounds or complexes are used as catalysts, which can be modified with N- or P-containing ligands to influence the activity and / or selectivity. In the hydroformylation reaction of olefins with more than two carbon atoms, the formation of mixtures of isomeric aldehydes can occur due to the possible CO addition to each of the two carbon atoms of a double bond. In addition, the use of olefins with at least four carbon atoms can also result in double bond isomerization, ie. H. to shift internal double bonds to a terminal position and vice versa.

Because of the much greater technical importance of the α-aldehydes, the aim is to optimize the hydroformylation processes in order to achieve the highest possible conversions with the lowest possible tendency to form olefins with non-confessing double bonds. There is also a need for hydroformylation processes which, starting from internal linear olefins, lead in good yields to α-and especially n-aldehydes. Here, the catalyst used must allow both the establishment of an equilibrium between internal and terminal double bond isomers and, as selectively as possible, the hydroformylation of the terminal olefins.

For example, for the production of ester plasticizers with good performance properties, there is a need for plasticizer alcohols with about 6 to 12 carbon atoms, which are branched to a small extent (so-called semi-linear alcohols) and for corresponding mixtures thereof. These include, in particular, 2-propylheptanol and alcohol mixtures containing it. For their preparation, for example, C-hydrocarbon mixtures, the butenes or butenes and Bu- Contain tane, hydroformylation and subsequent aldol condensation. When using hydroformylation catalysts with insufficient n-selectivity, hydroformylation can easily lead not only to the formation of n-valeraldehyde but also to undesired product aldehydes, which means that the entire process is economically disadvantageous.

It is known to use phosphorus-containing ligands for the stabilization and / or activation of the catalyst metal in the rhodium low-pressure hydroformylation. Suitable phosphorus-containing ligands are e.g. B. phosphines, phosphinites, phosphonites, phosphites, phosphoramidites, phospholes and phosphabenzenes. The currently most widely used ligands are triarylphosphines, such as. B. triphenylphosphine and sulfonated triphenylphosphine, since these have sufficient activity and stability under the reaction conditions. However, a disadvantage of these ligands is that generally only very large excesses of ligands yield satisfactory yields, in particular of linear aldehydes, and that internal olefins are practically not converted.

If the hydroformylation is carried out as a one-stage process, complete or almost complete conversions of the olefins used can often not be achieved for technical or process-economic reasons. This applies in particular to the use of olefin mixtures which contain olefins of different reactivity, for example olefins with internal double bonds and olefins with terminal double bonds. It is known to use two or more reaction stages for the hydroformylation in which the reactors are present, for example, in the form of a cascade in which the individual reactors are operated under different reaction conditions in order to achieve a higher conversion in a given reaction space than in a single reactor of the same volume achieve. For example, DE-A-100 35 120 and DE-A-100 35 370 describe processes for the hydroformylation of olefins in a two-stage reaction system.

EP-A-0 188 246 describes a two-stage hydroformylation process in which the gaseous discharge from the first hydroformylation stage, which contains unreacted olefins, product aldehydes and by-product saturated hydrocarbons, is fed into the second hydroformylation stage without separation. The catalyst compositions can differ in the first and second hydroformylation stages.

EP-A-0 423 769 describes a two-stage hydroformylation process, the reactors used in the first and in the second stage differing in terms of their mixing characteristics. The discharge from the first reactor system is subjected to a separation to obtain a stream which contains the unreacted olefins and which is fed into the second reactor system. The same catalyst system is used in both reaction stages, the only difference being the amount used. EP-A-0 213 639 describes bridged bisphosphite compounds with a diorganophosphite functionality and a triorganophosphite functionality and their use as ligands in rhodium-catalyzed hydroformylation. In general, and without the support of an exemplary embodiment, reference is made to the possible use of these catalyst systems in a two-stage hydroformylation process in which, for example, α-olefins are reacted in a first reactor and internal olefins in a second reactor.

EP-A-0 562 451 describes the preparation of mixtures of isomeric decyl alcohols by two-stage hydroformylation of an olefin mixture containing butene-1 and butene-2, aldol condensation of the aldehyde mixture obtained and subsequent hydrogenation. The hydroformylation takes place in the first stage in the presence of a homogeneous two-phase reaction system using rhodium complexes based on water-soluble phosphines and in the second stage in a homogeneous phase. How the reaction discharge from the first stage is taken and fed to the second stage is not disclosed; Exemplary embodiments are missing.

EP-A-0 646 563 has a disclosure content comparable to EP-A-0 562 451, the reaction in the second stage taking place in a homogeneous phase in the presence of cobalt compounds as catalysts.

DE-A-195 30 698 describes a process for working up an essentially liquid hydroformylation discharge, in which the pressure is first let down in a flash vessel, a liquid phase containing the catalyst, the high boilers and residual amounts of hydroformylation product and unreacted olefin and a gas phase essentially comprising the hydroformylation product, unreacted olefin, saturated hydrocarbons and unreacted synthesis gas is formed, the liquid phase is passed to the top and the gas phase to the bottom of a column and the phases are carried in countercurrent, at the top of the column one with olefin and withdrawing the enriched gaseous stream from the hydroformylation product and working it up further, and withdrawing a liquid stream at the bottom of the column and returning it to the hydroformylation.

WO 02/068370 describes a two-stage hydroformylation process, the first stage being carried out homogeneously, in two phases in the presence of water using water-soluble rhodium complex catalysts and the olefins which have not been converted in the first stage being reacted in a second stage in the presence of a homogeneous reaction system which is used as a Ligands include chelate diphosphines with a xanthene backbone. In this process, an exhaust gas stream is withdrawn from the first reaction stage, which essentially consists of unreacted olefinic compounds, carbon monoxide, carbon dioxide, hydrogen and the hydrogenation products of the olefin and is fed into the second reaction stage in gaseous form without further workup. WO 02/068371 has a disclosure content comparable to WO 02/068370, the reaction in the first reaction stage taking place in a homogeneous single-phase reaction system.

The process disclosed in the last two documents can only be implemented on a large industrial scale due to the gas feed from the first to the second reaction stage and the associated need for the use of compressors and is therefore economically disadvantageous.

The object of the present invention is to provide a process for the preparation of hydroformylation products of olefins which enables the simple and economical hydroformylation of olefin mixtures which contain olefins of different reactivity. The process is intended in particular for the hydroformylation of industrial mixtures of olefins with a terminal and internal double bond, for. B. 1-butene / 2-butene mixtures, to aldehyde products with high linearity with good sales. Another object of the invention is to provide a process for the preparation of 2-propylheptanol.

Accordingly, a process for the preparation of hydroformylation products of olefins has been found in which

a) an olefin-containing feed as well as carbon monoxide and hydrogen are fed into a first reaction zone and reacted in the presence of a first catalyst system,

b) a liquid stream consisting essentially of unreacted olefins and optionally saturated hydrocarbons is separated from the discharge from the first reaction zone,

c) the liquid stream obtained in step b) as well as carbon monoxide and hydrogen are fed into a second reaction zone and reacted in the presence of a second catalyst system.

Another object of the invention is a process for the preparation of 2-propylheptanol, which comprises the hydroformylation of butene by the aforementioned process, an aldol condensation of the hydroformylation products thus obtained and the subsequent hydrogenation of the condensation products.

The process according to the invention comprises, as stages, a first hydroformylation of olefins (e.g. an olefin-containing hydrocarbon feedstock) up to a partial conversion (stage a)), the separation of the reaction effluent from the first hydroformylation to obtain an essentially unreacted olefin, and if present, saturated hydrocarbons existing liquid stream (stage b)) and a subsequent second hydroformylation of the olefin-containing stream obtained (stage c)). An essential characteristic of the invention is that two different catalyst systems are used for the first and for the second hydroformylation. By suitable choice of the catalyst systems, the present process enables a large number of olefinically unsaturated compounds, in particular also mixtures of olefins with different reactivity towards hydroformylation, with high conversions and, if desired, also with a high n-selectivity to be hydroformylated.

Suitable olefin feedstocks for the process according to the invention are in principle all compounds which contain one or more ethylenically unsaturated double bonds. These include olefins with terminal and internal double bonds, straight-chain and branched olefins, cyclic olefins and olefins which have essentially inert substituents under the hydroformylation conditions. Preferred are olefin feedstocks which contain olefins having 4 to 12, particularly preferably 4 to 6, carbon atoms. The olefins used for the hydroformylation are preferably selected from linear (straight-chain) olefins and olefin mixtures which contain at least one linear olefin. With the process according to the invention, in particular linear α-olefins, linear internal olefins and mixtures of linear α-olefins and linear internal olefins can be hydroformylated.

Suitable substrates for the hydroformylation process according to the invention are preferably C ₄ -C ₂₀ - olefins, e.g. B. 1-butene, isobutene, 1-pentene, 2-methyl-1-butene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1 -decene, 1 -undecene, 1-dodecene, allyl alcohols, etc Linear α-olefins and olefin mixtures which contain at least one linear α-olefin are preferred.

The unsaturated compound used for the hydroformylation is preferably selected from internal linear olefins and olefin mixtures which contain at least one internal linear olefin. Suitable linear internal olefins are preferably C ₄ -C ₂₀ olefins, such as 2-butene, 2-pentene, 2-hexene, 3-hexene, 2-heptene, 3-heptene, 2-octene, 3-octene, 4-octene etc. and mixtures thereof.

Suitable branched internal olefins are preferably C ₄ -C ₂ o-olefins such as 2-methyl butene-2, 2-methyl-2-pentene, 3-methyl-2-pentene, branched, internal heptene mixtures, branched, internal octene mixtures, branched, internal non-mixtures, branched, internal decene mixtures, branched, internal undecene mixtures, branched, internal dodecene mixtures etc.

Suitable olefins to be hydroformylated are also C ₅ -C ₈ cycloalkenes, such as cyclopentene, cyclohexene, cycloheptene, cyclooctene and their derivatives, such as, for. B. whose C C- ₂₀ alkyl derivatives with 1 to 5 alkyl substituents. Suitable olefins to be hydroformylated Also fine are vinyl aromatics, such as styrene, α-methylstyrene, 4-isobutylstyrene etc. Suitable olefins to be hydroformylated are furthermore α, β-ethylenically unsaturated mono- and / or dicarboxylic acids, their esters, half-esters and amides, such as acrylic acid, methacrylic acid, Maleic acid, fumaric acid, crotonic acid, itaconic acid, methyl 3-pentenoate, methyl 4-pentenoate, methyl oleic acid, methyl acrylate and methyl methacrylate. Suitable olefins to be hydroformylated are furthermore unsaturated nitrites, such as 3-pentenenitrile, 4-pentenenitrile and acrylonitrile. Also suitable are vinyl ethers, such as vinyl methyl ether, vinyl ethyl ether, vinyl propyl ether, etc. Suitable olefins to be hydroformylated are furthermore alkenols, alkenediols and alkadienols, such as 2,7-octadienol-1. Suitable olefins to be hydroformylated are also di- or polyenes with isolated or conjugated double bonds. These include e.g. B. 1, 3-butadiene, 1, 4-pentadiene, 1, 5-hexadiene, 1, 6-heptadiene, 1, 7-octadiene, 1, 9-decadiene, vinylcyclohexene, dicyclopentadiene, 1, 5,9-cyclooctatriene, Butadiene homo- and copolymers and olefins with terminal and internal double bonds, such as 1,4-octadiene.

A technically available olefin-containing hydrocarbon mixture is preferably used in the hydroformylation process according to the invention.

Preferred olefin mixtures available on an industrial scale result from the hydrocarbon splitting in petroleum processing, for example by cat cracking, such as fluid catalytic cracking (FCC), thermal cracking or hydrocracking with subsequent dehydrogenation. A suitable technical olefin mixture is the C-cut. C ₄ cuts are available, for example, by fluid catalytic cracking or steam cracking of gas oil or by steam cracking from naphtha. Depending on the composition of the C _{4 cut, a} distinction is made between the total C _{4 cut} (raw C ₄ cut), the so-called raffinate I obtained after the separation of 1,3-butadiene and the raffinate II obtained after the isobutene separation. Another suitable technical olefin mixture is the C _{5 cut} available from naphtha cleavage. Olefin-containing hydrocarbon mixtures having 4 to 6 carbon atoms suitable for use in step a) can furthermore be obtained by catalytic dehydrogenation of suitable paraffin mixtures which are available on an industrial scale. For example, the production of C ₄ -olefin mixtures from liquid gases (liquefied petroleum gas, LPG) and liquefiable natural gases (liquified natural gas, LNG) is possible. In addition to the LPG fraction, the latter also comprise larger amounts of higher molecular weight hydrocarbons (light naphtha) and are therefore also suitable for the production of C ₅ and C ₆ olefin mixtures. The production of olefin-containing hydrocarbon mixtures which contain monoolefins having 4 to 6 carbon atoms from LPG or LNG streams is carried out by customary processes known to the person skilled in the art, which generally comprise one or more workup steps in addition to the dehydrogenation. This includes, for example, the separation of at least some of the saturated hydrocarbons contained in the aforementioned olefin feed mixtures. These can be used again, for example, for the production of olefin feedstocks by cracking and / or dehydrogenation. The in the invention However, olefins used in the process can also contain a proportion of saturated hydrocarbons which are inert towards the hydroformylation conditions according to the invention. The proportion of these saturated components is generally at most 60% by weight, preferably at most 40% by weight, particularly preferably at most 20% by weight, based on the total amount of the olefins and saturated hydrocarbons contained in the hydrocarbon feedstock.

A raffinate II suitable for use in the process according to the invention has, for example, the following composition:

0.5 to 5% by weight of isobutane, 5 to 20% by weight of n-butane, 20 to 40% by weight of trans-2-butene, 10 to 20% by weight of cis-2-butene, 25 to 55% by weight of 1-butene, 0.5 to 5% by weight of isobutene

as well as trace gases, such as 1,3-butadiene, propene, propane, cyclopropane, propadiene, methylcyclopropane, vinyl acetylene, pentenes, pentanes, etc., each in the range of at most 1% by weight.

The reaction system used according to the invention has two reaction zones, each of which can comprise one or more, the same or different reactors. In the simplest case, a reaction zone is formed by a single reactor. Both the reactors of each individual zone and the reactors forming the different stages can each have the same or different mixing characteristics. The individual reactors of the two zones can, if desired, be divided up one or more times by internals. If two or more reactors form a zone (stage) of the reaction system, they can be interconnected as desired, e.g. B. in parallel or in series.

Suitable pressure-resistant reaction apparatus for hydroformylation are known to the person skilled in the art. These include the commonly used reactors for gas-liquid reactions, such as. B. tubular reactors, stirred tanks, gas circulation reactors, bubble columns, etc., which can optionally be divided by internals.

Carbon monoxide and hydrogen are usually used in the form of a mixture, the so-called synthesis gas. The composition of the synthesis gas used in the process according to the invention can vary within wide ranges. The same or different molar ratios of CO to H ₂ can be set in the two reaction zones forming the reaction system and, if appropriate, in the reactors forming a reaction zone. The molar ratio of carbon monoxide and hydrogen is generally 1: 1000 to 1000: 1, preferably 1: 100 to 100: 1. The temperature in the hydroformylation reaction in the two reaction zones is generally in a range from about 20 to 200 ° C., preferably about 50 to 190 ° C., in particular about 60 to 180 ° C. If desired, a higher temperature can be set in the second reaction zone than in the first reaction zone, e.g. B. to achieve the most complete possible conversion of more difficult hydroformylatable olefins. If a reaction zone comprises more than one reactor, these can also have the same or different temperatures. The reaction in the two reaction zones is preferably carried out at a pressure in a range from about 1 to 700 bar, particularly preferably 3 to 600 bar, in particular 5 to 50 bar. The reaction pressure can be varied in the zones used for the hydroformylation depending on the activity of the hydroformylation catalyst used. The hydroformylation catalysts described in more detail below allow, for. T. implementation in a range of low pressures, such as in the range of about 1 to 100 bar.

The reactor volume and / or the residence time of the first reaction zone are selected such that in general at least about 10% by weight of the olefin fed in, based on the total olefin content of the olefin-containing hydrocarbon mixture used for the hydroformylation, is reacted. The conversion in the first reaction zone based on the amount of olefin in the olefin-containing feed is preferably at least 20% by weight.

Suitable hydroformylation catalysts for the first and second hydroformylation stages are very generally the customary transition metal compounds and complexes known to the person skilled in the art, which can be used both with and without cocatalysts. The transition metal is preferably a metal from subgroup VIII of the periodic table and in particular Co, Ru, Rh, Pd, Pt, Os or Ir, especially Rh, Co, Ir or Ru.

In the following, the expression "alkyl" includes straight-chain and branched alkyl groups. These are preferably straight-chain or branched CrC ₂ o -alkyl, preferably dC ^ alkyl, particularly preferably CrC ₈ alkyl and very particularly preferably CrC ₄ alkyl groups. Examples of alkyl groups are in particular methyl, ethyl, propyl, isopropyl, n-butyl, 2-butyl, sec-butyl, tert-butyl, n-pentyl, 2-pentyl, 2-methylbutyl, 3-methylbutyl, 1, 2 -Dimethylpropyl, 1, 1 -Dimethylpropyl, 2,2-Dimethylpropyl, 1 -Ethylpropyl, n-Hexyl, 2-Hexyl, 2-Methylpentyl, 3-Methylpentyl, 4-Methylpentyl, 1, 2-Dimethylbutyl, 1, 3-Dimethylbutyl , 2,3-dimethylbutyl, 1, 1-dimethylbutyl, 2,2-dimethylbutyl, 3,3-dimethylbutyl, 1, 1, 2-trimethylpropyl, 1, 2,2-trimethylpropyl, 1-ethylbutyl, 2-ethylbutyl, 1 -Ethyl- 2-methylpropyl, n-heptyl, 2-heptyl, 3-heptyl, 2-ethylpentyl, 1-propylbutyl, n-octyl, 2-ethylhexyl, 2-propylheptyl, nonyl, decyl. The term "alkyl" also includes substituted alkyl groups which generally have 1, 2, 3, 4 or 5, preferably 1, 2 or 3 and particularly preferably 1, substituents selected from the groups cycloalkyl, aryl, hetaryl, halogen, NE ¹ E ² , NE ¹ E ² E ³⁺ , COOH, carboxylate, -SO ₃ H and sulfonate.

The term "alkylene" for the purposes of the present invention stands for straight-chain or branched alkanediyl groups having 1 to 4 carbon atoms.

For the purposes of the present invention, the term “cycloalkyl” includes unsubstituted and substituted cycloalkyl groups, preferably C ₅ -C ₇ cycloalkyl groups, such as cyclopentyl, cyclohexyl or cycloheptyl, which, in the case of a substitution, are generally 1, 2, 3, 4 or 5 , preferably 1, 2 or 3 and particularly preferably 1 substituents selected from the groups alkyl, alkoxy and halogen.

The term "heterocycloalkyl" in the context of the present invention encompasses saturated, cycloaliphatic groups with generally 4 to 7, preferably 5 or 6 ring atoms, in which 1 or 2 of the ring carbon atoms are replaced by heteroatoms selected from the elements oxygen, nitrogen and sulfur and which may optionally be substituted, where in the case of a substitution, these heterocycloaliphatic groups 1, 2 or 3, preferably 1 or 2, particularly preferably 1, selected from alkyl, aryl, COOR ^f , COO ^" M ⁺ and NE ¹ E ² Examples of such heterocycloaliphatic groups are pyrrolidinyl, piperidinyl, 2,2,6,6-tetramethylpiperidinyl, imidazolidinyl, pyrazolidinyl, oxazolidinyl, morpholidinyl, thiazolidinyl, isothiazolidinyl, isoxazolidinyl, piperazinyl-, tetrahydethrropyryl, urethane, tetrahydrothyryl, urethane Called dioxanyl.

For the purposes of the present invention, the term “aryl” encompasses unsubstituted and substituted aryl groups, and preferably stands for phenyl, tolyl, xylyl, mesityl, naphthyl, fluorenyl, anthracenyl, phenanthrenyl or naphthacenyl, particularly preferably for phenyl or naphthyl, where these Aryl groups in the case of substitution in general 1, 2, 3, 4 or 5, preferably 1, 2 or 3 and particularly preferably 1 substituent, selected from the groups alkyl, alkoxy, carboxyl, carboxylate, trifluoromethyl, -SO ₃ H, sulfonate, NE ¹ E ² , alkylene-NE ¹ E ² , nitro, cyano or halogen.

For the purposes of the present invention, the term “hetaryl” encompasses unsubstituted or substituted heterocycloaromatic groups, preferably the groups pyridyl, quinolinyl, acridinyl, pyridazinyl, pyrimidinyl, pyrazinyl, and also the subgroup of the “pyrrole group”, these heterocycloaromatic groups in the case of a Substitution in general 1, 2 or 3 substituents selected from the groups alkyl, alkoxy, carboxyl, carboxylate, -SO ₃ H, sulfonate, NE ¹ E ² , alkylene-NE ¹ E ² , trifluoromethyl or halogen can carry. For the purposes of the present invention, the term “pyrrole group” stands for a number of unsubstituted or substituted, heterocycloaromatic groups which are structurally derived from the pyrrole backbone and contain a pyrrolic nitrogen atom in the heterocycle which covalently links to other atoms, for example a pnicogen atom can be. The term "pyrrole group" thus includes the unsubstituted or substituted groups pyrrolyl, imidazolyl, pyrazolyl, indolyl, purinyl, indazolyl, benzotriazolyl, 1, 2,3-triazolyl, 1, 3,4-triazolyl and carbazolyl, which in the case of a Substitution in general 1, 2 or 3, preferably 1 or 2, particularly preferably 1 substituent, selected from the groups alkyl, alkoxy, acyl, carboxyl, carboxylate, -SO ₃ H, sulfonate, NE ¹ E ² , alkylene-NE ¹ E ² , trifluoromethyl or halogen. A preferred substituted indolyl group is the 3-methyl-indolyl group.

Accordingly, the term "bispyrrole group" for the purposes of the present invention includes divalent groups of the formula

Py-I-Py,

which contain two pyrrole groups linked by direct chemical bonding or alkylene, oxa, thio, imino, silyl or alkylimino groups, such as the bisindoldiyl group of the formula

as an example of a bispyrrole group which contains two directly linked pyrrole groups, in this case indolyl, or the bispyrroldiylmethane group of the formula

as an example of a bispyrrole group which contains two pyrrole groups linked via a methylene group, in this case pyrrolyl. Like the pyrrole groups, the bispyrrole groups can also be unsubstituted or substituted and, in the case of substitution per pyrrole group unit, generally 1, 2 or 3, preferably 1 or 2, in particular 1, substituents selected from alkyl, alkoxy, carboxyl, carboxylate, -SO ₃ H, Sulfonate, NE ¹ E ² , alkylene-NE ¹ E ² , trifluoromethyl or halogen, with these details of the number of possible substituents linking the pyrrole groups units by direct chemical bonding or by the linkage mediated by means of the abovementioned groups is not regarded as a substitution.

In the context of this invention, carboxylate and sulfonate preferably represent a derivative of a carboxylic acid function or a sulfonic acid function, in particular a metal carboxylate or sulfonate, a carboxylic acid or sulfonic acid ester function or a carboxylic acid or sulfonic acid amide function. These include e.g. B. the esters with CC ₄ alkanols, such as methanol, ethanol, n-propanol, isopropanol, n-butanol, sec-butanol and tert-butanol. These also include the primary amides and their N-alkyl and N, N-dialkyl derivatives.

The above explanations of the terms "alkyl", "cycloalkyl", "aryl", "heterocycloalkyl" and "hetaryl" apply accordingly to the terms "alkoxy", "cycloalkoxy", "aryloxy", "heterocycloalkoxy" and "hetaryloxy" ".

For the purposes of the present invention, the term “acyl” stands for alkanoyl or aroyl groups with generally 2 to 11, preferably 2 to 8, carbon atoms, for example for the acetyl, propanoyl, butanoyl, pentanoyl, hexanoyl, hepta- noyl, 2-ethylhexanoyl, 2-propylheptanoyl, benzoyl or naphthoyl group.

The groups NE E ² , NE ⁴ E ⁵ , NE ⁷ E ⁸ , NE ¹⁰ E ¹¹ , NE ¹³ E ¹⁴ , NE ¹⁶ E ¹⁷ NE ¹⁹ E ²⁰ , NE ²² E ²³ and NE ²⁵ E ²⁶ preferably stand for N, N -Dimethylamino, N, N-diethylamino, N, N-dipropylamino, N, N-diisopropylamino, NN-di-n-butylamino, N, N-di-t.-butylamino, N, N-dicyclohexylamino or N, N- diphenylamino.

Halogen represents fluorine, chlorine, bromine and iodine, preferably fluorine, chlorine and bromine.

M ⁺ stands for a cation equivalent, ie for a monovalent cation or the portion of a multivalent cation corresponding to a positive single charge. The cation M ⁺ serves only as a counterion for the neutralization of negatively charged substituent groups, such as the COO or the sulfonate group, and can in principle be chosen as desired. Alkali metal ions, in particular Na ⁺ , K ⁺ , Li ⁺ ions or onium ions, such as ammonium, mono-, di-, tri-, tetraalkylammonium, phosphonium, tetraalkylphosphonium or tetraarylphosphonium ions, are therefore preferred used.

The same applies to the anion equivalent X ^' , which only serves as a counterion of positively charged substituent groups, such as the ammonium groups, and can be chosen arbitrarily from monovalent anions and the proportions of a multivalent anion corresponding to a negative single charge. Suitable anions are, for example, halide ions X ^' , such as chloride and bromide. Preferred anions are sulfate and sulfonate, for example SO ^{2 '} , tosylate, trifluoromethanesulfonate and methyl sulfonate.

The values for x stand for an integer from 1 to 240, preferably for an integer from 3 to 120. Condensed ring systems can be fused aromatic, hydroaromatic and cyclic compounds. Condensed ring systems consist of two, three or more than three rings. Depending on the type of linkage, a distinction is made between condensed ring systems between ortho-annulation, ie each ring has an edge or two atoms in common with each neighboring ring, and peri-annulation, in which one carbon atom belongs to more than two rings. Preferred among the condensed ring systems are orthocondensed ring systems.

Preferred complex compounds comprise at least one phosphorus atom-containing compound as ligand. The compounds containing phosphorus atoms are preferably selected from PF ₃ , phospholes, phosphabenzenes, monodentate, bidentate and polydentate phosphine, phosphinite, phosphonite, phosphoramidite, phosphite ligands and mixtures thereof.

The catalysts used according to the invention for the first and second hydroformylation stage can contain at least one further ligand, which is preferably selected from halides, amines, carboxylates, acetylacetonate, aryl or alkyl sulfonates, hydride, CO, olefins, dienes, cycloolefins, nitriles, N-containing Heterocycles, aromatics and heteroaromatics, ethers and mixtures thereof.

In general, catalytically active species of the general formula HχM _y (CO) _z Lq are formed from the catalysts or catalyst precursors used in each case under hydroformylation conditions, where M for a metal of subgroup VIII, L for a phosphorus-containing compound and q, x, y , z are integers, depending on the valency and type of the metal and the binding of the ligand L. Preferably, z and q are independently at least 1, such as. B. 1, 2 or 3. The sum of z and q is preferably from 1 to 5. The complexes can, if desired, additionally have at least one of the further ligands described above.

According to a preferred embodiment, the hydroformylation catalysts are prepared in situ in the reactor used for the hydroformylation reaction. If desired, however, the catalysts of the invention can also be prepared separately and isolated by customary processes. For the in-situ preparation of the catalysts of the invention, one can e.g. B. at least one phosphorus atom-containing ligand, a compound or a complex of a metal from subgroup VIII, optionally at least one further additional ligand and, if appropriate, an activating agent in an inert solvent under the hydroformylation conditions.

Suitable rhodium compounds or complexes are e.g. B. rhodium (II) - and rhodium (III) salts, such as rhodium (III) chloride, rhodium (III) nitrate, rhodium (III) sulfate, potassium - Rhodium sulfate, rhodium (II) or rhodium (III) carboxylate, rhodium (II) and rhodium (III) acetate, rhodium (III) oxide, salts of rhodium (III) acid, trisammonium hexachlororhodate (III) etc. Also suitable are rhodium complexes such as rhodium biscarbonylacetylacetonate, acetylacetonatobisethylene rhodium (III) etc. Rhodium biscarbonylacetylacetonate or rhodium acetate are preferably used.

Ruthenium salts or compounds are also suitable. Suitable ruthenium salts are, for example, ruthenium (III) chloride, ruthenium (IV), ruthenium (VI) or ruthenium (VIII) oxide, alkali metal salts of ruthenium oxygen acids such as K ₂ RuO ₄ or KRuO ₄ or complex compounds, such as, for. B. RuHCI (CO) (PPh ₃ ) ₃ . The metal carbonyls of ruthenium such as trisruthenium dodecacarbonyl or hexaruthenium octadecacarbonyl, or mixed forms in which CO is partly replaced by ligands of the formula PR ₃ , such as Ru (CO) ₃ (PPh ₃ ) ₂ , can also be used in the process according to the invention.

Suitable cobalt compounds are, for example, cobalt (II) chloride, cobalt (II) sulfate, cobalt (II) carbonate, cobalt (II) nitrate, their amine or hydrate complexes, cobalt carboxylates, such as cobalt acetate, cobalt ethyl hexanoate, cobalt naphthanoate, and cobalt caproate -Complex. Here too, the carbonyl complexes of cobalt such as dicobaltoctacarbonyl, tetracobaltdodecacarbonyl and hexacobalthexadecacarbonyl can be used.

The above-mentioned and other suitable compounds of cobalt, rhodium, ruthenium and iridium are known in principle and are adequately described in the literature, or they can be prepared by the skilled worker analogously to the already known compounds.

Suitable activating agents are e.g. B. Bronsted acids, Lewis acids, such as BF ₃ , AICI ₃ , ZnCI ₂ , SnCI ₂ and Lewis bases.

The solvents used are preferably the aldehydes which are formed in the hydroformylation of the respective olefins, and their higher-boiling secondary reaction products, for. B. the products of aldol condensation. Likewise suitable solvents are aromatics, such as toluene and xylenes, hydrocarbons or mixtures of hydrocarbons, also for diluting the above-mentioned aldehydes and the secondary products of the aldehydes. Other solvents are esters of aliphatic carboxylic acids with alkanols, for example ethyl acetate or Texanol ™, ethers such as tert-butyl methyl ether and tetrahydrofuran.

Suitable hydroformylation catalysts for the first and second hydroformylation stages are, for. B. in Beller et al., Journal of Molecular Catalysis A, 104 (1995), pp. 17-85, which is incorporated herein by reference in its entirety. The specific selection of the first and second catalyst systems is based on the olefin-containing hydrocarbon feedstock. The first catalyst system is selected so that the partial conversion aimed for in the first stage is achieved with the desired product selectivity. In a preferred embodiment, a targeted conversion of olefins with terminal double bonds with high n-selectivity is aimed for in the first hydroformylation. The second hydroformylation stage is preferably used to complete the conversion of terminal olefins and / or for the targeted implementation of olefins with internal double bonds, likewise with high n-selectivity.

The first catalyst system preferably comprises at least one complex of a metal of subgroup VIII of the Periodic Table of the Elements with at least one organic phosphorus (III) compound as ligand.

The organic phosphorus (III) compound is preferably selected from compounds of the general formula PR ¹ R ² R ³ , in which R, R ² and R ³ independently of one another are alkyl, cycloalkyl, heterocycloalkyl, aryl or hetaryl, the alkyl radicals 1, 2, 3, 4 or 5 substituents selected from cycloalkyl, heterocycloalkyl, aryl, hetaryl, alkoxy, cycloalkoxy, heterocycloalkoxy, aryloxy, hetaryloxy, COOH, carboxylate, SO ₃ H, sulfonate, NE ¹ E ² , NE E ² E ³⁺ X ^{"can have} halogen, nitro, acyl or cyano, in which E ¹ , E ² and E ³ each represent the same or different radicals selected from hydrogen, alkyl, cycloalkyl, or aryl and X ^{" represents} an anion equivalent, and wherein the Cycloalkyl, heterocycloalkyl, aryl and hetaryl radicals can have 1, 2, 3, 4 or 5 substituents which are selected from alkyl and the substituents mentioned above for the alkyl radicals R ¹ , R ² and R ³ , where R ¹ and R ² together with the phosphorus atom to which they gave and are also a 5- to 8-membered heterocycle, which is optionally additionally fused one, two or three times with cycloalkyl, heterocycloalkyl, aryl or hetaryl, the heterocycle and, if present, the fused groups independently of one another can each carry one, two, three or four substituents which are selected from alkyl and the substituents mentioned above for the alkyl radicals R ¹ , R ² and R ³ .

Suitable organic phosphorus (III) compounds are furthermore chelate compounds of the general formula R ¹ R ² PY ¹ -PR ¹ R ² , in which R ¹ and R ^{2 have} the meanings indicated above and Y ^{1 represents} a divalent bridging group. The two radicals R ¹ , the two radicals R ² and the two radicals R ^{3 can} each have the same or different meanings.

The bridging group Y ¹ is preferably selected from the groups of the formulas III a to III.t described below, to which reference is made in full here. In a particularly preferred embodiment, Y ^{1 represents} a group of the formula IIIa. In a further particularly preferred embodiment, Y ^{1 represents} a radical of the formula

wherein

R ', R ", R ^IN , R ^IV , R ^V and R ^vι independently of one another for hydrogen, alkyl, cycloalkyl, heterocycloalkyl, aryl, hetaryl, hydroxy, thiol, polyalkylene oxide, polyalkyleneimine, alkoxy, halogen, COOH, carboxylate, SO ₃ H, sulfonate, NE ⁷ E ⁸ , alkylene-NE ⁷ E ⁸ , trifluoromethyl, nitro, alkoxycarbonyl, acyl or cyano, in which E ⁷ and E ⁸ each represent the same or different radicals selected from hydrogen, alkyl, cycloalkyl and aryl,

where two adjacent radicals R ¹ to R ^vι together with the carbon atoms of the benzene nucleus to which they are attached can also represent a condensed ring system with 1, 2 or 3 further rings, and

R ^d and R ^{e are} independently hydrogen, alkyl, cycloalkyl, heterocycloalkyl, aryl or hetaryl.

Particularly preferred hydroformylation catalysts for use in the first reaction zone are phosphorus-containing rhodium catalysts, as described, for. B. under the hydroformylation conditions in situ from a rhodium source and a tri-rylphosphine, eg. B. triphenylphosphine.

The catalysts based on at least one phosphinamidite ligand disclosed in WO 00/56451 are also suitable for use as the first catalyst system. The Veen et al. in Angew. Chem. Int. ed. 1999, 38, 336 described catalysts based on chelate diphosphines with backbones of the xanthene type. Also suitable are the metal complexes described in WO 01/85661 with adamantane ligands and the metal complexes described in WO 01/85662 based on diphosphine ligands with two bridged phosphaamantantyl residues or phospha-oxa-adamantyl residues. The hydroformylation catalysts described in DE-A-100 23 471 are also suitable. The hydroformylation catalysts based on phosphorus-containing, diaryl-fused bicyclo [2.2.n] basic bodies are preferably suitable as described in WO 01/58589.

The second catalyst system preferably comprises at least one complex of a metal of subgroup VIII of the Periodic Table of the Elements with at least one ner phosphorus chelate compound as a ligand. The phosphorus chelate compound is preferably selected from compounds of the general formula I ^α - (X ¹ ) -P- (X ³ ) rY ² - (X ⁴ ) gP- (X ⁶ ), - ^δ

wherein

Y ^{2 represents} a divalent bridging group,

R ^α , R ^ß , R ^γ and R ^δ independently of one another represent alkyl, cycloalkyl, heterocycloalkyl, aryl or hetaryl, the alkyl radicals 1, 2, 3, 4 or 5 substituents selected from cycloalkyl, heterocycloalkyl, aryl, hetaryl, alkoxy , Cycloalkoxy, heterocycloalkoxy, aryloxy, hetaryloxy, hydroxy, thiol, polyalkylene oxide, polyalkylenimine, COOH, carboxylate, SO ₃ H, sulfonate, NE ¹⁰ E ¹¹ , NE ¹⁰ E ¹ E ¹²⁺ χ-, halogen, nitro, May have acyl or cyano, in which E ¹⁰ , E ¹¹ and E ¹² each represent the same or different radicals selected from hydrogen, alkyl, cycloalkyl, or aryl and X ^"represents an anion equivalent, and wherein the cycloalkyl, heterocycloalkyl, aryl - and hetaryl radicals R ^α , R ^β , R ^γ and R ^{δ may have} 1, 2, 3, 4 or 5 substituents which are selected from alkyl and those previously given for the alkyl radicals R ^α , R ^β , R ^γ and R ^δ mentioned substituents, or

R ^α and R ^ß and / or R ^γ and R ^δ together with the phosphorus atom and, if present, the groups X ¹ , X ² , X ⁵ and X ⁶ to which they are attached for a 5- to 8-membered group Heterocycle, which is optionally fused one, two or three times with cycloalkyl, heterocycloalkyl, aryl or hetaryl, the heterocycle and, if present, the fused groups independently of one another can carry one, two, three or four substituents which are selected from alkyl, cycloalkyl, heterocycloalkyl, aryl, hetaryl, hydroxy, thiol, polyalkylene oxide, polyalkyleneimine, alkoxy, halogen, COOH, carboxylate, SO ₃ H, sulfonate, NE ¹³ E ¹⁴ , NE ¹³ E ¹ E ¹⁵⁺ X \ nitro , Alkoxycarbonyl, acyl or cyano, in which E ¹³ , E ¹⁴ and E ¹⁵ each represent identical or different radicals selected from hydrogen, alkyl, cycloalkyl and aryl and X ^"represents an anion equivalent,

X ¹ , X ² , X ³ , X ⁴ , X ⁵ and X ^{6 are} independently selected from O, S, SiR ^ε R ^ξ and NR ^η , where R ^ε , R ^ξ and R ^{η are} independently hydrogen, alkyl, Cycloalkyl, heterocycloalkyl, aryl or hetaryl, and d, e, f, g, h and i are independently 0 or 1.

The bridging group Y ² in the formula I is preferably selected from the groups of the formulas IIIa to III.t described below, to which reference is made in full here.

In particular, the phosphorus chelate compounds used as the second catalyst system are selected from chelate phosphonites, chelate phosphites and chelate phosphoramidites.

Suitable for use as a second catalyst system are the catalysts described in WO 02/22261, which comprise at least one complex of a metal from subgroup VIII with at least one ligand, which is selected from chelate phosphonites and chelate phosphites with a xanthene backbone. The pnicogen chelate complexes based on pnicogen chelate compounds described in WO 02/083695 are also suitable as ligands which have a basic structure of the xanthene or triptycene type. Also suitable are the catalysts described in WO 03/018192 with at least one pyrrole-phosphorus compound as ligand. The catalysts described in German patent application 102 43 138.8 are also suitable. Reference is made in full to the disclosure of the aforementioned documents.

The second catalyst system preferably comprises at least one complex of a metal of subgroup VIII of the Periodic Table of the Elements with at least one phosphorus chelate compound of the general formula II

as ligands, in which

R ⁴ , R ⁵ , R ⁶ and R ⁷ independently of one another represent heteroatom-containing groups which are bonded to the phosphorus atom via an oxygen atom or an optionally substituted nitrogen atom or R ⁴ together with R ⁵ and / or R ⁶ together with R ⁷ form a double-bonded heteroatom-containing group which are bonded to the phosphorus atom via two heteroatoms selected from oxygen and / or optionally substituted nitrogen,

a and b independently of one another denote the number 0 or 1, and Y ^{3 represents} a divalent bridging group with 2 to 20 bridging atoms between the flanking bonds, at least two bridging atoms being part of an alicyclic or aromatic group.

The individual phosphorus atoms of the phosphorus chelate compounds of the formula II are each connected via two covalent bonds to the substituents R ⁴ and R ⁵ or R ⁶ and R ⁷ -, the - substituents, -R -, .. R ⁶ - and R ⁷ in a first embodiment are hetero atom-containing groups which are bonded to the phosphorus atom via an oxygen atom or an optionally substituted nitrogen atom, R ⁴ and R ⁵ or R ⁶ and R ⁷ not being connected to one another. R ⁴ , R ⁵ , R ⁶ and R ⁷ then preferably represent pyrrole groups bonded to the phosphorus atom Pn via the pyrrolic nitrogen atom. The meaning of the term pyrrole group corresponds to the definition given above.

In a further embodiment, R ⁴ together with R ⁵ and / or R ⁶ together with R ^{7 form} a divalent heteroatom-containing group which are bonded to the phosphorus atom via two heteroatoms selected from oxygen and optionally substituted nitrogen. The substituent R ⁴ together with the substituent R ⁵ and / or the substituent R ⁶ together with the substituent R ⁷ can then advantageously form a bispyrrole group bonded to the phosphorus atom via the pyrrolic nitrogen atoms. Furthermore, the substituent R ⁴ together with the substituent R ⁵ and / or the substituent R ⁶ together with the substituent R ⁷ can advantageously form a bridging group bonded to the phosphorus atom via two oxygen atoms.

Preferred are phosphorus chelate compounds in which the radicals R ⁴ , R ⁵ , R ⁶ and R ⁷ are selected independently of one another from groups of the formulas IIa to II. K:

Alk • Alk ΛSk ^ - COOAlk \\ \\ //

[ll. a) (II. b)

AlkOOC

AlkOOC COOAlk II. c) (II. d)

(II. E) (II. F): n.g)

wherein

Alk is a dC ₄ alkyl group and

R °, R ^p , R ^q and R ^r independently of one another represent hydrogen, dC ₄ alkyl, C 1 -C ₄ alkoxy, acyl, halogen, trifluoromethyl, d-Oralkoxycarbonyl or carboxyl.

Some advantageous pyrrole groups are listed below for illustration purposes:

H ₃ C COOCH,

(II. Al) (II. A2) (ii. Bi)

(iι.b2; [II.cl)

COOCH, (II. C2) (II. Dl)

(II.d2) (II. El] (II. E2)

H ₃ C: n.f3:: n.gi) (ii. Hl)

c COOCH,

(ii.il) (II.kl) (II.k2)

The 3-methylindolyl group (skatolyl group) of the formula II.f1 is particularly advantageous. Hydroformylation catalysts based on ligands containing one or more 3-Methylindolyl group (s) bound to the phosphorus atom are characterized by a particularly high stability and thus a particularly long catalyst life.

In a further advantageous embodiment of the present invention, the substituent R ⁴ together with the substituent R ⁵ or the substituent R ⁶ together with the substituent R ⁷ can contain a double-bonded group of the formula Py-IW which contains the pyrrole nitrogen atom bonded to the phosphorus atom

form,

wherein

Py is a pyrrole group

I stands for a chemical bond or for O, S, SiR ^ε R ^ξ , NR ^η or optionally substituted d-Cio-alkylene, preferably CR ^λ R ^μ ,

W represents cycloalkyloxy or amino, aryloxy or amino, hetaryloxy or amino

and

R ^ε , R ^ξ , R ^η , R ^λ and R ^μ independently of one another represent hydrogen, alkyl, cycloalkyl, heterocycloalkyl, aryl or hetaryl,

the designations used here have the meaning explained at the beginning.

Preferred divalent groups of the formula

Py-I-W

are z. B.

Preferred are phosphorus chelate compounds in which the substituent R ⁴ together with the substituent R ⁵ or the substituent R ⁶ together with the substituent R ^{7 is} a bispyrrole group of the formula

forms in which stands for a chemical bond or for O, S, SiR ^ε R ^ξ , NR ^η or optionally substituted d-do-alkylene, preferably CR ^λ R ^μ , in which R ^ε , R ^ξ , R ^η , R ^λ and R ^μ independently of one another represent hydrogen, alkyl, cycloalkyl, heterocycloalkyl, aryl or hetaryl,

R ³⁵ , R ^{35 '} , R ³⁶ , R ^36' , R ³⁷ , R ^{37 '} , R ³⁸ and R ^38' independently of one another for hydrogen, alkyl, cycloalkyl, heterocycloalkyl, aryl, hetaryl, W ^' COOR ¹ , W ^' COO ^' M ⁺ , W ^' (SO ₃ ) R', W ^' (SO ₃ ) ^" M ⁺ , W ^' PO ₃ (R ^f ) (R ³ ), W ^' (PO ₃ ) ² - (M ⁺ ) ₂ , W ^' NE ¹⁶ E ¹⁷ , W ^' (NE ¹⁶ E ¹⁷ E ¹⁸ ) ⁺ X ^" , W ^' OR ^f , W ^' SR ^f , (CHR ⁹ CH ₂ O) _x R ^f , (CH ₂ NE ¹⁶ ) _x R ^f , (CH ₂ CH ₂ NE ¹⁶ ) _x R ^f , halogen, trifluoromethyl, nitro, acyl or cyano, in which

W ^"represents a single bond, a hetero atom, a hetero atom-containing group or a divalent bridging group with 1 to 20 bridge atoms,

R ^f , E ¹⁶ , E ⁷ , E ¹⁸ each represent the same or different radicals selected from hydrogen, alkyl, cycloalkyl or aryl,

R ^{9 represents} hydrogen, methyl or ethyl,

M ^{+ stands} for a cation equivalent,

X ^"stands for an anion equivalent and x stands for an integer from 1 to 240,

where two adjacent radicals R ³⁵ and R ³⁶ and / or R ^{35 '} and R ^36' together with the carbon atoms of the pyrrole ring to which they are attached can also represent a condensed ring system with 1, 2 or 3 further rings.

I is preferably a chemical bond or a C 1 -C 8 -alkylene group, particularly preferably a methylene group.

To illustrate, some advantageous "bispyrrolyl groups" are listed below:

Also preferred are phosphorus chelate compounds of the general formula II, in which R ⁴ and R ⁵ and / or R ⁶ and R ⁷ each together with the pnicogen atom to which they are attached, for a group of the general formula ILA

stand in what

k and I independently of one another represent 0 or 1,

Q together with the phosphorus atom and the oxygen atoms to which it is attached represents a 5- to 8-membered heterocycle which may be mono-, di- or triple with cycloalkyl, heterocycloalkyl, aryl and / or hetaryl is fused, the fused groups independently of one another two, three, or four substituents selected from alkyl, alkoxy, cycloalkyl, aryl, halogen, hydroxy, thiol, polyalkylene oxide, polyalkyleneimine, COOH, carboxylate, SO ₃ H, sulfonate, NE ⁴ E ⁵ , alkylene-NE E ⁵ , nitro and cyano, and / or Q may have one, two or three substituents which are selected from alkyl, alkoxy, optionally substituted cycloalkyl and optionally substituted aryl, and / or Q by 1, 2 or 3 optionally substituted heteroatoms can be interrupted.

Depending on whether the group of the general formula ILA is bonded to the group Y ³ via an oxygen atom (a or b = 1) or a covalent bond (a or b = 0), and whether k and I for 0 or 1 stand, the phosphorus Lat compounds of formula II thus at least one phosphine, phosphinite, phosphonite and / or phosphite residue. The groups of the formula ILA are preferably bonded to the group Y ³ via an oxygen atom and k and I are 1 (phosphite groups).

The radical Q preferably represents a C ₂ -C ₆ alkylene bridge which is fused once or twice with aryl and / or which may have a substituent which is selected from alkyl, optionally substituted cycloalkyl and optionally substituted aryl, and / or which can be interrupted by an optionally substituted heteroatom.

The fused aryls of the radicals Q are preferably benzene or naphthalene. Fused benzene rings are preferably unsubstituted or have 1, 2 or 3, in particular 1 or 2, substituents which are selected from alkyl, alkoxy, halogen, SO ₃ H, sulfonate, NE ⁴ E ⁵ , alkylene-NE ⁴ E ⁵ , Trifluoromethyl, nitro, carboxyl, alkoxycarbonyl, acyl and cyano. Fused naphthalenes are preferably unsubstituted or have 1, 2 or 3, in particular 1 or 2, of the substituents mentioned above for the fused benzene rings in the non-fused ring and / or in the fused ring. In the case of the substituents of the fused aryls, alkyl is preferably dC ₄ -alkyl and in particular methyl, isopropyl and tert-butyl. Alkoxy is preferably dC -alkoxy and especially methoxy. Alkoxycarbonyl is preferably dC ₄ -alkoxycarbonyl. Halogen is especially fluorine and chlorine.

If the C ₂ -C ₆ alkylene bridge of the radical Q is interrupted by 1, 2 or 3, optionally substituted heteroatoms, these are preferably selected from O, S or NR ^m , where R ^{m is} alkyl, cycloalkyl or aryl. The C ₂ -C ₆ alkylene bridge of the radical Q is preferably interrupted by an optionally substituted heteroatom.

If the C ₂ -C ₆ alkylene bridge of the radical Q is substituted, it preferably has 1, 2 or 3, in particular 1, substituent which is / are selected from alkyl, cycloalkyl and aryl, the aryl substituent being 1, 2 or can carry 3 of the substituents mentioned for aryl. The alkylene bridge Q preferably has a substituent which is selected from methyl, ethyl, isopropyl, phenyl, p- (dC-alkyl) phenyl, preferably p-methylphenyl, p- (C ₁ -C ₄ -alkoxy) phenyl, preferably p -Methoxyphenyl, p-halophenyl, preferably p-chlorophenyl and p-trifluoromethylphenyl.

The radical Q is preferably a C ₃ -C ₆ -alkylene bridge which is fused and / or substituted as described above and / or interrupted by optionally substituted heteroatoms. In particular, the radical Q represents a C ₃ -C ₆ -alkylene bridge which is fused once or twice with benzene and / or naphthalene, the phenyl or naphthyl groups bearing 1, 2 or 3, in particular 1 or 2, of the aforementioned substituents can. The radical Q (ie R ⁴ and R ⁵ or R ⁶ and R ⁷ together), together with the phosphorus atom and the oxygen atoms to which it is bonded, preferably represents a 5- to 8-membered heterocycle, where Q (R ⁴ and R ⁵ or R ⁶ and R ⁷ together) represents a radical which is selected from the radicals of the formulas 11.1 to II.5,

(11.1) (II.2) (II.3)

(II.4) (ii-s)

wherein

Z ^{1 represents} O, S or NR ^m , where R ^{m represents} alkyl, cycloalkyl or aryl,

or Z ^{1 represents} a CrC ₃ alkylene bridge which can have a double bond and / or at least one substituent selected from alkyl, cycloalkyl or aryl substituents, the alkyl, cycloalkyl or aryl substituents in turn having one, two or can carry three of the substituents mentioned at the beginning for these groups,

or Z ^{1 represents} a C ₂ -C ₃ alkylene bridge which is interrupted by O, S or NR ^m ,

R ²⁰ , R ²¹ , R ²² , R ²³ , R ²⁴ , R ²⁵ , R ²⁶ , R ²⁷ , R ²⁸ and R ²⁹ independently of one another for hydrogen, alkyl, cycloalkyl, aryl, alkoxy, halogen, SO ₃ H, sulfonate, NE ¹⁹ E ²⁰ , alkylene-NE ¹⁹ E ²⁰ , trifluoromethyl, nitro, alkoxycarbonyl, carboxyl or cyano, where E ¹⁹ and E ²⁰ independently of one another represent hydrogen, alkyl, cycloalkyl or aryl. Q is preferably a radical of the formula 11.1, where R ²⁰ , R ²¹ and R ^{22 are} hydrogen.

Q is preferably a radical of the formula II.2a

(Ll.2a)

wherein

R ²⁰ and R ^{24 represent} hydrogen, CC ₄ -alkyl, CC ₄ -alkoxy, SO ₃ H, sulfonate, NE ⁹ E ¹⁰ , alkylene-NE ⁹ E ¹⁰ , preferably hydrogen, CC ₄ -alkyl or dC ₄ -alkoxy , in particular methyl, methoxy, isopropyl or tert-butyl,

R ²¹ and R ^{23 represent} hydrogen, -CC ₄ alkyl, preferably methyl, isopropyl or tert-butyl, dC ₄ alkoxy, preferably methoxy, fluorine, chlorine or trifluoromethyl. R ²¹ can also stand for SO ₃ H, sulfonate, NE ⁹ E ¹⁰ or alkylene NE ⁹ E ¹⁰ .

Q is preferably a radical of the formula II.3a

(II.3a)

wherein

R ²⁰ , R ^Z1 , R ^di and R ** have the meanings given above for formula II.2a, R ^{n represents} hydrogen, dC ₄ -alkyl, preferably methyl or ethyl, phenyl, p- (CrC-alkoxy) phenyl, preferably p-methoxyphenyl, p-fluorophenyl, p-chlorophenyl or p- (trifluoromethyl) phenyl.

Q is preferably a radical of the formula 11.4, where R ²⁰ to R ^{29 are} hydrogen.

Q is preferably a radical of the formula 11.4, in which R ²⁰ , R ² , R ²² , R ²³ , R ²⁴ , R ²⁵ , R ²⁷ and R ^{29 are} hydrogen and the radicals R ²⁶ and R ²⁸ independently of one another are alkoxycarbonyl, preferably methoxy, ethoxy, n-propyloxy or isopropyloxycarbonyl. In particular, the radicals R ²⁶ and R ^{28 are} in the ortho position to the phosphorus atom or, if present (k and / or 1 = 1), the oxygen atom.

Q is preferably a radical of the formula II.5, in which R ²⁰ to R ^{29 are} hydrogen and Z ^{1 is} CR ⁿ R ⁿ , where R ⁿ and R ⁿ independently of one another are hydrogen, -CC alkyl, preferably methyl or ethyl, phenyl, p- (dC ₄ -alkoxy) phenyl, preferably p-methoxyphenyl, p-fluorophenyl, p-chlorophenyl or p- (trifluoromethyl) phenyl.

Q is preferably a radical of the formula II.5, in which R ²⁰ , R ²¹ , R ²² , R ²³ , R ²⁴ , R ²⁵ , R ²⁷ and R ^{29 are} hydrogen, Z ^{1 is} CR ⁿ R ^{n '} and the radicals R ²⁶ and R ²⁸ independently of one another are alkoxycarbonyl, preferably methoxy, ethoxy, n-propyloxy or isopropyloxycarbonyl. In particular, the radicals R ²⁶ and R ^{28 are} in the ortho position to the phosphorus atom or oxygen atom.

According to a preferred embodiment, the bridging group Y ^{3 is} selected from groups of the formulas IIIa to III.t.

(III.a) (III.b)

: nι.c) (in. d)

(III. E)

: ιn.f) [iii.g)

(III.h) (in. I) (in. K)

(III.1 ⁾ (III.) (III. N)

(III.o) (III.) (III.q)

(III. R) (III. S] (III. T)

wherein

R ', R ^1' , R ", R"^' , R ¹ ", R ¹ "^' , R ^ιv , R ^{ιv '} , R ^v , R ^vι , R ^v ", R ^vι ", R ^ιx , R ^x , R ^xι and R ^x "independently of one another for hydrogen, alkyl, cycloalkyl, heterocycloalkyl, aryl, hetaryl, hydroxy, thiol, polyalkylene oxide, polyalkyleneimine, alkoxy, halogen, SO ₃ H, sulfonate, NE ²² E ²³ , alkylene NE ²² E ²³ , Trifluoromethyl, nitro, alkoxycarbonyl, carboxyl, acyl or cyano, in which E ²² and E ²³ each represent the same or different radicals selected from hydrogen, alkyl, cycloalkyl and aryl,

Z represents O, S, NR ¹⁵ or SiR ¹⁵ R ¹⁶ , where R ¹⁵ and R ¹⁶ independently of one another represent hydrogen, alkyl, cycloalkyl, heterocycloalkyl, aryl or hetaryl, or Z represents a dC ₄ alkylene bridge which can have a double bond and / or an alkyl, cycloalkyl, heterocycloalkyl, aryl or hetaryl substituent, or Z represents a C ₂ -C alkylene bridge which is interrupted by O, S or NR ¹⁵ or SiR ¹⁵ R ¹⁶ ,

where in the groups of the formula IIIa two adjacent radicals R ¹ to R ^vι together with the carbon atoms of the benzene nucleus to which they are bonded can also represent a condensed ring system with 1, 2 or 3 further rings,

where in the groups of formulas III. g to III. m two geminal residues R ¹ , R ^{1 '} ; R ", R ^{11 '} ; R"', R ^ιn and / or R ^ιv , R ^{ιv 'can} also represent oxo or a ketal thereof,

A ¹ and A ² independently of one another represent O, S, SiR ^a R ^b , NR ^C or CR ^d R ^e , where

R ^a , R ° and R ^c independently of one another represent hydrogen, alkyl, cycloalkyl, heterocycloalkyl, aryl or hetaryl,

R ^d and R ^e independently of one another represent hydrogen, alkyl, cycloalkyl, heterocycloalkyl, aryl or hetaryl or the group R ^d together with another group R ^d or the group R ^e together with another group R ^{e is} an intramolecular bridge group D form,

D for a double-bonded bridge group of the general formula

\ / \ / CC / \ is in the

R ⁹ , R ^{9 '} , R ¹⁰ and R ^10' independently of one another represent hydrogen, alkyl, cycloalkyl, aryl, halogen, trifluoromethyl, carboxyl, carboxylate or cyano, where R ^{9 '} together with R ^{10' also represent} the bond portion of a double bond between the two carbon atoms to which R ^{9 '} and R ^{10' are} bonded, and / or R ⁹ and R ¹⁰ together with the carbon atoms to which they are bonded also represent a 4- to 8-membered carbo- or heterocycle, which is optionally additionally fused one, two or three times with cycloalkyl, heterocycloalkyl, aryl or hetaryl, where the heterocycle and, if present, the fused groups can independently carry one, two, three or four substituents , which are selected from alkyl, cycloalkyl, heterocycloalkyl, aryl, hetaryl, COOR ^f , COO ^" M ⁺ , SO ₃ R ^f , SO ^" ₃ M ⁺ , NE ²⁵ E ²⁶ , alkylene-NE ²⁵ E ²⁶ , NE ²⁵ E ²⁶ E ²⁷⁺ χ-, alkylene-NE ²⁵ E ²⁶ E ²⁷⁺ χ-, OR ^f , SR ^f , (CHR ⁹ CH ₂ O) _y R ^f , (CH ₂ N (E ²⁵ )) _y R ^f , (CH ₂ CH ₂ N (E ²⁵ )) _y R ^f , halogen, trifluoromethyl, nitro, acyl or cyano , in which

R ^f , E ²⁵ , E ²⁶ and E ²⁷ each represent the same or different radicals selected from hydrogen, alkyl, cycloalkyl or aryl,

R ^{9 represents} hydrogen, methyl or ethyl,

M ^{+ stands} for a cation,

X ^"stands for an anion and y stands for an integer from 1 to 120, and

c is O or 1.

In the event that c = 0, the groups A ¹ and A ^{2 are} not connected to one another by a single bond.

The bridge group Y ³ preferably represents a group of the formula IIIa. In group IIIa, groups A ¹ and A ^{2 can} in general independently of one another represent O, S, SiR ^a R, NR ^C or CR ^d R ^e , the substituents R ^a , R and R ^c generally being independent of one another can be hydrogen, alkyl, cycloalkyl, heterocycloalkyl, aryl or hetaryl, whereas the groups R ^d and R ^e independently of one another represent hydrogen, alkyl, cycloalkyl, heterocycloalkyl, aryl or hetaryl or the group R ^d together with a further group R ^d or the group R ^e together with another group R ^e can form an intramolecular bridge group D.

D is preferably a double-bonded bridging group which is selected from the groups

in which R ⁹ , R ^{9 '} , R ¹⁰ and R ^10' independently of one another represent hydrogen, alkyl, cycloalkyl, aryl, halogen, trifluoromethyl, carboxyl, carboxylate or cyano or are linked together to form a C ₃ -C ₄ alkylene group and R ¹ , R ¹² , R ¹³ and R ¹⁴ independently of one another for hydrogen, alkyl, cycloalkyl, aryl, halogen, trifluoromethyl, COOH, carboxylate, cyano, alkoxy, SO ₃ H, sulfonate, NE ¹ E ² , alkylene-NE ¹ E ² E ³⁺ X ^" , aryl or nitro. The groups R ⁹ , R ^{9 '} , R ¹⁰ and R ^10' are preferably hydrogen, dC ₁₀ alkyl or carboxylate and the groups R ¹¹ , R ¹² , R ¹³ and R ^{14 are} hydrogen, d-Cio-alkyl, halogen , in particular fluorine, chlorine or bromine, trifluoromethyl, dC -alkoxy, carboxylate, sulfonate or aryl. R ⁹ , R ^{9 '} , R ¹⁰ , R ^10' , R ¹¹ , R ¹² , R ¹³ and R ¹⁴ are particularly preferably hydrogen. For use in an aqueous reaction medium, pnicogen chelate compounds are preferred in which 1, 2 or 3, preferably 1 or 2, in particular 1 of the groups R ¹¹ , R ¹² , R ¹³ and / or R ¹⁴ for a COO ^" M \ an SO ₃ ^" M ⁺ or a (NE ¹ E ² E ³ ) ⁺ X ^' group, where M ⁺ and X ^{" have} the meaning given above.

Particularly preferred bridge groups D are the ethylene group

and the 1, 2-phenylene group

If R ^d forms an intramolecular bridge group D with a further group R ^d or R ^e with a further group R ^e , ie the index c in this case is 1, it is inevitable that both A ¹ and A ² together form a bridging group, preferably, a CR ^d R ^e group, and are the bridging group Y ³ of the formula lll.a in this case preferably a triptycene like or ethanoanthracene-like carbon skeleton has.

Preferred bridging groups Y ³ of the formula lll.a except those ARTIGEM with triptycene carbon skeleton, those in which the subscript c is 0 and the groups A ¹ and A ² are selected from the groups O, S, and CR ^d R ^e, in particular under O, S, the methylene group (R ^d = R ^e = H), the dimethylmethylene group (R ^d = R ^e = CH ₃ ), the diethylene group (R ^d = R ^c = C ₂ H ₅ ), the di-n- propyl-methylene group (R ^d = R ^θ = n-propyl) or the di-n-butylmethylene group (R ^d = R ^e = n-butyl). In particular, those bridging groups Y are preferred in which A ¹ is different from A ² , where A ^{1 is} preferably a CR R ^e group and A ^{2 is} preferably an O or S group, particularly preferably an oxa group O. Particularly preferred bridging groups Y ³ of the formula lll.a are thus those which, ethanoanthracene-like or xanthene type (A ^1: CR ^d R ^e, A ² O) from a triptycene like framework are constructed.

In the bridge groups Y ^{3 of} the formula IIIa, the substituents R ¹ , R ¹¹ , R ¹ ", R ^ιv , R ^V and R ^{vι are} preferably selected from hydrogen, alkyl, alkoxy, cycloalkyl, heterocycloalkyl, aryl and hetaryl. According to one In the first preferred embodiment, R ¹ , R ", R ¹ ", R ^ιv , R ^v and R ^{vι are} hydrogen. According to a further preferred embodiment, R ¹ and R ^{vι are} independently of one another dC ₄ alkyl or dC alkoxy. Preferred are R ¹ and R ^vι selected from methyl, ethyl, isopropyl, tert-butyl and methoxy. R ", R ¹ ", R ^ιv and R preferably represent hydrogen in these compounds. According to a further preferred embodiment, R "and R ^v independently of one another for CC alkyl or dC ₄ alkoxy. R "and R ^v are preferably selected from methyl, ethyl, isopropyl and tert-butyl. In these compounds, R ¹ , R ¹ ", R ^ιv and R ^{vι preferably represent} hydrogen.

If in the bridge groups Y ^{3 of} the formula III a two adjacent radicals selected from R ¹ , R ", R ¹ ", R ^ι , R ^v and R ^l stand for a fused, ie fused, ring system, it is preferred around benzene or naphthalene rings. Fused benzene rings are preferably unsubstituted or have 1, 2 or 3, in particular 1 or 2, substituents which are selected from alkyl, alkoxy, halogen, SO ₃ H, sulfonate, NE ¹ E ² , alkylene-NE ¹ E ² , Trifluoromethyl, nitro, COOR ^f , alkoxycarbonyl, acyl and cyano. Fused naphthalene rings are preferably unsubstituted or have a total of 1, 2 or 3, in particular 1 or 2, of the substituents mentioned above for the fused benzene rings in the non-fused ring and / or in the fused ring.

Y ³ preferably represents a group of the formula III. b, wherein R ^ιv and R ^{v are} independently dC ₄ alkyl or C _r C ₄ alkoxy. R ^ιv and R are preferably selected from methyl, ethyl, isopropyl, tert-butyl and methoxy. In these compounds, R ', R ", R ^HI , R ^vι , R ^v " and R ^vι "are ^preferably hydrogen.

Furthermore, Y ³ preferably represents a group of the formula III.b, in which R ¹ and R ^{v 1} "independently of one another represent dC ₄ alkyl or dC ₄ alkoxy. R ¹ and R ^{v 1} " are particularly preferably tert-butyl , In these compounds R ", R ¹ ", R ^ιv , R ^v , R ^vι , R "are particularly preferably hydrogen. Furthermore, in these compounds R ¹ " and R ^ι independently of one another are C 1 -C ₄ -alkyl or CC ₄ alkoxy. R ¹ "and R ^ι are particularly preferably selected independently of one another from methyl, ethyl, isopropyl, tert-butyl and methoxy.

Y ³ further preferably represents a group of the formula III.b, in which R "and R ^v " represent hydrogen. In these compounds, R ¹ , R ¹ ", R ^ιv , R, R ^vι and R ^vι " are ^preferably independently of one another dC ₄ -alkyl or dC ₄ -alkoxy. R ¹ , R ¹ ", R ^ιv , R ^v , R ^vι and R ^vι " are particularly preferably selected independently of one another from methyl, ethyl, isopropyl, tert-butyl and methoxy. Y ³ furthermore preferably stands for a group of the formula III.c, in which Z stands for a dC-alkylene group, in particular methylene. In these compounds R ^ιv and R ^v are preferably independently of one another dC ₄ -alkyl or dC -alkoxy. R ^ιv and R ^v are particularly preferably selected independently of one another from methyl, ethyl, isopropyl, tert-butyl and methoxy. The radicals R ¹ , R ", R ¹ ", R ^vι , R ^v "and R ^vι " preferably represent hydrogen.

Furthermore, Y ³ preferably represents a group of the formula III.c, in which Z represents a CC ₄ alkylene bridge which has at least one alkyl, cycloalkyl or aryl radical. Z particularly preferably represents a methylene bridge which has two dC ₄ -alkyl radicals, in particular two methyl radicals. In these compounds, the radicals R ¹ and R ^{v 1 are preferably} independently of one another CC ₄ -alkyl or C 1 -C ₄ alkoxy. Particularly preferably R ¹ and R ^{v are} independently selected from among methyl, ethyl, isopropyl and tert-butyl and methoxy.

Y ³ further preferably represents a group of the formula III.d, in which R ¹ and R ^x "independently of one another are dC ₄ alkyl or C ¹ -C ₄ alkoxy. In particular, R ¹ and R ^x " are independently selected from methyl , Ethyl, isopropyl, tert-butyl, methoxy and alkoxycarbonyl, preferably methoxycarbonyl. In these compounds, the radicals R "to R ^xι are particularly preferably hydrogen.

Y ³ further preferably represents a group of the formula III. e in which R ¹ and R ^x "independently of one another are dC ₄ alkyl or CC ₄ alkoxy. In particular, R ¹ and R ^x " are independently selected from methyl, ethyl, isopropyl, tert-butyl and methoxy. In these compounds, the radicals R "to R ^xι are particularly preferably hydrogen.

Y ³ furthermore preferably stands for a group of the formula IIIf, in which Z stands for a dC - alkylene group which has at least one alkyl, cycloalkyl or aryl substituent. Z particularly preferably represents a methylene group which has two CC alkyl radicals, especially two methyl radicals. Especially preferably, the radicals R ¹ and R ^vι in these compounds "are independently CC ₄ alkyl or d-C alkoxy. In particular, R ¹ and R ^VIII" are independently selected from methyl, ethyl, isopropyl, tert-butyl and methoxy. The radicals R ¹¹ , R ¹ ", R ^IV , R ^V , R ^VI and R ^v " preferably represent hydrogen.

Y ³ further preferably represents a group of the formula III. g, wherein R ¹ , R ^{1 '} , R ", R"^' , R ¹ "and R ¹ "^'are hydrogen.

Y ³ further preferably represents a group of the formula III. g, wherein R "and R ^{11 '} together represent an oxo group or a ketal thereof and the remaining radicals represent hydrogen. Y ³ further preferably represents a group of the formula III. h, wherein R ¹ , R ^{1 '} , R ", R ^11' , R ¹ " and R ¹ "^'are hydrogen.

Y ³ further preferably represents a group of the formula III. h, wherein R "and R ^{11 '} together represent an oxo group or a ketal thereof and the remaining radicals represent hydrogen.

Y ³ further preferably represents a group of the formula III. i, wherein R ¹ , R ¹ , R ", R ^{11 '} , R ¹ ", R ¹ "^' , R ^ιv and R ^{ι 'are} hydrogen.

Y ³ further preferably represents a group of the formula III. k, where R ¹ , R ^{1 '} , R ", R", R ¹ ", R ¹ "^' , R ^ι and R ^{ιv 'are} hydrogen.

Y ³ further preferably represents a group of the formula III. I, wherein R ¹ , R ^{1 '} , R ", R ^11' , R ^IN , R '"^' , R ^ιv and R ^{ιv 'are} hydrogen.

Y ³ further preferably represents a group of the formula III. m, wherein R ¹ , R ^{1 '} , R ", R ^11' , R ¹ ", R " ^{1 '} , R ^ιv and R ^{ιv' are} hydrogen.

Y ³ further preferably represents a group of the formula III. n, wherein R ¹ , R ^{1 '} , R ", R ^11' , R ¹ ", R '"^' , R ^ιv and R ^{ιv 'are} hydrogen.

Y ³ further preferably represents a group of the formula III. n, wherein one of the radicals R ¹ to R ^{ιv is} dC ₄ alkyl or dC ₄ alkoxy. In this case, at least one of the radicals R ¹ to R ^{ιv is} particularly preferably methyl, ethyl, isopropyl, tert-butyl or methoxy.

Furthermore, Y ³ preferably represents a group of the formula III.o, in which R ¹ , R ", R ¹ " and R ^{ιv represent} hydrogen.

Y ³ further preferably represents a group of the formula III.o, in which one of the radicals R ¹ , R ", R ¹ " or R ^{ιv represents} CC ₄ -alkyl or CC ₄ -alkoxy. One of the radicals R ¹ to R ^ιv then particularly preferably represents methyl, ethyl, tert-butyl or methoxy.

Y ³ further preferably represents a group of the formula III. p, wherein R ¹ and R ^vι independently of one another are dC ₄ alkyl or dC alkoxy. R ¹ and R ^v are particularly preferably selected independently of one another from methyl, ethyl, isopropyl, tert-butyl and methoxy. In these compounds, R ", R ¹ ", R ^ι and R ^v are particularly preferably hydrogen. Furthermore, the compounds III are preferably. p R ¹ , R ¹ ", R ^{, v} and R ^vι independently of one another for CC ₄ -alkyl or dC ₄ -alkoxy. Particularly preferred are R ¹ , R ¹ ", R ^ιv and R ^vι then independently selected from methyl, ethyl , Isopropyl, tert-butyl and methoxy. Furthermore, Y ³ preferably represents a group of the formula III.q, in which R ¹ and R ^vι independently of one another are CC ₄ alkyl or C ¹ -C ₄ alkoxy. R ¹ and R ^v are particularly preferably selected independently of one another from methyl, ethyl, isopropyl, tert-butyl and methoxy. In these compounds R ", R ¹ ", R ^ιv and R ^v are particularly preferably hydrogen. Furthermore, in these compounds R ¹ "and R ^lv independently of one another are CC ₄ alkyl or dC ₄ alkoxy. Particularly preferred are R ¹ " and R ^ιv independently of one another selected from methyl, ethyl, isopropyl, tert-butyl and methoxy.

Y ³ further preferably represents a group of the formula III. r, III. s or III.t, where Z is CH ₂ , C ₂ H ₂ or C ₂ H ₄ .

In the compounds of the formulas III. r, lll.s and lll.t are equally possible for the shown bonds to the bridged groups endo and exo.

The procedural design of the method according to the invention is explained in more detail below:

The discharge from the first reaction zone is subjected to a one- or multi-stage separation operation, at least one stream containing the main amount of the hydroformylation product and a stream consisting essentially of unreacted olefin and optionally saturated hydrocarbon being obtained. Saturated hydrocarbons originate, for example, from the olefin-containing feed used for the hydroformylation, which can contain these as an admixture, or to a small extent from the hydrogenation of the olefin used. Depending on the discharge and separation processes used, further streams may be obtained, such as waste gases containing synthesis gas, high-boiling by-products of hydroformylation and / or streams containing hydroformylation catalyst, which - if appropriate after working up - are wholly or partly returned to the first reaction zone or discharged from the process ,

A liquid discharge is preferably removed from the first reaction zone (liquid discharge process). The main components of this liquid discharge are:

i) the hydroformylation product, d. H. the aldehydes already produced in the first reaction zone from the olefin or olefin mixtures used,

ii) the high-boiling by-products of hydroformylation, as z. B. result from the aldol reaction of the aldehydes formed,

iii) the homogeneously dissolved first hydroformylation catalyst,

iv) unreacted olefins, v) low-boiling components, such as alkanes, and

vi) dissolved synthesis gas.

If an inert solvent, such as toluene or xylene, is used for the hydroformylation, this is also contained in the liquid discharge from the first reaction zone. As a rule, the by-products formed in the hydroformylation (e.g. by aldol condensation) and boiling higher than the hydroformylation product are used as solvents.

The liquid hydroformylation discharge from the first reaction zone is preferably subjected to a two-stage degassing for working up. The first degassing stage can be a rest and / or relaxation stage. In the simplest version of the first degassing stage as a resting zone, the liquid hydroformylation discharge is transferred from the first reaction zone to a container which is under the pressure of the reaction zone. This involves separation into a first liquid phase and a first gas phase. A suitable device for removing entrained droplets (demister) can be provided to separate the first gas phase without any liquid components.

The liquid hydroformylation effluent from the first reaction zone is particularly preferably subjected to a two-stage expansion for working up. The hydroformylation in the first reaction zone is preferably carried out at a pressure in the range from 5 to 50 bar. The liquid hydroformylation output from the first reaction zone is preferably expanded in a first expansion stage to a pressure which is 0.1 to 20 bar below the reactor pressure. This involves separation into a first liquid phase and a first gas phase. The first liquid phase is preferably relaxed in a second relaxation stage to a pressure which is lower than the pressure in the first relaxation stage. It is separated into a second liquid phase and a second gas phase.

The partial relaxation in the first expansion stage can take place, for example, in a conventional pressure separator. The first gas phase obtained essentially consists of synthesis gas and possibly small proportions of unreacted olefin and / or low-boiling components (saturated hydrocarbons). The first gas phase can be recycled in the process according to the invention or independently of it in other processes. For example, usually after compression to the reactor pressure, it can be returned to the reactor or, depending on the amount, partially or completely fed to thermal recycling.

The first liquid phase separated in the first expansion stage is then usually discharged as a liquid stream from the expansion vessel and expanded in a second expansion stage to a pressure which is lower than the pressure of the first relaxation level. In the second expansion stage, the pressure is preferably expanded to a pressure in the range from 0 to 10 bar, preferably from 0.1 to 5 bar. The pressure in the second relaxation stage is generally 2 to 20 bar, in particular 3 to 15 bar, lower than the pressure in the first relaxation stage.

The first liquid phase obtained from the first rest / relaxation stage is separated into a second liquid phase and a second gas phase in the second relaxation stage (degassing stage). The second liquid phase contains the by-products boiling higher than the hydroformylation product, the homogeneously dissolved first hydroformylation catalyst and part of the hydroformylation product. The second gas phase contains the unreacted olefin, saturated hydrocarbons and also part of the hydroformylation product.

In a preferred embodiment, the second relaxation stage is carried out as a combination of the relaxation step (flash) with a thermal separation step. This thermal separation step can be, for example, a distillation. For the distillation, the second liquid phase and second gas phase from the second expansion step are preferably conducted in countercurrent and brought into particularly intimate contact (stripping). Second relaxation step and thermal separation step can be in separate devices or advantageously in a single device, e.g. B. a so-called "flash / strip column".

When the second relaxation stage is designed with a separate thermal separation, the first liquid phase discharged from the first relaxation stage can first be expanded in a flash container. The resulting second gas phase is passed into the bottom or the lower part of a downstream distillation column. The (second) liquid phase from the flash tank is fed to this distillation column above the gas phase feed. For this purpose, the (second) liquid phase from the flash container of this distillation column e.g. can be supplied at or just below the head. For this purpose, the second liquid phase can be heated beforehand, for example in a heat exchanger. The second liquid phase is preferably heated to a temperature which is approximately 10 ° C. to 120 ° C. above the temperature of the liquid phase in the flash container (in the second relaxation stage). Suitable as a column are the usual distillation columns known to the person skilled in the art. B. filled with packing, packing or internals for an intensive gas / liquid exchange.

When the second expansion stage is designed as a “flash / strip column”, the first liquid phase discharged from the first expansion stage is fed into an area above the bottom and below the top of the flash / strip column, and is expanded in the process. The separation into the The second gas phase and the second liquid phase are preferably fed in within the lower half, in particular within the lower third of the flash / strip column A liquid stream is withdrawn from the flash / strip column and fed back to the column at or below the top. Thus, the liquid phase descending is directed towards the second gas phase for stripping. To do this, the liquid phase can be heated beforehand. The liquid phase drawn off from the sump is preferably heated to a temperature which is approximately 10 ° C. to 120 ° C. above the temperature of the sump. The columns used preferably have internals in the upper region, in particular within the upper third, for intensive gas / liquid exchange.

Both when designing the second expansion stage with separate thermal separation and when using a flash / strip column, a liquid phase containing the dissolved first hydroformylation catalyst and the by-products of the hydroformylation product boiling higher than the hydroformylation product and a hydroformylation product, the unreacted olefin and third gas phase containing saturated hydrocarbons obtained.

The third liquid phase can, if appropriate after the high boilers have been separated off in order to avoid their accumulation, be returned to the first reaction zone.

The third gas phase obtained in the second expansion stage (strip) is subjected to a separation into a fraction essentially containing the hydroformylation product and a fraction containing essentially unreacted olefin and low-boiling components. For this purpose, the third gas phase can be subjected to fractional condensation. The third gas phase can still be fully condensed and then subjected to thermal separation. The hydroformylation product is used for further use, as described below. After the condensation, the unreacted olefin and low-boiling component-containing fraction can be fed as a liquid stream into the second reaction zone. In a special embodiment, this fraction is subjected to an additional work-up in order to separate off at least some of the inert components (saturated hydrocarbons) contained. For this purpose, the fraction can, for example, be subjected to another fractional condensation or a complete condensation with subsequent distillation.

In summary, step b) is preferably an embodiment according to which one

b1) the liquid discharge from the first reaction zone, which contains as essential components the hydroformylation product, by-products boiling higher than the hydroformylation product, the homogeneously dissolved first hydroformylation catalyst, unreacted olefin, saturated hydrocarbons and unreacted synthesis gas, subjecting the process to degassing, if appropriate the Pressure and / or temperature relative to the reaction zone and which results in a first gas phase essentially comprising the unreacted synthesis gas and a first by-product boiling substantially the hydroformylation product, the by-products boiling higher than the hydroformylation product, the homogeneously dissolved first hydroformylation catalyst, unreacted olefin and saturated hydrocarbon-containing liquid phase,

b2) recycles the first gas phase,

b3) the first liquid phase is depressurized, the pressure compared to the first degassing being reduced to such an extent that a second gas phase containing the unreacted olefin, saturated hydrocarbons and part of the hydroformylation product and a second by-product boiling higher than the hydroformylation product homogeneously dissolved first hydroformylation catalyst and a liquid phase containing part of the hydroformylation product result,

b4) the second gas phase is fed into the bottom or the lower part of a column and the second liquid phase, if appropriate after heating, is fed in liquid form above the feed of the gas phase into this column and counteracts the gas phase,

b5) at the bottom of the column, a third liquid phase essentially comprising the dissolved first hydroformylation catalyst and the by-products of the hydroformylation boiling higher than the hydroformylation product is withdrawn and at the top of the column a third gas phase which contains the unreacted olefin and saturated hydrocarbons is drawn off,

b6) the third liquid phase, optionally after separation of at least some of the by-products boiling higher than the hydroformylation product, is returned to the first reaction zone, and

b7) subjecting the third gas phase to working up to obtain a fraction essentially containing the hydroformylation product and a fraction essentially containing the unreacted olefin and saturated hydrocarbons.

The discharge from the second reaction zone can in principle be worked up by the processes described for the first reaction zone. For this purpose, the discharge is preferably subjected to a multi-stage separation operation as described above, at least one stream containing the main amount of the second hydroformylation product and optionally further streams being obtained. In a suitable embodiment, the discharge from the second reaction zone separates a stream consisting essentially of saturated hydrocarbons and possibly a small proportion of unreacted olefins. The method according to the invention then preferably comprises the following steps, after which one additionally

d) a stream consisting essentially of saturated hydrocarbons and possibly a small proportion of unreacted olefin is separated from the discharge from the second reaction zone,

e) if appropriate, the stream obtained in step d) is separated by rectification into an olefin-enriched and an olefin-depleted fraction, and the olefin-enriched fraction is at least partially returned to the first and / or the second reaction zone

f) the olefin-depleted fraction obtained in step d) or the one obtained in step e) is recycled.

The rectification in step e) usually takes place at low temperature and / or elevated pressure, the exact temperature and / or pressure conditions depending on factors such as the number of carbon atoms in the olefin / saturated hydrocarbon to be separated, etc. The rectification is generally carried out in a column which is provided with a sufficiently large number of rectification trays. Columns for such separation tasks are known per se and z. B. used for the separation of olefins and saturated hydrocarbons contained in the cracked gas of a steam cracker. An olefin-enriched fraction can expediently be taken off at the top or top of the column and an olefin-depleted fraction at the bottom or bottom of the column. The olefin-enriched fraction, which, if desired, can still contain proportions of saturated hydrocarbons, can e.g. can be returned as a stream to the first or second reaction zone or used as a feed for other chemical reactions. The olefin-depleted fraction is removed from the system. You can e.g. B. burned or as a feedstock for chemical reactions or z. B. serve as a feed in the steam cracker.

The recycling in step f) includes, for example, thermal recycling, use for synthesis gas production or use as a cracker feed.

The product streams obtained from the discharges from the first and second reaction zones can be immediately used for further reaction, e.g. B. for the production of propylheptanol. If desired, they can also be worked up further by customary methods known to those skilled in the art, such as, B. by distillation, and then processed. An advantageous embodiment of the method according to the invention is shown in FIG. 1 and is explained below.

1 shows a schematic illustration of the method according to the invention using the liquid discharge method. System details which are self-evident and which are not required to illustrate the method according to the invention have been omitted for reasons of clarity.

According to FIG. 1, an olefin-containing feed (10a) which contains olefin to be hydroformylated and optionally saturated hydrocarbon, and synthesis gas recirculated through the pipeline (10b) and hydroformylation catalyst recirculated through the pipeline (13) is fed into the reactor (1), if appropriate, after a high boiler discharge, not shown, fed in and hydroformylated there up to a partial conversion. A liquid discharge is withdrawn from the reactor and contains as essential components the hydroformylation product, by-products boiling higher than the hydroformylation product, the homogeneously dissolved first hydroformylation catalyst, unreacted olefin, saturated hydrocarbons and unreacted synthesis gas. The current is partially released in the pressure separator (2), a phase separation into a gaseous portion, which essentially consists of synthesis gas, and a liquid portion. The synthesis gas is called gaseous

Current (1 1) removed and can optionally be fed again to the hydroformylation. The liquid portion is fed to the flasher (3) and separated into a liquid stream (12a) and a gaseous stream (12b). The liquid stream is fed in at the top and the gaseous stream is fed into the bottom of the stripping column (4) and is subjected to a stripping distillation. At the bottom of the column (4), the first catalyst system is removed (13), which, if appropriate after further work-up to separate high-boiling by-products, is passed back into the hydroformylation reactor (1). The mixture of hydroformylation product, olefin and saturated hydrocarbon (14) taken off at the top is condensed and passed into the distillation column (5). In the swamp of the

Distillation column (5), the hydroformylation product (15) is removed, which can then be worked up further. The mixture of olefin and optionally saturated hydrocarbon (16) taken off at the top is fed in liquid to the second hydroformylation reactor (6) after intermediate condensation. In addition, the second hydroformylation reactor (6) is fed through the pipeline (17) synthesis gas and the second catalyst system returned through the pipeline (20) and hydroformylated there until the desired conversion. A liquid discharge is withdrawn from the reactor (6) and fed into the pressure separator (7). The current is partially released in the pressure separator (7), a phase separation into a gaseous portion, which essentially consists of synthesis gas, and a liquid portion. The synthesis gas is withdrawn as a gaseous stream (18) and can optionally be returned to the hydroformylation. The liquid portion is fed to the flasher (8) and separated into a liquid stream (19a) and a gaseous stream (19b). The liquid stream is at the top and the gaseous stream at the bottom of the The bottom of the stripping column (9) was fed in and subjected to a stripping distillation. At the bottom of the column (9), the second catalyst system is removed (20), which, if appropriate after further work-up to separate high-boiling by-products, is passed back into the hydroformylation reactor (6). The mixture of hydroformylation product, saturated hydrocarbon and any residual amounts of olefin (21) taken off at the top is condensed and passed into the distillation column (10). In the bottom of the distillation column (10), the hydroformylation product (22) is removed, which can then be worked up further. The hydrocarbon (23) taken off at the top can be discharged or fed to a further separation in order to recover olefin still present.

If desired, in the method according to FIG. 1, flasher (3) and strip column (4) and / or flasher (8) and strip column (9) can be carried out in a single apparatus, a so-called flash / strip column.

Another object of the invention is a process for the preparation of 2-propylheptanol, in which

i) subjecting butene or a C-hydrocarbon mixture containing butene to hydroformylation by the process described above,

ii) if appropriate, subjecting the hydroformylation product to a separation to obtain a fraction enriched in n-valeraldehyde,

iii) subjecting the hydroformylation product obtained in step i) or the n-valeraldehyde-enriched fraction obtained in step ii) to an aldol condensation,

iv) the products of the aldol condensation are hydrogenated catalytically to alcohols with hydrogen, and

v) optionally subjecting the hydrogenation products to separation to obtain a fraction enriched in 2-propylheptanol.

In step i), a rhodium / triphenylphosphine catalyst is preferably used as the first hydroformylation catalyst. In step i), a hydroformylation catalyst which comprises at least one complex of a metal from subgroup VIII with at least one ligand of the general formula II is preferably used as the second hydroformylation catalyst. With regard to suitable and preferred ligands of the formula II, reference is made to the previous statements.

i) hydroformylation Suitable starting materials for the hydroformylation are both essentially pure 1-butene and mixtures of 1-butene with 2-butene and technically available C ₄ hydrocarbon streams which contain 1-butene and / or 2-butene. The C ₄ cuts described above are preferred and are referred to here.

The two-stage hydroformylation process according to the invention is advantageously suitable for the use of C ₄ cuts which contain 1-butene in a mixture with 2-butene. In the first stage, a catalyst is used which is capable of hydroformylating 1-butenes with high n-selectivity. In the second stage, a catalyst is used which is capable of isomerizing hydroformylation of 2-butene with high n-selectivity.

With regard to suitable and preferred hydroformylation catalysts, activating agents, solvents, reaction conditions and reactors for the hydroformylation in step i), reference is made in full to the previous general remarks on hydroformylation.

ii) separation

According to a suitable process variant, the combined product-enriched fractions obtained in step i) are subjected to a further separation in order to obtain a fraction enriched in n-valeraldehyde. The hydroformylation product is separated into an n-valeraldehyde-enriched fraction and an n-valeraldehyde-depleted fraction by conventional methods known to those skilled in the art. The distillation using known separation apparatuses, such as distillation columns, e.g. B. tray columns, which can be equipped with bells, sieve plates, sieve trays, valves etc. if desired, evaporators, such as thin-film evaporators, falling film evaporators, wiper blade evaporators etc.

iii) aldol condensation

Two molecules of C ₅ aldehyde can be condensed to form α, β-unsaturated Cio aldehydes. The aldol condensation takes place in a manner known per se, for. B. by the action of an aqueous base such as sodium hydroxide solution or potassium hydroxide solution. Alternatively, a heterogeneous basic catalyst, such as magnesium and / or aluminum oxide, can also be used (cf., for example, EP-A 792 862). The condensation of two molecules of n-valeraldehyde results in 2-propyl-2-heptenal. If the hydroformylation product obtained in step i) or after the separation in step ii) has further C ₅ aldehydes, such as 2-methylbutanal and optionally 2,2-dimethylpropanal or 3-methylbutanal or traces of other aldehydes, these also react in an aldol condensation, which then results in the condensation products of all possible aldehyde combinations, for example 2-propyl-4-methyl-2-hexenal. A portion of these condensation products, e.g. B. up to 30 wt .-%, is an advantageous Further processing into 2-propylheptanol-containing C ₁₀ alcohol mixtures which are suitable as plasticizer alcohols is not contrary.

iv) hydrogenation

The products of the aldol condensation can be catalytically hydrogenated with hydrogen to -C ₀ alcohols, such as in particular 2-propylheptanol.

For the hydrogenation of the C ₁₀ aldehydes to the Cio-alcohols, the catalysts of the hydroformylation are in principle also usually suitable at a higher temperature; however, more selective hydrogenation catalysts are generally preferred, which are used in a separate hydrogenation stage. Suitable hydrogenation catalysts are generally transition metals, such as. B. Cr, Mo, W, Fe, Rh, Co, Ni, Pd, Pt, Ru etc. or mixtures thereof, which increase the activity and stability on supports such. B. activated carbon, aluminum oxide, diatomaceous earth, etc. can be applied. To increase the catalytic activity, Fe, Co and preferably Ni, also in the form of the Raney catalysts, can be used as a metal sponge with a very large surface area. The hydrogenation of the cio-aldehydes takes place depending on the activity of the catalyst, preferably at elevated temperatures and elevated pressure. The hydrogenation temperature is preferably around 80 to 250 ° C., and the pressure is preferably around 50 to 350 bar.

The crude hydrogenation product can by conventional methods, e.g. B. by distillation to the C ₁₀ alcohols.

v) separation

If desired, the hydrogenation products can be subjected to a further separation to obtain a fraction enriched in 2-propylheptanol and a fraction depleted in 2-propylheptanol. This separation can be carried out by customary methods known to those skilled in the art, such as, for. B. by distillation. The 2-propylheptanol obtained can be processed further into plasticizers by customary processes known to those skilled in the art.

The invention is illustrated by the following, non-limiting examples.

Examples

The following ligands were used:

Ligand I) triphenylphosphine

Ligand II

The ligand II was according to a literature specification by Veen et al. in Angew. Chem. Int. Ed. 1999, 38, 336.

Ligand III

Ligand III was produced in accordance with WO 01/58589.

Ligand IV

Ligand IV was synthesized in accordance with WO 02/083695.

Ligand V

Ligand V was synthesized in accordance with WO 03/018192.

Ligand VI

Synthesis of ligand VI:

6.8 g (52 mmol) of 3-methylindole (Skatol) were placed in 400 ml of absolute tetrahydrofuran (THF) under argon, cooled to -75 ° C. and then mixed with 40 ml (288 mmol) of triethylamine. Then 2.4 ml (28 mmol) PCI ₃ were slowly added at -75 ° C. The reaction mixture was brought to room temperature and then stirred at room temperature for 16 h. ( ³¹ P NMR (crude) δ = 99 (s) and 100 (s)). Then 2.88 g (10.7 mmol) of 2,2'-dihydroxy-3,3 ', 4,4', 6,6'-hexamethylbiphenol (obtained according to DE 103 052 25.9) in 30 ml of absolute THF were within was added dropwise at room temperature from 6 h and the reaction mixture was stirred at room temperature overnight ( ³¹ P-NMR (crude) δ = 100 (s) chelating ligand (integral: 10) and 125 (s) mono ligand (integral: 2)). The precipitated colorless solid (triethylamine hydrochloride) was suctioned off through a protective gas frit, the solvent was distilled off in vacuo at 40 ° C., the residue was slurried twice with pentane and then dried in vacuo, leaving a sticky, slightly yellow solid. This solid is suspended in methanol at 50 ° C., then suction filtered through a protective gas frit, then washed twice with pentane and then dried in vacuo. 4.2 g (52% of theory) of product were obtained. MS (ionization: APCI): m / z = 850

¹ H NMR (C ₆ D ₆ , 360 MHz, 298K) δ = 1.41 (s, CH ₃ , 6H), 1.54 (s, CH ₃ , 6H), 2.01 (s, CH ₃ , 6H), 2.07 (s, CH ₃ , 6H), 2.10 (s, CH ₃ , 6H), 6.39 (s, "Biphenol-H", 2H), 7.05 -7.10 (m, Skat-H (H5 + H6), 8 H) , 7.33 (br s, Skat-H (H2), 4H), 7.37-7.41 (m, 2H), 7.59-7.61 (m, 2H), 7.78-7.81 (m, 2H): signals in the range 7.37-7.81 ( Skat-H (H4 and H7)).

³¹ P NMR (C ₆ D ₆ , 146 MHz, 298K)

<J = 103 (s).

Hydroformylierungsbeispiele

A raffinate II of the following composition was used as the olefin mixture for the hydroformylation:

Isobutane 1.7%, n-butane 12.4%, trans-2-butene 31.7%, cis-2-butene 16.8%, 1-butene 35.1%, isobutene 2.4%

Example 1 :

1st stage: Rh / triphenylphosphine 2nd stage: Rh / ligand IV

1st stage:

6.4 mg Rh (CO) ₂ acac (acac = acetylacetonate) and 1.9 g triphenylphosphine were weighed in separately, dissolved in 5 g toluene, mixed and mixed at 90 ° C with 10 bar synthesis gas (CO: H ₂ = 1: 1) fumigated (preforming). After 1 h the pressure was released. Then 15 g of raffinate II (isobutane 1.7%, n-butane 12.4%, trans-2-butene 31.7%, cis-2-butene 16.8%, 1-butene 35.1%, isobutene 2.4%) was added by means of a pressure lock, a total pressure of 20 bar was set with synthesis gas (CO: H ₂ = 1: 1) and hydroformylated for 2 hours at 90 ° C. (95 ppm Rh). The autoclave was then cooled, carefully released via a cold trap, and both reaction outputs (reactor and cold trap) were analyzed using gas chromatography. The 1-butene conversion was 85%, the yield of valeraldehyde 38% and the linearity (n fraction) 78.0%. [The linearity (n component) is defined as the quotient from n-valeraldehyde to the sum of n-valeraldehyde and i-valeraldehyde multiplied by 100]. The composition of the liquid gas discharge in the cold trap was: isobutane 1%, n-butane 13.7%, trans-2-butene 48.2%, cis-2-butene 28.9%, 1-butene 8.2% , 2nd stage:

5 mg Rh (CO) ₂ acac (acac = acetylacetonate) and 191 mg Ligand IV were weighed in separately, dissolved in 5 g toluene each, mixed and mixed at 90 ° C with 10 bar synthesis gas (CO: H ₂ = 1: 2 ) fumigated (preforming). After 1 h the pressure was released. Then 7.3 g of liquid gas of the 1st stage (see above: isobutane 1%, n-butane 13.7%, trans-2-butene 48.2%, cis-2-butene 28.9%, 1-butene 8 , 2%) was added by means of a pressure lock, and a total pressure of 17 bar was set using synthesis gas (CO: H ₂ = 1: 2). The gas supply was then switched to synthesis gas (CO: H ₂ = 1: 1) in order to ensure a constant ratio of CO: H ₂ of 1: 2 in the reactor. The mixture was then hydroformylated for 4 hours at 90 ° C. (122 ppm Rh). The conversion of the 1-butene was 81%, the conversion of the 2-butene was 65%, the yield of valeraldehyde was 37% and the linearity (n content) was 93.9%.

The n proportion over both stages (1st stage: Rh / PPh ₃ ; 2nd stage: Rh / ligand IV) was 82.5%.

Example 2:

1st stage: Rh / Ligand II 2nd stage: Rh / Ligand V

1st stage:

6.3 mg Rh (CO) ₂ acac (acac = acetylacetonate) and 168 mg Ligand II were weighed in separately, dissolved in 5 g toluene, mixed and mixed at 90 ° C with 10 bar synthesis gas (CO: H ₂ = 1: 1 ) fumigated (preforming). After 1 h the pressure was released. Then 14.4 g of raffinate II were added by means of a pressure lock, a total pressure of 20 bar was set with synthesis gas (CO: H ₂ = 1: 1) and hydroformylated for 4 hours at 90 ° C. (102 ppm Rh). The autoclave was then cooled, carefully released via a cold trap, and both reaction outputs (reactor and cold trap) were analyzed using gas chromatography. The 1-butene conversion was 79%, the yield of valeraldehyde 33% and the linearity (n fraction) 96.5%. The composition of the liquid gas discharge in the cold trap was: isobutane 0.7%, n-butane 12.4%, trans-2-butene 46.9%, cis-2-butene 19.3%, 1-butene 10.7% ,

2nd stage:

5 mg Rh (CO) ₂ acac (acac = acetylacetonate) and 168 mg Ligand V were weighed in separately, dissolved in 5 g toluene each, mixed and mixed at 90 ° C with 10 bar synthesis gas

(CO: H ₂ = 1: 2) fumigated (preforming). After 1 h the pressure was released. Then 6.1 g of liquefied gas from the 1st stage (see above: isobutane 0.7%, n-butane 12.4%, trans-2-butene 46.9%, cis-2-butene 19.3%, 1- Butene 10.7%) was added using a pressure lock, and a total pressure of 17 bar was set using synthesis gas (CO: H ₂ = 1: 2). The gas supply was then switched to synthesis gas (CO: H ₂ = 1: 1) to ensure a constant ratio of CO: H ₂ of 1: 2 in the reactor. The mixture was then hydroformylated for 4 hours at 90 ° C. (114 ppm Rh). The conversion of the 1-butene was 83%, the conversion of the 2-butene was 59%, the yield of valeraldehyde was 34% and the linearity (n content) was 95.6%.

The n proportion over both stages (1st stage: Rh / Ligand II; 2nd stage: Rh / Ligand V) was 96.2%.

Example 3:

1st stage: Rh / Ligand II

2nd stage: Rh / Ligand VI

1st stage:

6 mg Rh (CO) ₂ acac and 11 mg Ligand II were weighed in separately, dissolved in 5 g toluene each, mixed and gassed at 90 ° C with 10 bar synthesis gas (CO: H ₂ = 1: 1) (preforming). After 1 h the pressure was released. Then 14.6 g of raffinate II were added by means of a pressure lock, a total pressure of 20 bar was set with synthesis gas (CO: H ₂ = 1: 1) and hydroformylation (97 ppm Rh) at 90 ° C. for 4 h. The autoclave was then cooled, carefully released via a cold trap, and both reaction outputs (reactor and cold trap) were analyzed using gas chromatography. The 1-butene conversion was 65%, the yield of valeraldehyde 15% and the linearity (n content) 98.4%. The composition of the liquid gas discharge in the cold trap was: isobutane 0.7%, n-butane 11.8%, trans-2-butene 46.1%, cis-2-butene 28.5%, 1-butene 13.0%.

2nd stage:

5 mg Rh (CO) ₂ acac and 165 mg Ligand VI were weighed in separately, dissolved in 5 g toluene each, mixed and gassed at 90 ° C with 10 bar synthesis gas (CO: H ₂ = 1: 2) (preforming). After 1 h the pressure was released. Then 7.8 g of liquid gas of the 1st stage (see above: isobutane 0.7%, n-butane 11.8%, trans-2-butene 46.1%, cis-2-butene 28.5%, 1-butene 13.0%) were added by means of a pressure lock and a total pressure of 17 bar was set with synthesis gas (CO: H ₂ = 1: 2). The gas supply was then switched to synthesis gas (CO: H ₂ = 1: 1) in order to ensure a constant ratio of CO: H ₂ of 1: 2 in the reactor. The mixture was then hydroformylated at 90 ° C. for 4 h (1 1 1 ppm Rh). The conversion of the 1-butene was 84%, the conversion of the 2-butene was 38%, the yield of valeraldehyde was 28% and the linearity (n content) was 96.2%.

The n proportion over both stages (1st stage: Rh / ligand I; 2nd stage: Rh / ligand VI) was 97.3%.

Claims

claims

1. Process for the preparation of hydroformylation products of olefins, in which a) an olefin-containing feed as well as carbon monoxide and hydrogen are fed into a first reaction zone and reacted in the presence of a first catalyst system, b) an essentially unreacted olefins from the discharge from the first reaction zone and optionally separating the saturated hydrocarbon liquid stream, c) feeding the liquid stream obtained in step b) and carbon monoxide and hydrogen into a second reaction zone and reacting it in the presence of a second catalyst system.

2. The method according to claim 1, wherein in step b) an essentially liquid discharge is removed from the first reaction zones and subjected to a two-stage expansion.

3. The method according to any one of claims 1 or 2, in which in step b) b1) the liquid discharge from the first reaction zone, the essential components of the hydroformylation product, the by-products boiling higher than the hydroformylation product, the homogeneously dissolved first hydroformylation catalyst, unreacted Contains olefin, saturated hydrocarbons and unreacted synthesis gas, subjected to degassing, the pressure and / or the temperature relative to the reaction zone being reduced, if appropriate, and wherein a first gas phase essentially containing the unreacted synthesis gas and a first essentially the hydroformylation product, higher by-products boiling as the hydroformylation product, the homogeneously dissolved first hydroformylation catalyst, unreacted olefin and liquid hydrocarbon-containing liquid result, b2) the first gas phase is recycled, b3) the first liquid phase ssige phase of a relaxation subjects, wherein the pressure against the first degassing is reduced until a second, the unreacted olefin, saturated hydrocarbons and a portion of the gas phase hydroformylation product containing and a second which is higher than that of the hydroformylation boiling by-products, the liquid phase containing the homogeneously dissolved first hydroformylation catalyst and part of the hydroformylation product results, b4) feeding the second gas phase into the bottom or the lower part of a column and the second liquid phase, optionally after heating, in liquid form above the feed of the gas phase into it Feeds column and leads to the gas phase, b5) at the bottom of the column withdraws essentially the dissolved first hydroformylation catalyst and the byproducts of the hydroformylation product boiling higher than the hydroformylation product and withdrawn at the top of the column a hydroformylation product, the unreacted olefin and saturated Withdrawing hydrocarbon-containing third gas phase, b6) recycling the third liquid phase, if appropriate after separating off at least some of the by-products boiling higher than the hydroformylation product, into the first reaction zone rt, and b7) subjecting the third gas phase to working up to obtain a fraction essentially containing the hydroformylation product and a fraction essentially containing the unreacted olefin and saturated hydrocarbons.

4. The method according to claim 3, wherein a flash / strip column is used to carry out steps b3) and b4) and wherein the first liquid phase is fed into an area above the bottom and below the top of the flash / strip column and expanded , a separation into the second gas phase and the second liquid phase takes place, a liquid stream is withdrawn from the bottom of the flash / strip column and fed back to the column at or below the top and is directed towards the second gas phase.

5. The method according to claim 1, in which additionally d) a stream consisting essentially of saturated hydrocarbon and possibly a small proportion of unreacted olefin is separated from the discharge from the second reaction zone, e) optionally the stream obtained in step d) into an olefin separates enriched and an olefin-depleted fraction, and at least partially returns the olefin-enriched fraction to the first and / or second reaction zone, and f) feeds the stream obtained in step d) or the olefin-depleted fraction obtained in step e) for recycling.

6. The method according to any one of the preceding claims, wherein the first catalyst system comprises at least one complex of a metal of subgroup VIII of the Periodic Table of the Elements with at least one organic phosphorus (III) compound as ligand.

7. The method according to claim 6, wherein the organic phosphorus (III) compound is selected from compounds of the formula PR ¹ R ² R ³ , wherein R ¹ , R ² and R ³ independently of one another for alkyl, cycloalkyl, heterocycloalkyl, aryl or hetaryl stand, the alkyl radicals 1, 2, 3, 4 or 5 substituents selected from cycloalkyl, heterocycloalkyl, aryl, hetaryl, alkoxy, cycloalkoxy, heterocycloalkoxy, aryloxy, hetaryloxy, COOH, carboxylate, SO ₃ H, sulfonate, NE ¹ E ² , NE E ² E ³⁺ X \ halogen, nitro, acyl or cyano, in which E ¹ , E ² and E ^{3 are} each the same or different radicals selected from hydrogen, alkyl, cycloalkyl or aryl and X ^" represents an anion equivalent, and wherein the cycloalkyl, heterocycloalkyl, aryl and hetaryl radicals can have 1, 2, 3, 4 or 5 substituents which are selected from alkyl and those previously for the alkyl radicals R ¹ , R ² and R ³ mentioned substituents, wherein R ¹ and R ² together with the phosphorate om to which they are attached can also represent a 5- to 8-membered heterocycle which is optionally additionally fused one, two or three times with cycloalkyl, heterocycloalkyl, aryl or hetaryl, the heterocycle and, if present, the fused groups can each independently carry one, two, three or four substituents which are selected from alkyl and the substituents mentioned above for the alkyl radicals R ¹ , R ² and R ³ . th.

8. The method of claim 6, wherein the first catalyst system comprises a complex of rhodium with triphenylphosphine as the ligand.

9. The method according to claim 6, wherein the organic phosphorus (III) compound is selected from chelate compounds of the formula R ¹ R ² PY -PR ¹ R ² , wherein R ¹ and R ^{2 have} the meanings given in claim 7 and Y ¹ for there is a divalent bridging group.

10. The method according to claim 9, wherein the bridging group Y ¹ selected from groups of the formula

wherein

R ', R ", R ^MI , R ^IV , R ^V and R ^vι independently of one another for hydrogen, alkyl, cycloalkyl, heterocycloalkyl, aryl, hetaryl, hydroxy, thiol, polyalkylene oxide, polyalkyleneimine, alkoxy, halogen, COOH, carboxylate, SO ₃ H, sulfonate, NE ⁶ E ⁷ , alkylene-NE ⁶ E ⁷ , trifluoromethyl, nitro, alkoxycarbonyl, acyl or cyano, in which E ⁶ and E ⁷ each denote the same or different radicals selected from hydrogen, alkyl, cycloalkyl and aryl, where two adjacent radicals R ¹ to R ^vι together with the carbon atoms of the benzene nucleus to which they are attached can also represent a condensed ring system with 1, 2 or 3 further rings, and

R ^d and R ^{e are} independently hydrogen, alkyl, cycloalkyl, heterocycloalkyl, aryl or hetaryl.

11. The method of claim 9, wherein the bridging group Y is a group of the formula purple as defined in claim 16.

12. The method according to any one of the preceding claims, wherein the second catalyst system at least one complex of a metal of subgroup VIII of the Periodic Table of the Elements with at least one phosphorus chelate compound of general formula I.

R ^α - (X ¹ ) dP- (X ³ ) fY ² - (X ⁴ ) gP- (X ⁶ ) rR ^δ

as ligands, wherein

Y ^{2 represents} a divalent bridging group,

R ^α , R ^ß , R ^γ and R ^δ independently of one another represent alkyl, cycloalkyl, heterocycloalkyl, aryl or hetaryl, the alkyl radicals 1, 2, 3, 4 or 5 substituents selected from cycloalkyl, heterocycloalkyl, aryl, hetaryl, alkoxy, cycloalkoxy, heterocycloalkoxy, aryloxy, hetaryloxy, hydroxy, thiol, polyalkylene oxide, polyalkyleneimine, COOH, carboxylate, SO ₃ H, sulfonate, NE ¹⁰ E ¹¹ , NE ⁰ E ¹¹ E ¹²⁺ X ^" , halogen, nitro, acyl or cyano, in which E ¹⁰ , E ¹¹ and E ¹² each represent the same or different radicals selected from hydrogen, alkyl, cycloalkyl or aryl and X ^'represents an anion equivalent , and wherein the cycloalkyl, heterocycloalkyl, aryl and hetaryl radicals R ^α , R ^ß , R ^γ and R ^{δ may have} 1, 2, 3, 4 or 5 substituents which are selected from alkyl and those previously given for the alkyl radicals R. ^α , R ^ß , R ^γ and R ^δ substituents, or

R ^α and R ^ß and / or R ^γ and R ^δ together with the phosphorus atom and, if present, the groups X ¹ , X ² , X ⁵ and X ⁶ to which they are attached for a 5- to 8-membered group Heterocycle, which is optionally additionally fused one, two or three times with cycloalkyl, heterocycloalkyl, aryl or hetaryl, where the heterocycle and, if present, the fused groups can independently carry one, two, three or four substituents , which are selected from alkyl, cycloalkyl, heterocycloalkyl, aryl, hetaryl, hydroxy, thiol, polyalkylene oxide, polyalkyleneimine, alkoxy, halogen, COOH, carboxylate, SO ₃ H, sulfonate, NE ¹³ E ¹⁴ , NE ³ E ¹⁴ E ⁵⁺ X ^" , Nitro, alkoxycarbonyl, acyl or cyano, in which E ¹³ , E ¹⁴ and E ¹⁵ each represent the same or different radicals selected from hydrogen, alkyl, cycloalkyl and aryl and X ^{" represents} an anion equivalent,

X ¹ , X ² , X ³ , X ⁴ , X ⁵ and X ⁶ are selected independently of one another from O, S, SiR ^ε R ^ξ and NR ^η , where R ^e , R ^ξ and R ^η independently of one another for hydrogen, Alkyl, cycloalkyl, heterocycloalkyl, aryl or hetaryl, and d, e, f, g, h and i are independently 0 or 1.

13. The method according to any one of the preceding claims, wherein the second catalyst system at least one complex of a metal of subgroup VIII of the Periodic Table of the Elements with at least one phosphorus chelate compound of the general formula II

as ligands, wherein R ⁴ , R ⁵ , R ⁶ and R ⁷ independently of one another represent heteroatom-containing groups which are bonded to the phosphorus atom via an oxygen atom or an optionally substituted nitrogen atom or R ⁴ together with R ⁵ and / or R ⁶ together with R ^{7 form} a double bond form a heteroatom-containing group which are bonded to the phosphorus atom via two heteroatoms selected from oxygen and / or optionally substituted nitrogen, a and b independently of one another denote the number 0 or 1, and

Y ^{3 represents} a divalent bridging group with 2 to 20 bridging atoms between the flanking bonds, at least two bridging atoms being part of an alicyclic or aromatic group.

14. The method according to claim 13, wherein R ⁴ , R ⁵ , R ⁶ and R ^{7 are} independently selected from groups of formulas II.a to II. K

Alk -Alk Λ \ ^ COOAlk \\ ff w

(ll.a) (ii. b)

AlkOOC _^ / N _{x ^} COOAlk

/ \ AlkOOC COOAlk (II. C) (II. D)

: il.e): nf) (ii.g)

wherein

Alk is a C 1 -C ₄ alkyl group and R ⁹ , R ^h , R 'and R ^k independently of one another are hydrogen, dC ₄ alkyl, CC ₄ alkoxy, acyl, halogen, trifluoromethyl, dC ₄ alkoxycarbonyl or carboxyl.

15. The method according to claim 13, wherein R ⁴ and R ⁵ and / or R ⁶ and R ⁷ each together with the phosphorus atom to which they are attached, for a group of the general formula ILA

where k and I are independently 0 or 1,

Q together with the phosphorus atom and the oxygen atoms to which it is attached represents a 5- to 8-membered heterocycle which is optionally fused one, two or three times with cycloalkyl, heterocycloalkyl, aryl and / or hetaryl, where the fused groups independently of one another have one, two, three or four substituents selected from alkyl, alkoxy, cycloalkyl, aryl, halogen, hydroxy, thiol, polyalkylene oxide, polyalkyleneimine, COOH, carboxylate, SO ₃ H, sulfonate, NE ⁴ E ^S , Alkylene-NE ⁴ E ⁵ , nitro and cyano can carry and / or Q one, two or three substituents which are selected from alkyl, alkoxy, optionally substituted cycloalkyl and optionally substituted aryl. can and / or Q can be interrupted by 1, 2 or 3 optionally substituted heteroatoms.

16. The method according to any one of claims 13 to 15, wherein in the formula II, the bridging group Y ^{3 is} selected from groups of the formulas IIIa to III.t.

[lll.a) (III. b)

(III. E) R ¹ R

(III.f) (in.g)

Üii.h) (in. I] (III. K)

(III.o) (III. ⁾ (III.q)

IHI.r) (III. S) (III. T) where

R ¹ , R ^{1 '} , R ", R"^' , R " ¹ , R" ^{1 '} , R ^ιv , R ^ιv' , R ^v , R ^vι , R ", R ^vι ", R ^ιx , R ^x , R ^xι and R ^x "independently of one another for hydrogen, alkyl, cycloalkyl, heterocycloalkyl, aryl, hetaryl, hydroxy, thiol, polyalkylene oxide, polyalkyleneimine, alkoxy, halogen, SO ₃ H, sulfonate, NE ²² E ²³ , alkylene NE ²² E ²³ , Trifluoromethyl, nitro, alkoxycarbonyl, carboxyl, acyl or cyano, where E ²² and E ²³ are the same or different radicals selected from hydrogen, alkyl, cycloalkyl and aryl,

Z represents O, S, NR ¹⁵ or SiR ¹⁵ R ¹⁶ , where R ¹⁵ and R ¹⁶ independently represent hydrogen, alkyl, cycloalkyl, heterocycloalkyl, aryl or hetaryl, or Z represents a dC ₄ alkylene bridge which has a double bond and / or an alkyl, cycloalkyl, heterocycloalkyl, aryl or hetaryl substituent, or Z represents a C ₂ -C ₄ alkylene bridge which is interrupted by O, S or NR ¹⁵ or SiR ¹⁵ R ¹⁶ .

where in the groups of the formula IIIa two adjacent radicals R ¹ to R ^vl together with the carbon atoms of the benzene nucleus to which they are attached can also represent a condensed ring system with 1, 2 or 3 further rings,

where in the groups of formulas III to III. m two geminal residues R ¹ , R ^{1 '} ; R "

_R ιr. p ⁱⁱⁱ _{^ R} nr _unc j / _oc jer R ^ιv , R ^{ιv "can} also stand for oxo or a ketal thereof,

A ¹ and A ² independently of one another represent O, S, SiR ^a R ^b , NR ^C or CR ^d R ^e , where

R ^a , R ^b and R ^c independently of one another represent hydrogen, alkyl, cycloalkyl, heterocycloalkyl, aryl or hetaryl,

R ^d and R ^e independently of one another represent hydrogen, alkyl, cycloalkyl, heterocycloalkyl, aryl or hetaryl or the group R ^d together with another group R or the group R ^e together with another group R ^{e form} an intramolecular bridging group D. .

D for a double-bonded bridge group of the general formula

\ / \ / CC / \ is in the R ⁹ , R ^{9 '} , R ¹⁰ and R ^10' independently of one another represent hydrogen, alkyl, cycloalkyl, aryl, halogen, trifluoromethyl, carboxyl, carboxylate or cyano, where R ⁹ together with R ^{10 also represent} the binding proportion of a double bond between the two carbon atoms to which R ^{9 '} and R ^{10' are} bonded, and / or R ⁹ and R ¹⁰ together with the carbon atoms to which they are bonded, also for a 4- to 8-membered carbo- or Heterocycle, which is optionally additionally fused one, two or three times with cycloalkyl, heterocycloalkyl, aryl or hetaryl, where the heterocycle and, if present, the fused groups can independently carry one, two, three or four substituents, which are selected from alkyl, cycloalkyl, heterocycloalkyl, aryl, hetaryl, COOR ^f , COO ^" M ⁺ , SO ₃ R ^f , SO- ₃ M ⁺ , NE ²⁵ E ²⁶ , alkylene-NE ²⁵ E ²⁶ , NE ²⁵ E ²⁶ E ⁷⁺ X ^" , alkylene NE ²⁵ E ²⁶ E ²⁷⁺ X-, OR ^f , SR ^f , (CHR ⁹ CH ₂ O) _y R ^f , (CH ₂ N (E ²⁵ )) _y R ^f , (CH ₂ CH ₂ N (E ²⁵ )) _y R ^f , halogen, trifluoromethyl, nitro, acyl or cyano, in which

R ^f , E ²⁵ , E ²⁶ and E ²⁷ each represent the same or different radicals selected from hydrogen, alkyl, cycloalkyl or aryl,

R ^{9 represents} hydrogen, methyl or ethyl,

M ^{+ stands} for a cation, X ^"stands for an anion, and y stands for an integer from 1 to 120, and c is 0 or 1.

17. The method according to any one of the preceding claims, in which an olefin mixture is used which contains olefins with internal double bonds and olefins with terminal double bonds.

18. The method according to claim 17, in which an olefin mixture is used which contains 1 - butene and 2-butene.

19. A process for the preparation of 2-propylheptanol, in which i) butene or a C ₄ -hydrocarbon mixture containing butene is subjected to a hydroformylation as defined in one of claims 1 to 16 to give a hydroformylation product containing n-valeraldehyde, ii) if appropriate, subjecting the hydroformylation product to a separation to obtain a fraction enriched in n-valeraldehyde,

iii) subjecting the hydroformylation product obtained in step i) or the n-valeraldehyde-enriched fraction obtained in step ii) to an aldol condensation,

iv) the products of the aldol condensation are hydrogenated catalytically to alcohols with hydrogen, and

v) optionally subjecting the hydrogenation products to separation to obtain a fraction enriched in 2-propylheptanol.