EP1667950A1

EP1667950A1 - Method for the production of 1.7-octadiene and use thereof

Info

Publication number: EP1667950A1
Application number: EP04765331A
Authority: EP
Inventors: Volker BÖHM; Michael Röper; Jürgen STEPHAN; Regina Benfer; Markus Schubert; Jörn KARL; Klaus Ebel; Oliver LÖBER; Martin Volland
Original assignee: BASF SE
Current assignee: BASF SE
Priority date: 2003-09-25
Filing date: 2004-09-17
Publication date: 2006-06-14
Also published as: MXPA06002569A; CN1860086A; DE10344690A1; JP2007506691A; US20070083066A1; WO2005030681A1

Abstract

The invention relates to a method for the production of 1.7 octadiene by reacting metathesis of cyclohexene with ethylene. The invention also relates to the production of 1.10-decandiol by hydroformulating 1.7 octadiene produced according to said method. The invention further relates to a method for the production of muscone or olefinically unsaturated analogs thereof using 1.10 decandiol which is obtainable in said manner.

Description

Process for the preparation of 1, 7-octadiene and its use

description

The present invention relates to a process for the preparation of 1, 7-octadiene by metathesis of cyclohexene with ethylene. It also relates to processes for the preparation of 1, 10 decanedial or muscon or its olefinically unsaturated analogs using 1,7-octadiene prepared in this way.

α, ω-Diolefins are valuable starting materials for a large number of chemical syntheses. For example, they can be used in the context of homo- or copolymerization processes to obtain polymers with defined properties. In addition, they serve as starting materials for the production of α, co-diols, which in turn can be used in the context of polyester synthesis. In addition, the terminal double bonds of the α, ω-diolefins are also suitable for producing a variety of other functionalities. For example, double hydroformylation of the terminal double bonds gives dialdehydes.

A suitable synthetic access to the α, ω-diolefins is the ring opening metathesis of cyclic olefins in the presence of ethene (“ethenolysis”). In the context of this type of reaction, the ethenolysis of cyclohexene to 1, 7-octadiene assumes a certain exceptional position the in this case unfavorable equilibrium situation, this implementation has so far only succeeded in unsatisfactory yields and under economically less attractive conditions.

For example, D.L Crain et al. in Am. Chem. Soc. Div. Petrol. Chem. Prepr. 1972, 17 (4), E80 - E85 the ethenolysis of cyclohexene, which proceeds at a pressure of approx. 690 bar, a temperature of 125 ° C and a 9-fold molar excess of ethylene with a conversion of 6.8%.

DE-A 1 618 760 generally describes the ethenolysis of cyclic olefins in the presence of suitable transition metal catalysts. The ethenolysis of cyclohexene in the presence of a catalyst containing CoO and Mo0 ₃ at a pressure of 52 atm and 125 ° C. for 3 h gives 1,7-octadiene in a selectivity of approx. 23% of theory. Th.

No. 3,424,811 describes “disproportionation reactions” of cyclic with acyclic olefins in the presence of supported catalysts containing Mo or Re and an alkali metal.

DE-A 40 09 910 describes the use of organorhenium oxides on oxide supports as catalysts for the ethical metathesis of olefinic compounds. Accordingly, there is still an urgent need for a process which allows 1, 7-octadiene to be produced by ethenolysis of cyclohexene in an economically satisfactory manner and under conditions which can be carried out on an industrial scale.

A process for the preparation of 1,7-octadiene by metathesis of cyclohexene with ethylene has now been found, which is characterized in that the unreacted starting materials and any higher-boiling by-products obtained are recycled to the reaction mixture in purified form.

The process according to the invention is suitable for providing large amounts of 1,7-octadiene in a particularly economical manner. The inexpensive and readily available compounds cyclohexene and ethylene serve as starting materials. By recycling the unreacted purified starting materials and high-boiling by-products, cyclohexene can be converted into 1,7-octadiene in high yield.

Suitable starting materials for the process according to the invention are hydrocarbon mixtures containing cyclohexene, in particular those which consist largely of cyclohexene. Particularly suitable> t cyclohexene with a purity of about 90% to about 99.9%, preferably from about 95% to about 99.9%, particularly preferably from about 98% to about 99.9%. Cyclohexene, which contains up to about 1% of polar impurities, in particular oxigenates such as, for example, cyclohexanol and / or cyclohexanone or also peroxides, is advantageously used. Cyclohexene used with particular preference is essentially free of polar impurities. Advantageously, it is additionally subjected to a pre-cleaning according to methods known to the person skilled in the art. For example, it can be passed through a so-called guard bed, which consists of high-surface aluminum oxides, silica gels, aluminum silicates or molecular sieves. This protective bed serves to dry the starting materials used and to remove substances which can act as a catalyst poison in the subsequent metathesis step. Preferred adsorbent materials are, for example, Selexsorb CD ^® (Fa. Alcoa Inc.) and CDO and 3A-molecular sieves and NaX (13X). Cleaning is advantageously carried out in drying towers at temperatures and pressures which are chosen so that all components are in the liquid phase.

Ethylene with a purity of generally about 95 to about 99.99%, preferably about 98 to about 99.99% or even higher, is used as a further starting material. If necessary, it can also be pre-cleaned by suitable processes, for example by the processes described above for the purification of the cyclohexene. The reactants are usually used in a molar ratio of ethylene to cyclohexene of about 1: 1 to about 10: 1. A molar ratio of approximately 2: 1 to approximately 6: 1 is preferred, particularly preferably approximately 2: 1 to approximately 4: 1.

The starting substances are undiluted or by a diluent which is inert under the chosen reaction conditions, such as straight-chain, branched or cyclic hydrocarbons with 5 to 12 carbon atoms, e.g. Cyclohexane, cyclooctane, pentane, hexane, heptane, octane, nonane, decane, undecane and dodecane or higher hydrocarbons or mixtures thereof, diluted in a reactor corresponding to the selected temperature and pressure conditions, such as a pressurized gas vessel, a flow tube, a tubular reactor, a stirred tank, a trickle bed reactor, a bubble column, a stirred tank cascade, a loop reactor or in a column for reactive distillation. Within the scope of the method according to the invention. A tubular reactor in which a catalyst which accelerates the metathesis reaction is present in immobilized form is particularly preferred.

The reaction can also be carried out in parallel or alternately in two or more reactors. This procedure allows the process to be continued without interruption even when the catalyst systems used are regenerated in individual reactors.

Suitable catalysts are those which accelerate the reaction according to the invention under the selected conditions. Such catalysts are particularly suitable if they do not catalyze undesired isomerizations or only do so to a small extent. They usually contain one or different transition metals from groups Vl.b, Vll.b or VIII such as Re, W, Mo, Ru, Os, Ta or Nb as such in the form of their compounds or salts. In principle, they can be used in homogeneous as well as in heterogeneous form, but preferably in heterogeneous form. Examples of homogeneous catalysts are Ru-containing alkylidene complexes catalyzing alkene metathesis, as described, for example, in WO 03/011455, WO 00/71554, EP-A 0 921 129 or WO 97/06185. Suitable heterogeneous catalysts are, for example, those in which the catalytically active substance or compound is present in an amount of from about 0.1 to about 20% by weight, preferably from about 1 to about 15% by weight, based on the total weight of the finished catalyst a carrier, preferably on an oxidic carrier such as SiO ₂ , Al ₂ O ₃ or TiO ₂ or a mixed carrier such as SiO ₂ / Al ₂ O ₃ , B ₂ θ ₃ / SiO ₂ / Al ₂ O ₃ or Fe ₂ θ ₃ lA \ ₂ θ ₃ , preferably applied to Al ₂ O ₃ .

A catalyst which is particularly preferred in the process according to the invention contains, based on the total weight of the finished catalyst, about 6 to about 12% by weight of Re ₂ O ₇ applied to Al ₂ O ₃ as support material. The carrier material can be used in various forms, but advantageously in the form of balls, strands, spirals, rings or trilobes. Preferred are balls or strands with a diameter or a length of approximately 0.5 to approximately 5 mm, preferably approximately 1 to approximately 2 mm. In a particularly preferred embodiment, strands with a length of approximately 1.5 mm are used as the carrier material.

The catalytically active compound can be applied to the selected support in various ways known to those skilled in the art, e.g. by immersion impregnation, dry soaking or vapor deposition. To produce the preferred rhenium catalysts, the support is impregnated with an aqueous ammonium perrhenate solution or, preferably, with perrhenic acid. In addition to aqueous solutions, solutions containing organic solvents such as e.g. Use dioxane, lower alcohols, ketones and / or ethers. After the impregnation process, which is usually completed after about 1 to about 10 hours, the catalysts are dried at temperatures from about 100 to about 150 ° C. and then at temperatures above 500 ° C., preferably above 550 ° C., for about 1 to about 5 hours calcined UIAJ cooled under nitrogen atmosphere.

The carrier can also be pretreated with an inorganic acid, as in GB 1, 216,587. To increase its activity, it can also be used with other metal compounds such as Nb ₂ O ₅ , Ta ₂ O ₅ , Si0 ₂ , B ₂ O ₅ , WO ₅ , MoO ₃ , Ti0 ₂ or Ge0 ₂ , as described in EP 0 639549, be endowed. The carrier can also be thermally pretreated as described in EP 1350779.

If the catalysts are not used immediately after production in the process according to the invention, it is advisable to calcine them again in the manner described above before the reaction.

In principle, the methods known per se to the person skilled in the art are suitable for regenerating the catalyst or catalysts used, for example as described in US Pat. No. 3,365,513, EP-A-933344, US Pat. No. 6,281,402, US Pat. No. 3,725,496, DE-A-32 29419, GB 1144085 , US 3,726,810, BE 746,924, US 4,072,629, DE-A-19 55 640 and DE-A-34276 30.

In addition, the deactivated catalyst can also be regenerated in two stages, for example.

In the 1st stage, the deactivated catalyst is treated with a regeneration gas (regeneration gas 1) at a temperature of 400 to 800 ° C. The regeneration gas 1 is usually a gas which is selected from the group consisting of nitrogen, noble gas or a gas mixture of nitrogen and noble gas which contain up to 10% CO ₂ or up to 40% of a saturated C to C ₈ hydrocarbon can.

After stage 1 is completed, stage 2 of the regeneration begins, in which the deactivated catalyst pretreated with regeneration gas 1 is treated with a gas mixture consisting of an oxygen-containing gas (regeneration gas 2).

The regeneration gas 2 is preferably pure oxygen or a mixture consisting essentially of 0.1 to 100% oxygen, between 50 and 99.9% of a gas selected from the group consisting of nitrogen, inert gas or a gas mixture of nitrogen and Noble gas and possibly up to 10% CO ₂ or up to 40% of a saturated d to C ₈ hydrocarbon.

The regeneration gas 2 is expediently passed at a gas space velocity of 3 to 50 to 500 liters per kg per hour through a catalyst bed from the deactivated catalyst pretreated with regeneration gas. The temperature of the regeneration gas K2 is generally 350 to 850 ° C, preferably 500 to 700 ° C, particularly preferably 550 ° C.

The catalyst is introduced into the tubular reactor in the form of a bed or preferably as a fixed bed catalyst. The reactants are metered in such that the catalyst load is in a range from about 0.2 to about 20 kg / kgh, preferably from about 1 to about 5 kg / kgh.

The pressure in the reactor is selected in a range from about 20 to about 200 bar, preferably from about 30 to about 120 bar and particularly preferably from about 50 to about 80 bar. The reaction temperature is usually about 20 to about 250 ° C., preferably about 20 to about 130 ° C. and very particularly preferably about 30 to about 110 ° C. The reactants are then usually in liquid form.

In order to counteract the usually continuous deactivation of the catalyst, the temperature can optionally be raised continuously or in steps within the ranges mentioned. In this way, the conversion measured at the reactor outlet can be kept largely constant over the course of time. A constant product flow in the work-up section is usually guaranteed.

According to the invention, the discharge stream containing the reaction products is transferred from the reactor into a first distillation apparatus D1, in which the low-boiling Components (A) are separated from the higher-boiling components (B) in a suitable manner. In the context of the present process, lower-boiling constituents (A) of the first distillation stage are primarily to be understood as the excess, unreacted ethylene, which may still contain small amounts of other compounds and which should be separated off as far as possible. Because of the relatively large boiling point difference between the constituents (A) and (B) to be separated, this first distillation stage is advantageously carried out in the form of a flash or distillation. A pressure in the range from approximately 5 to approximately 30 bar, preferably from approximately 5 to approximately 20 bar and a temperature in the range from approximately 10 ° C. to approximately 50 ° C., preferably from approximately 20 to approximately 40 ° C., are advantageously selected. The lower-boiling fraction (A) thus separated off generally contains about 90 to about 99.5% by weight, often about 95 to about 99% by weight, of ethylene. In addition, the lower-boiling fraction (A) generally contains about 0.5 to about 10% by weight, often about 1 to about 5% by weight of unreacted cyclohexene and optionally also small amounts, for example about 0.05 to about 0.5 % By weight 1,7-octadiene. If diluents which are inert under the reaction conditions are used, these can also be removed in whole or in part, depending on their boiling point. In this case, a changed composition of fraction (A) must be taken into account.

The lower-boiling fraction (A) separated in this way can be returned in whole or in part to the reactor R. It is preferably returned as completely as possible, with small amounts being discharged if necessary in order to avoid build-up.

The higher-boiling constituents (B) of the reaction mixture obtained in the first distillation apparatus D1 generally contain about 75 to about 80% by weight, often about 80 to about 90% by weight of unreacted cyclohexene, about 5 to about 20% by weight, preferably about 5 to about 15% by weight of 1,7-octadiene and about 1 to about 10% by weight of ethylene. In addition, it also contains the methathesis usually in small amounts, eg. B through subsequent reactions, high-boiling by-products and the generally predominant part of the inert diluents that may be used. The composition given above relates to a mixture obtained without the use of diluents.

According to the invention, the higher-boiling fraction (B) is transferred to a further distillation apparatus D2. There the lower-boiling constituents (C), hereinafter also referred to as the middle boiler fraction, consisting essentially of unreacted cyclohexene, inert solvent optionally used for diluting the reaction mixture and ethylene which has not yet been separated off in the first distillation step, from the higher-boiling fraction (D) Cut. Distillation columns known per se to the person skilled in the art are suitable for this purpose. Advantageous the separation is carried out at normal pressure or slightly elevated pressure, for example in a range from about 1 to about 10 bar and with a number of separation stages from about 10 to about 50. The reflux ratio is advantageously chosen between 1, 5 and 6.

The medium boiler fraction (C) separated off at the top can likewise be returned completely or partially, if appropriate after complete or partial removal of the inert diluent, to the reactor R. It is preferably returned as completely as possible, with only small amounts generally being discharged in order to avoid build-up.

The higher boiling fraction (D) remaining in the bottom of the distillation apparatus D2 generally consists to a large extent, i.e. usually over 95% by weight of 1,7-octadiene in addition to residues of cyclohexene (normally in the range from about 0.05 to about 0.5% by weight) and the high-boiling by-products already mentioned.

The higher-boiling fraction (D) obtained in this way can be transferred according to the invention into a further distillation apparatus D3 and a lower-boiling product fraction (P) and a high-boiling by-product fraction (N) can be separated. Da-f.u are e.g. Distillation or rectification columns known to those skilled in the art. The separation is usually carried out at normal pressure or, to lower the operating temperature, under reduced pressure. It is advantageous to work under normal pressure with about 10 to 50 separation stages and a reflux ratio of about 1.5 to 6.

In this way it is possible to obtain a product fraction (P) which generally consists of approximately 98 to approximately 99.9% by weight of 1,7-octadiene. Preferably, about 98.5 to about 99.5% by weight of the product fraction (P) consists of 1,7-octadiene.

The by-product fraction (N) which is separated off at the bottom characteristically consists of the high-boiling products of the metathesis reaction, such as, for example, 1,7,13-tetra-decatriene (generally about 60 to 70% by weight), dodecatrienes and to a small extent bi- or tricyclic by-products. It is particularly advantageous from an economic point of view to also return this fraction in whole or in part to the R reactor and thus to the production cycle since, for example, 1,7,13-tetradecatriene can be converted back to 1,7-octadiene by metathesis. To avoid leveling up of the undesired, possibly disruptive by-products, part of the by-product stream (N) is advantageously discharged via an outlet E. The process can be carried out semi or continuously. The economic advantages come into play especially when you run it fully continuously.

5 In a preferred embodiment of the method according to the invention, an apparatus as shown schematically in FIG. 1 is operated in a continuous manner. Accordingly, the reactants ethylene and cyclohexene are introduced in a molar ratio of about 1: 1 to about 6: 1 without further dilution into a tubular reactor R and there with a fixed bed catalyst consisting of 10% by weight of Re ₂ O ₇ to 0 Al ₂ O ₃ brought into contact in the form of 1.5 mm long strands. The temperature in the reactor R is selected such that it is in the range from about 25 to about 130 ° C., preferably from about 30 to about 100 ° C. The pressure in the reactor R is advantageously about 30 to about 120 bar, preferably about 30 to about 80 bar. 5 The product stream is then transferred to a flash distillation apparatus D1 and separated into a low-boiling fraction (A) and a higher-boiling fraction (B) at a pressure of about 5 to about 20 bar and a temperature in the range from about 20 to about 40 ° C. 0 The low-boiling fraction (A) is returned as completely as possible to the educt stream and thus to the reactor R, only small amounts being discharged in order to avoid build-up.

The higher-boiling, about 80 to about 90% by weight of unreacted cyclohexene, about 57 to about 15% by weight of 1,7-octadiene and also about 1 to about 10% by weight of ethylene-containing higher-boiling constituents (B) of the reaction mixture are then transferred in distillation cabinet D2. There, the medium boiler fraction (C), which essentially consists of unreacted cyclohexene and not yet separated ethylene, is separated from the higher-boiling fraction (D). The separation is advantageously carried out at normal pressure or slightly elevated pressure, for example in a range from about 1 to about 10 bar and with a number of separation stages from about 10 to about 50. The reflux ratio is advantageously chosen between 1.5 and 6.

The medium boiler fraction (C), which is separated off at the top, is recycled as completely as possible5 into the educt stream and thus back into the reactor R. As a rule, only small amounts are discharged to avoid build-up.

The fraction (D) remaining in the bottom of the distillation column D2 and generally consisting of more than 95% by weight of 1.7 octadiene in addition to residues of cyclohexene (normally in the range O from about 0.05 to about 0.5% by weight) is transferred if a higher purity is desired, into a distillation or rectification column D3, where the lower-boiling product fraction (P) is separated from the high-boiling secondary Product fraction (N). The separation is usually carried out at normal pressure or, to lower the operating temperature, under reduced pressure. A reflux ratio of about 1.5 to 6 is advantageously set under normal pressure at about 10 to 50 separation stages.

The by-product fraction (N) which is separated off at the bottom of column D3 is likewise returned, in whole or in part, to reactor R and thus back to the production cycle. To avoid leveling up of the undesired, possibly disruptive by-products, part of the by-product stream (N) is advantageously discharged via an outlet E.

In this way it is possible to be very pure, i.e. to produce about 98.5 to about 99.9% 1, 7-octadiene on an industrial scale and in an economically attractive manner. The recyclable material obtained in this way is suitable as a starting substance or as an intermediate product for a large number of syntheses of even more highly refined products. In particular, it is suitable for the production of all kinds of fine chemicals, e.g. for the production of active ingredients or additives for pharmaceutical preparations or pharmaceuticals, all kinds of cosmetics or foodstuffs or luxury foods, the 1, 7-octadiene thus produced is particularly suitable for the production v = i, ι decandial by double hydroformylation of both terminal double bonds. Decandial can include serve as a starting material for the synthesis of a variety of macrocyclic ketones, e.g. Muscon, which represent popular smell or aroma substances.

Various systems known to those skilled in the art can be used to prepare the dialdehydes by hydroformylation, such as Rh / organophosphorus systems or Rh / organopolyphosphorus systems (Appl. Homogeneous Catalysis with Organometallic Compounds, B. Cornils, W.A. Hermann, VCH, 1996). Preferred to achieve high linearities in the Rh-catalyzed hydroformylation are as cocatalysts e.g. Phosphines, organopolyphosphorus compounds such as e.g. Chelate phosphines, chelate phosphites or chelate phosphoramidites. Examples include Rh / triphenylphosphine systems (e.g. Falbe, New Synthesis with Carbon Monoxide, Springer-Verlag 1980), Rh / chelate phosphine systems (e.g. WO 01/58589), Rh / chelate biphosphites (e.g. WO 97/20801 ) or Rh / chelate phosphoramidites (for example WO 03/018192, WO 02/83695 and WO 04/026803). WO 04/26803 describes a process for the preparation of dialdehydes and / or ethylenically unsaturated monoaldehydes by hydroformylation of ethylenically unsaturated compounds.

Suitable hydroformylation catalysts in the process according to the invention are, for example, rhodium complexes with phosphorus ligands of the general formula I

in the Q a bridge group of the formula

is

wherein

A ^' "and A ² independently of one another represent O, S, SiR ^a R ^b , NR ° or CR jd ^α DRβ ^e , where

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

R and R ^β independently of one another represent hydrogen, alkyl, cycloalkyl, heterocycloalkyl, aryl or hetaryl or together with the carbon atom to which they are attached form a cycloalkylidene group having 4 to 12 carbon atoms or the group R ^d together with a further group R ^d or the group R ^e together with another group R ^{β form} an intramolecular bridge group D, D is a double-bonded bridge group selected from the groups

is where

R ⁹ and R ¹⁰ independently of one another represent hydrogen, alkyl, cycloalkyl, aryl, halogen, trifluoromethyl, carboxyl, carboxylate or cyano or are connected to one another to form a C ₃ -C ₄ -alkylene bridge, 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-, acyl or nitro,

c is 0 or 1,

Y represents a chemical bond,

R ⁵ , R ⁶ , R ⁷ and R ⁸ independently of one another are hydrogen, alkyl, cycloalkyl, heterocycloalkyl, aryl, hetaryl, COOR ^f , COO ^" M ⁺ , SO ₃ R ^f , SO ^~ ₃ M ⁺ , NE ¹ E ² , NE ¹ E ² E ³⁺ X ^~ , alkylene-NE ¹ E ² E ³⁺ X-, OR ^f , SR ^f , (CHR ^g CH ₂ O) _x R ^f , (CH ₂ N (E ¹ )) _x R ^f , (CH ₂ CH ₂ N (E ¹ )) _x R ^f , halogen, trifluoromethyl, nitro, acyl or cyano,

wherein

R ^f , E ¹ , E ² and E ³ 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

x represents an integer from 1 to 120, or

R ⁵ and / or R ⁷ together with two adjacent carbon atoms of the benzene nucleus to which they are attached represent a condensed ring system with 1, 2 or 3 further rings,

a and b independently of one another denote the number 0 or 1

P for phosphorus

and

R ¹ , R ² , R ³ , R ⁴ independently of one another represent hetaryl, hetaryloxy, alkyl, alkoxy, aryl, aryloxy, cycloalkyl, cycloalkoxy, heterocycloalkyl, heterocycloalkoxy or an ME ¹ E ² group, with the proviso that R ¹ and R ³ are pyrrole groups bonded to the phosphorus P via the nitrogen atom, or wherein R ¹ together with R ² and / or R ³ together with R ^{4 is} a double-bonded group E which contains at least one pyrrole group bonded to the phosphorus atom P via the pyrrolic nitrogen atom formula Py-IW

form what

Py is a pyrrole group

I stands for a chemical bond or for O, S, SiR ^a R ^b , NR ^C or CR ^,

W represents cycloalkyl, cycloalkoxy, aryl, aryloxy, hetaryl or hetaryloxy,

and

R ^h and R 'independently of one another represent hydrogen, alkyl, cycloalkyl, heterocycloalkyl, aryl or hetaryl,

or a bispyrrole group of the formula Py-I-Py bonded to the phosphorus atom P via the nitrogen atoms

form.

Preferred phosphoramidite ligands are those of the formula la

wherein R ⁵ , R ¹⁶ , R ¹⁷ and R ^{18 are} independently hydrogen, alkyl, cycloalkyl. Heterocycloalkyl, aryl, hetaryl, W'COOR ^k , W'COO ^' M ⁺ , W' (S0 ₃ ) R ^k , W '(S0 ₃ ) -M ⁺ , W'P0 ₃ (R ^k ) (R'), W '(P0 ₃ ) ₂ - (M ⁺ ) ₂ , W'NE E ⁵ , W' (NE ⁴ E ⁵ E ⁶ ) ⁺ χ-, W'OR ^k , W'SR ^k , (CHR'CH ₂ 0 ) _y R ^k , (CH ₂ NE ⁴ ) _y R ^k , (CH ₂ CH ₂ NE ⁴ ) _y R ^k , halogen, trifluoromethyl, nitro, acyl or cyano, in which

W 'represents a single bond, a hetero atom or a divalent bridging group with 1 to 20 bridge atoms, E ⁴ , E ⁵ , E ⁶ each represent the same or different radicals selected from hydrogen, alkyl, cycloalkyl or aryl,

R ^{1 represents} hydrogen, methyl or ethyl,

M ^{+ stands} for a cation equivalent, stands for an anion equivalent and stands for an integer from 1 to 240,

where in each case two adjacent radicals R ¹⁵ , R ¹⁸ , R ¹⁷ and R ¹⁸ together with the carbon atoms of the pyrrblr ring to which they are attached can also represent a condensed ring system with 1, 2 or 3 further rings,

with the proviso that at least one of the radicals R ¹⁵ , R ¹⁸ , R ¹⁷ or R ¹⁸ does not represent hydrogen and that R ¹⁹ and R ^{20 are} not linked to one another, l

R ¹⁹ and R ²⁰ independently of one another for cycloalkyl, heterocylocalkyl, aryl or; Stand hetaryl,

a and b independently of one another denote the number 0 or 1

P represents a phosphorus atom,

Q is a bridge group of the formula

is

wherein

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

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

R ^d and R ^θ independently of one another represent hydrogen, alkyl, cycloalkyl, heterocycloalkyl, aryl or hetaryl or together with the carbon atom to which they are attached form a cycloalkylidene group with 4 to 12 carbon atoms or the group R ^d together with another group R ^d or the group R ^β together with another group R ^{β form} an intramolecular bridge group D,

D a two-gang bridge group selected from the groups

is where

R ⁹ and R ¹⁰ independently of one another represent hydrogen, alkyl, cycloalkyl, aryl, halogen, trifluoromethyl, carboxyl, carboxylate or cyano or are connected to one another to form a C ₃ - to C ₄ -A * ^ ylene bridge,

R ¹¹ , R ¹² , R ¹³ and R ¹⁴ independently of one another for hydrogen, alkyl, cycloalkyl, aryl, halogen, trifluoromethyl, COOH, carboxylate, cyano, alkoxy, S0 ₃ H, sulfonate, NE ¹ E ² , alkylene-NE ¹ E ² E ³⁺ χ-, acyl or nitro, c is 0 or 1,

R ⁵ , R ⁶ , R ⁷ and R ⁸ independently of one another are hydrogen, alkyl, cycloalkyl, heterocycloalkyl, aryl, hetaryl, COOR ^f , COO ^" M ⁺ , S0 ₃ R ^f , SO ^" ₃ M ⁺ , NE ¹ E ² , NE E ² E ³⁺ X ^" , alkylene-NE E ² E ³⁺ X-, OR ^f , SR ^f , (CHR ^g CH ₂ 0) _x R ^f , (CH ₂ N (E ¹ )) _x R ^f , (CH ₂ CH ₂ N (E ¹ )) _x R ^f , halogen, trifluoromethyl, nitro, acyl or cyano, where R ^f , E ¹ , E ² and E ³ each have the same or different radicals selected from hydrogen, alkyl, Mean cycloalkyl or aryl,

R ^{9 represents} hydrogen, methyl or ethyl, M ^{+ represents} a cation,

X ^"stands for an anion and x stands for an integer from 1 to 120, or R ⁵ and / or R ⁷ together with two adjacent carbon atoms of the benzene nucleus to which they are attached represent a condensed ring system with 1, 2 or 3 further rings.

Such ligands are the subject of WO 02/083695, to which reference is hereby made in full and where the preparation of these ligands is also described. Preferred ligands from this class are e.g. the following compounds, this list is for illustrative purposes only and is not restrictive with regard to the ligands which can be used.

10

25

Et: Ethyl Me: Methyl

Other suitable phosphori ligands are diphosphines and diphosphinites as described, for example, in WO 01/58589. The following diphosphines or diphosphinites are mentioned as examples:

58 59 60

Oct: octyl

61 62 63

64

In addition, ligands as described in WO 95/30680 are suitable in the process according to the invention, for example:

65 66

Other suitable phosphoramidite ligands for hydroformylation with rhodium complex catalysts are also the phosphoramidite ligands according to WO 98/19985 and WO 99/52632, with 2,2'-dihydroxy-1,1'-biphenylene or 2,2 ^, -dihydroxy-1,1 ' -binaphthylene bridging groups which carry heteroaryl groups linked to the phosphorus atom via the nitrogen atom, such as pyrrolyl or indolyl groups, for example the ligands:

10

The 1,1'-biphenylene or 1,1'-binaphthylene bridging groups of these ligands can also be linked via the 1,1-position by a methylene (CH ₂ -), a 1,1-ethylene (CH ₃ -CH < ) or a 1,1-propylene group (CH ₃ -CH ₂ -HC <).

Suitable phosphinite ligands for hydroformylation with rhodium complex catalysts include also the ligands described in WO 98/19985, for example

Also suitable as ligands for the hydroformylation with rhodium complex catalysts are phosphite and phosphonite ligands, as are described, for example, in WO 01/58589. The following ligands may be mentioned by way of example only:

Also suitable as ligands for the hydroformylation with rhodium complex catalysts are phosphine ligands with the xanthenyl-bis-phosphoxanthenyl skeleton, as described, for example, in WO 02/068371 and EP-A 982314. Some of these ligands are listed below by way of illustration only: ..

Suitable chelate phosphite ligands for the hydroformylation with rhodium complex catalysts of these ligands are e.g. those of the general formulas II, III and IV

in which G is a substituted or unsubstituted divalent organic bridging group with 2 to 40 carbon atoms, M represents a divalent bridging group selected from -C (R ^W ) ₂ -, -O-, -S-, NR ^V , Si (R ^l ) ₂ - and -CO-, where the groups R ^{v are the} same or different and represent hydrogen, an alkyl group having 1 to 12 carbon atoms, a phenyl, tolyl and anisyl groups, the groups R ^{v are} hydrogen or a substituted or is an unsubstituted hydrocarbon group having 1 to 12 carbon atoms, the groups R ^{1 are} identical or different and represent hydrogen or the methyl group, m is the number 0 or 1, the groups are identical or different and represent an unsubstituted or substituted aryl group, the Index k has a value of 0 or 1 h, the groups R ^{x are} identical or different and represent unsubstituted or substituted monovalent alkyl or aryl groups and R ^{γ is} a divalent organic radical , selected from unsubstituted or substituted alkylene, arylene, arylene-alkylene-arylene and bis-arylene groups. The following chelphosphite ligands which can be used in the process according to the invention may be mentioned by way of example only, for the purpose of illustration but not by way of limitation:

Such and other bisphosphite chelate ligands are the subject of EP-A 213369 and US-A 4769 498 and their preparation is described there.

Instead of the bisphosphite chelate ligands mentioned above, monodentate monophosphite ligands of the general formula VP (OR ^s ) (OR ^τ ) (OR ^u ) V

can be used to complex the rhodium hydroformylation catalyst and as a free ligand. The suitability of such ligands and their complexes with rhodium as catalysts for the hydroformylation is known. In the monophosphite ligands of the general formula V, the radicals R ^s , R ^τ and R ^u independently of one another represent identical or different organic groups with generally 1 to 30, preferably 5 to 30 carbon atoms, for example substituted or unsubstituted alkyl, aryl, , Arylalkyl, cycloalkyl and / or heteroaryl groups. Because of their increased hydrolysis and degradation stability, sterically hindered monophosphite ligands such as are described, for example, in EP-A 155 508 are preferred for this purpose. The following monophosphite ligand structures are mentioned by way of example only for the purpose of illustration:

Known ligands for hydroformylation with rhodium complex catalysts are also such bidentate ligands which, in addition to a phosphite group, also carry a phosphinite or phosphine group in the ligand molecule. Such ligands include described in WO 99/50214. Some such ligands are listed below by way of example only:

10

Bu ': tertiary butyl Ph: phenyl

In general, under hydroformylation conditions, catalytically active species of the general formula H _g Z _d (CO) _β G _{f are} formed from the catalysts or catalyst precursors used in each case, in which Z represents a metal of subgroup VIII, G represents a phosphorus or arsenic group. or antimony-containing ligands, for example for one of the phosphorus-containing ligands as described above and d, e, f, g for natural numbers, depending on the valence and type of the metal and the binding force of the ligand G. Preferably, e and f independently of one another have a value of 1, for example 1, 2 or 3. The sum of e and f preferably has a value of 2 to 5. The complexes of metal Z with the ligands used according to the invention can If desired, G additionally contain at least one further ligand not used according to the invention, for example from the class of the triarylphosphines, in particular triphenylphosphine, triarylphosphites, triarylphosphinites, triarylphosphonites, phosphabenzenes, trialkylphosphines or phosphametalocenes. Such complexes of the metal Z with ligands used according to the invention and not used according to the invention form z. B. in an equilibrium reaction tion after adding a ligand to a complex of the general formula H _g Z _a (CO) _s G _f .

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 process according to the invention can also be prepared separately and isolated by customary processes. To prepare the catalysts in situ, at least one compound of the general formula I to V, a compound or a complex of a metal from subgroup VIII, if desired one or more additional ligands and, if appropriate, an activating agent in an inert solvent can be used Implement hydroformylation conditions.

Suitable rhodium compounds or complexes are e.g. B. rhodium (ll) - 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 Rfιodium (III) acid, trisammonium hexachlororhodate (III) etc. Furthermore, siφ ( Rhodium complexes such as rhodium biscarbonylacetylacetonate, acetylacetonatobiseth * & 3nrhodium (l) 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 Ru0 ₄ or KRu0 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 P 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 and cobalt naphthenoate. Here too, the carbonyl complexes of cobalt such as dicobalt octacarbonyl, tetrakobalt dodecacarbonyl and hexacobalt hexadecacarbonyl can be used.

The above-mentioned and other suitable compounds of cobalt, rhodium, ruthenium and iridium are known, commercially available, or their preparation is adequately described in the literature, or they can be prepared by a person skilled in the art analogously to the compounds already known. Suitable metals of subgroup VIII are in particular cobalt and rhodium, and rhodium is particularly preferred.

The aldehydes used in the hydro-. Formylation of the respective olefins arise, as well as 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 Essigester or Texanol ^®, ethers such as tert-butyl methyl ether and tetrahydrofuran. If the ligands are sufficiently hydrophilized, alcohols such as methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, ketones such as acetone and methyl ethyl ketone etc. can also be used. So-called "ionic liquids" can also be used as solvents. These are liquid salts, for example N, N'-dialkylimidazolium salts such as the N-butyl-N'-methylimidazolium salts, tetraalkylammonium salts such as the tetra-n-butylammonium salts, N-alkylpyridinium salts such as the n-butylpyrid'nJum salts , Tetraalβ Iphosphonium salts such as the trishexyl (tetradecyl) phosphonium salt, z. B. the Tetraflü ^ oborate, acetates, tetrachloroaluminates, hexafluorophosphates, chlorides and tosylates.

It is also possible to carry out the reactions in water or aqueous solvent systems which, in addition to water, contain a water-miscible solvent, for example an alcohol such as methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, a ketone such as acetone and methyl ethyl ketone or contain another solvent. For this purpose, ligands of the formula I or II are used which are modified with polar groups, for example ionic groups such as S0 ₃ M, C0 ₂ M with M = Na, K or NhU or like N (CH ₃ ) ₄ ⁺ . The reactions then take the form of two-phase catalysis, the catalyst being in the aqueous phase and feedstocks and products forming the organic phase. The implementation in the "ionic liquids" can also be designed as a two-phase catalysis.

A process is preferred which is characterized in that the hydroformylation catalyst is prepared in situ, using at least one of the ligands as described above, a compound or a complex of a metal from subgroup VIII and, if appropriate, an activating agent in an inert Solvent under the hydroformylation conditions to react. If desired, however, the ligand-metal complexes can also be prepared separately and isolated by customary methods.

The hydroformylation reaction can be carried out continuously, semi-continuously or batchwise. Suitable reactors for the continuous reaction are known to the person skilled in the art and are described, for. B. in Ulimann's Encyclopedia of Industrial Chemistry, Vol. 1, 3rd Edition, 1951, pp. 743 ff.

Suitable pressure-resistant reactors are also known to the person skilled in the art and are described, for. B. in Ulimann's Encyclopedia of Industrial Chemistry, Vol. 1, 3rd Edition, 1951, pp. 769 ff. In general, an autoclave is used in the discontinuous mode of operation for the method according to the invention, which, if desired, can be provided with a stirring device and an inner lining.

The composition of the synthesis gas of carbon monoxide and hydrogen used in the process according to the invention can vary within wide ranges. The molar ratio of carbon monoxide and hydrogen is usually about 5:95 to 70:30, preferably about 40:60 to 60:40.

The temperature in the hydroformylation reaction is generally in a range from about 20 to 180.degree. C., preferably about 40 to 140.degree. C., in particular about 50 to ^5.degree. ^120.degree. C. The reaction is usually carried out at the Partial pressure of the reaction gas is carried out at the selected reaction temperature. The pressure is generally in a range from about 1 to 700 bar, preferably 1 to 600 bar, in particular 1 to 300 bar. The reaction pressure can be varied depending on the activity of the hydroformylation catalyst used. In general, the catalysts based on phosphorus, arsenic or antimony-containing pnicogen chelate compounds allow reaction in a range of low pressures, such as in the range from 1 to 100 bar, preferably 5 to 50 bar.

The molar ratio of the ligand (s) selected to the metal of subgroup VIII in the hydroformylation medium is generally in a range from about 1: 1 to 1000: 1, preferably from 1: 1 to 100: 1, in particular from 1: 1 to 50: 1 and very particularly preferably 1: 1 to 20: 1.

The molar ratio of metal from subgroup VIII to substrate is usually below 1 mol%, preferably below 0.5 mol% and in particular below 0.1 mol% and very particularly preferably below 0.05 mol%.

The hydroformylation catalysts can be separated from the discharge of the hydroformylation reaction by customary processes known to those skilled in the art and can generally be used again for the hydroformylation.

The catalysts described above can also be suitably, e.g. B. by connection via functional groups suitable as anchor groups, adsorption, grafting fung, etc. to a suitable carrier, e.g. B. made of glass, silica gel, synthetic resins, etc., immobilized. They are then also suitable for use as solid-phase catalysts.

One embodiment of the present invention relates to the production of dialdehydes. In a preferred embodiment, the dialdehydes are produced batchwise. Discontinuous hydroformylation processes are known in principle to the person skilled in the art. When the reaction has ended, the reactor is generally first let down. The synthesis gas released and any unreacted unsaturated compounds can be reused in whole or in part, if necessary after working up. The rest of the reactor consists essentially of dialdehyde, high-boiling by-products (hereinafter also referred to as high boilers) and catalyst. For the work-up, the reactor contents can be subjected to a one- or multi-stage separation, at least one fraction being enriched in dialdehyde being obtained. The separation into a fraction enriched in dialdehyde can be carried out in various ways, for example by distillation, crystallization or membrane filtration, preferably by distillation. In a particularly preferred embodiment of the batch process, ηan uses a reactor with a distillation column attached, so that the distillation can be carried out from the reactor. The distillation column is optionally provided with rectification trays in order to achieve the best possible separation performance. The distillation can be carried out at normal pressure or at reduced pressure. The fraction enriched in dialdehyde can be isolated at the top or in the upper region of the column, it being possible to isolate at least one fraction depleted in dialdehyde in the bottom or in the lower region of the column. Suitable columns, temperature and

Printing parameters are known to the person skilled in the art. The fraction enriched in dialdehyde can optionally be subjected to a further purification step. The fraction depleted in dialdehyde essentially contains high boilers and the catalyst. The catalyst can be separated off by customary processes known to the person skilled in the art and can in general - if appropriate after working up - be used again in a further hydroformylation.

In a further preferred embodiment, the dialdehydes are prepared continuously. In the continuous process, an unsaturated compound is subjected to hydroformylation in one or more reaction zones. A discharge is withdrawn from the reaction zone, which is generally first depressurized. This releases unreacted synthesis gas and unsaturated compounds which are generally returned to the reaction zone, if appropriate after working up. The remaining discharge can be separated into a fraction enriched in dialdehyde by means of customary measures known from the prior art, for example by distillation, crystallization or membrane filtration. Suitable distillation plants are known to the person skilled in the art. Of Thin-film evaporators are also suitable. In the separation by distillation, a fraction consisting essentially of high boilers and catalyst is removed from the bottom or from the lower region of the column and can be returned directly to the reaction zone. However, the high boilers are preferably discharged beforehand in whole or in part before recycling and the catalyst is returned to the reaction zone, if appropriate after working up. At least one fraction enriched in dialdehyde, which optionally also contains unsaturated monoaldehyde, is removed from the top or in the upper region of the column. Expediently, the fraction still containing unsaturated monoaldehyde enriched in dialdehyde is subjected to at least one further separation, at least one fraction enriched in unsaturated monoaldehyde and one fraction enriched in dialdehyde being obtained. The phase enriched in unsaturated monoaldehyde is returned to the reaction zone and the phase enriched in dialdehyde is worked up.

In a preferred embodiment, diolefin containing internal double bonds or mixtures of diolefins which contain diolefin with internal double bonds can be reacted. The implementation can be carried out, for example, as follows: e

In the case of diolefins which contain, in addition to terminal internal double bonds, it is advantageous to carry out the reaction under conditions in which the terminal double bonds are preferentially hydroformylated with high n-selectivity and then the internal double bonds under so-called isomerizing hydroformylation conditions to give aldehydes with high n- Share to be implemented. In this way, for example, mixtures of 1,7-octadiene with at least one further diolefin, each with at least one further internal double bond, can be hydroformylated with good success to give the corresponding terminal dialdehyde. An example of this is the reaction of 1, 7-octadiene which is contaminated with 1, 6-octadiene, as can occur, for example, in the context of the metathesis reaction according to the invention described above if appropriate conditions are selected. Such a hydroformylation process is described in the unpublished German patent application with the file number 10349482.0, to which full reference is made. The olefin composition is preferably reacted in the first reaction zone at a total pressure of 10 to 40 bar with synthesis gas of a carbon monoxide: hydrogen moiety ratio of 4: 1 to 1: 2 up to 40 to 95% based on olefins with terminal double bonds the hydroformylation output is reacted in one or more subsequent reaction zones at a total pressure of 5 to 30 bar with synthesis gas of a carbon monoxide: hydrogen molar ratio of 1: 1 to 1: 1000, the total pressure in one or more subsequent reaction zones preferably being lower in each case than in the previous reaction zone. In a discontinuous procedure, this can be achieved by changing the reaction conditions according to the desired conversion of the terminal double bonds.

The present invention also relates to the use of 1,10-decanedial produced in the manner described above for the production of optionally olefinically unsaturated 2,15-hexadecanedione and for the production of 3-methylcyclopenta-decanone (Muscon) and / or its partially hydrogenated analogs by intramolecular aldol reaction of optionally olefinically unsaturated 2,15-hexadecanedione and optionally subsequent hydrogenation.

As is known, it is possible to use 1,7-octadiene prepared in another way for the hydroformylation and synthesis of muscon, for example 1,7-octadiene which is prepared directly from butadiene by dimerization or by detours via octadienols and their derivatives and via cyclooctene through pyrolysis has been. However, these starting materials not produced according to the invention have to be laboriously cleaned in order to avoid var impurities such as e.g. to remove conjugated dienes and oxygen-containing impurities.

2,15-hexadecanedione and its olefinically unsaturated analogues are important intermediates for the synthesis of macrocyclic ketones, in particular for the synthesis of 3-methylcyclopentadecanone (Muscon) of the formula VI, one of the most important musk fragrances.

A good synthetic access to the 2,15-hexadecanedione or its olefinically unsaturated analogues is therefore one of the prerequisites for an economically satisfactory and technically feasible synthesis of the muscle or its analogs.

DE-A 39 18015 describes a process for the production of muscon and open-chain and partially olefinically unsaturated 2,15-diketones as intermediates for this process and the production thereof. Two reaction sequences are disclosed as production methods for the optionally olefinically unsaturated 2,15-hexadecanediones: firstly, 1,10-decanediol is oxidatively dehydrated to 1,10-decanedial and then reacted with a suitable Wittig reagent. Alternatively, 1,6-hexanediol can also be oxidatively dehydrogenated to the corresponding dialdehyde and then with 2 equivalents of a vinyl Grignard reagent to form the 1,9-decadiene Convert 3,8-diol. The desired intermediate is obtained from this by Caroll reaction with an alkyl acetoacetic acid ester.

The optionally olefinically unsaturated 2,15-hexadecanediones are then cyclized by intramolecular aldol condensation in the gas phase and then catalytically hydrogenated to the muscon.

Further access routes to unsaturated 2,15-hexadecanediones as well as to equivalent intermediates and to the muscon can be found in the same document.

JP-A 2000001452 describes a process for the preparation of diketones, i.a. of 2,15-hexadecanedione starting from dialdehydes by base-catalyzed aldol reaction with acetone under hydrogenating conditions.

In addition, M. Baumann et al. In Tetrahedron Lett. 1976, 3585 the production of muscon starting from cyclododecenone by Nazarov cyclization with 3-butinci,> ^{• '} : r ^• A synthesis of muscon starting from tetradecanedioic acid by methylation of the acid chloride to 2,15-hexadecadione and subsequent aldol cyclization and

S. Ellwood and T. Haines in Current Topics in Flavors and describe hydrogenation

Fragrances, 1999, Kluwer Academic Publishers, Amsterdam, 79-95.

R. Baker et al. teach in J. Chem. Soc, Chem. Comm. 1972, 802 the production of Muscon by nickel-catalyzed coupling of butadiene, allen and carbon monoxide and subsequent hydrogenation.

S. Warwel et al. describe in Seifen - Öle - Fette - Wachsen, 1989, 115, 538 - 545 the production of 8-hexadecen-2,15-dione starting from cycloheptene and the subsequent conversion to muscon by aldol condensation and subsequent hydrogenation.

A further object of the present invention was accordingly to provide an alternative process with which 2,15-hexadecanedione or its olefinically unsaturated analogs can be prepared economically and on an industrial scale in a manner which is easy to carry out.

The 1,10-decandial obtained according to the invention is particularly suitable for the preparation of 2, 15-hexadecanedione of the formula VI I and 3, 13-hexadecadiene-2, 15-dione of the formula VIII, the latter in the form of E / Z- Mixtures can exist with regard to the configuration of the CC double bonds. The preferred procedure is that decanedial is reacted with acetone in the presence of a base and optionally catalytically hydrogenated, or decanedial is reacted with acetoacetic ester in the presence of a base, then saponified and decarboxylated and, if appropriate, finally catalytically hydrogenated.

The good manufacturability of these intermediates also makes the process, in combination with known process steps, suitable for the preparation of 3-methylcyclopentadecanone (Muscon) of the formula VI. The integration of the process according to the invention for the preparation of optionally olefinically unsaturated 2,15-hexadecanediones in a synthesis route to Muscon or its olefinically unsaturated analogue thus represents a further aspect of the present invention.

The 1, 1 O-Dekajndial serving as the starting connection is accessible in various ways. The dialdehyde can be, for example, as described in DE-A 39 18015, by oxidative dehydrogenation of 1,10-decanediol, e.g. but also obtained by reducing the 1,10-dicarboxylic acid. A preferred production method in the process according to the invention is the double hydroformylation of 1, 7-octadiene or mixtures of 1,6- and 1,7-octadiene, preferably of 1,7-octadiene, on rhodium catalysts, which is to be carried out as described above. 1,7-octadiene or the mixtures of 1,6- and 1,7-octadiene can be prepared in a preferred manner by metathesis of cyclohexene in the presence of ethylene.

To prepare 2,15-hexanedecadione or its further conversion to muscon, 1,10-decanedial is reacted either with acetone or with acetoacetic ester in the presence of a base and, if appropriate, subsequently hydrogenated catalytically.

The reaction with acetone is carried out in the presence of a suitable base which catalyzes the aldol condensation, such as, for example, NaOH, KOH, LiOH, Ba (OH) ₂ , Ca (OH) ₂ , CsOH, RbOH and amines, such as, for example, diazabicyclo-1,5- [ 5.4.0] undecane (DBU), piperidine or triethylamine or also basic aluminum oxide (Al ₂ 0 ₃ ). The reaction can be carried out continuously, semi- or batchwise in a homogeneous or heterogeneous phase. As a rule, about 2 to about 30 mol, preferably about 6 to about 14 mol, of acetone and about 2 to about 60 mol, preferably about 6 to about 30 mol, of the catalytically active base are used per mol of 1,10-decanedial to be reacted. The reaction can take place under conditions known per se to the person skilled in the art. For example, acetone or a solvent which is inert under the reaction conditions, such as toluene, diethyl ether or tetrahydrofuran, is used as the solvent. The selected base is usually placed in the solvent and the dialdehyde is added. In this way, better selectivities are generally achieved with addition in portions or continuously. At temperatures of around 100 ° C, the reaction is usually complete after a few hours.

The reaction products thus obtained can subsequently be obtained by methods known per se to the person skilled in the art, e.g. Crystallization, chromatography or distillation can be purified. The olefinically unsaturated reaction products can then be catalytically hydrogenated in a likewise known manner. For this purpose, preference is given to those catalysts which are capable of hydrogenating olefinic double bonds in addition to carbonyl groups. Examples include: Palladium-containing catalysts.

In a preferred embodiment, the aldol condensation of 1,10-decanedial with acetone is carried out under hydrogenating conditions, ie in a one-step process. For this purpose, the reactants are converted into a hydrogen-active catalyst under a hydrogen atmosphere '.; Suitable catalysts are, for example, are those in which the hydrogenation component or components on a support, such as Al ₂ 0 _3, Ti0 ₂ or Zr0 _2l preferably Al ₂ O is applied. ₃ Suitable hydrogenation-active components are transition metals such as Ru, Rh, Ir, Pt, Co and Pd, particularly preferably Pd. The hydrogenation-active components mentioned can optionally contain further metals, preferably lanthanides or compounds thereof. The lanthanides Pr, Nd, Eu, Gd, Dy, Ho, Er and Yb are particularly preferred. It is very particularly preferred to use a catalyst which contains Pd doped with Pr as the hydrogenation-active component and is applied to Al ₂ O ₃ as a support.

The aldol condensation under hydrogenating conditions can be carried out batchwise, semi-continuously or fully continuously. Depending on the driving style, the reaction can be carried out in suitable reactors, e.g. in stirred tanks, tubular reactors, flow tubes, loop reactors or stirred tank cascades. The reaction is usually carried out at temperatures from about 10 to about 280 ° C. and at hydrogen pressures from about 1 to about 100 bar. The reaction is usually complete after a few hours. The turnover is often complete after about 2 hours.

To prepare the olefinically unsaturated compounds of the formula VIII which are obtained in the form of E / Z mixtures with respect to the olefinic double bonds, the aldol reaction of decanedial with acetone is carried out under conventional, ie non-hydrogenating, conditions. Basic catalysts are suitable for this hydrogenation-active component or components. In addition, the hydrogen atmosphere is dispensed with.

The compounds of the formulas VII and VIII which are accessible in this way are equally suitable for cyclization by intramolecular aldol condensation, as is described in detail, for example, in DE-A 39 18 015.

Through the described procedure, the muscon, which is sought after as a fragrance, its partially hydrogenated anologa and, in principle, a large number of other macrocyclic ketones are accessible in a simple, economically advantageous manner that can be carried out on an industrial scale.

If the final hydrogenation of the primary aldol condensation product is carried out under asymmetric conditions, e.g. using a chiral-non-racemic, enantioselective catalyst, it is possible to obtain muscon in an optically active form.

The following examples serve to illustrate the present invention, but without restricting it in any way:

Examples:

Example 1: Preparation of 1, 7-octadiene by metathesis

40 g of a catalyst consisting of 10% by weight of Re ₂ O ₇ on Al ₂ O ₃ (4 mm strands) were placed in an autoclave, 40 bar of ethylene were injected and 180 ml of cyclohexene were metered in. The reaction mixture was heated to 40 ° C. and the ethylene pressure was increased to 200 bar. The reaction mixture was then stirred for 24 h. A conversion of 1.3% was obtained with a selectivity for 1, 7-octadiene of 89%. The space-time yield based on the catalyst was 0.002 kg / kgh.

Example 2a: Continuous preparation of 1, 7-octadiene by metathesis

40 g of a catalyst consisting of 10% by weight of Re ₂ O ₇ on Al ₂ O ₃ (1.5 mm strands) were placed in a tubular reactor. 60 g / h of cyclohexene and 80 g / h of ethylene were metered in continuously at 60 ° C. at a pressure of 80 bar. After 15 h, a sample of the reaction product was analyzed by gas chromatography. A conversion of 7.9% gave 97.3% 1, 7-octadiene and 2.0% 1,7,13-tetradecatriene. 122 g of 1,7-ocadiene were isolated by distillation from the reaction product obtained after 30 hours. The space-time yield based on the catalyst was thus 0.1 kg / kgh. Example 2b: Continuous preparation of 1, 7-octadiene by metathesis with temperature increase and starting material recycling

30 g of a catalyst consisting of 10% by weight of Re ₂ O ₇ on Al ₂ O ₃ (1.5 mm strands) mixed with 30 ml of molecular sieve 13X were placed in a tubular reactor. 60 g / h of cyclohexene and 41 g / h of ethylene were metered in continuously at 25 ° C. at a pressure of 80 bar. For this purpose, the ethylene recovered from the product stream in a stripping column and the cyclohexene recovered in a distillation column were replenished with fresh starting materials. After half an hour of reaction at 25 ° C, the temperature in the reactor was raised continuously to 80 ° C at a rate of 1.5 ° C / h. The reaction was then continued at this temperature. With an average conversion of 8.0%, 98.3% 1, 7-octadiene was obtained. A total of 265 g of 1,7-octadiene were isolated over 42 h. The space-time yield related to the catalyst was thus 0.21 kg / kgh.

Example 3: Hydroformylation of 1,7-octadiene (85%) with Rh / Ligand A

Synthesis of ligand A

Ligand A

28.5 g (218 mmol) of 3-methylindole (Skatol) were initially introduced into about 50 ml of dry toluene at room temperature and the solvent was distilled off in vacuo (removal of traces of water). This process was repeated again. The residue was then taken up in 700 ml of dry toluene under argon and cooled to -65 ° C. Then 14.9 g (109 mmol) PCI ₃ and then slowly 40 g (396 mmol) triethylamine were added at -65 ° C. The mixture was warmed to room temperature over 16 hours and then refluxed for 16 hours. Then 19.3 g (58 mmol) of 4,5-dihydroxy-2,7-di-tert-butyl-9,9-dimethylxanthene in 300 ml of dry toluene were added at room temperature and the mixture was heated under reflux for 16 h. The triethylamine hydrochloride formed was filtered off and washed once with toluene. After concentrating the organic phases, the residue was recrystallized twice from hot ethanol Siert. After drying in vacuo, 36.3 g (71% of theory) of a colorless solid were obtained. ³ P NMR (298 K) d: 105 ppm.

5.1 mg of Rh (CO) ₂ acac (acac = acetylacetonate) and 187 mg of ligand A were dissolved in 5 g of toluene each and placed in a 100 ml steel autoclave which had been rendered inert with synthesis gas (CO: H ₂ = 1: 1) and had a gassing stirrer , Then 10 bar synthesis gas (CO: H ₂ = 1: 1) was injected and gassed at 80 ° C. After 1 h the pressure was released. 10 g of 1,7-octadiene (85% strength, in addition to other olefins and diolefins, in particular 1,6-octadiene) were then metered in by means of a syringe. The mixture was then hydroformylated for 6 h at 80 ° C. (100 ppm Rh; ligand A: Rh = 10: 1) and then a sample was analyzed by means of gas chromatography. A conversion of 99% (based on 1, 7-octadiene) gave 90% diales with a linearity of 98% (linearity = 1.10 - decanedial / sum of the diales). Example 4: Preparation of Muscon

4.1 Hydroformylation of 1,7-octadiene

'^ 5 mg Rh (CO) ₂ acac (acac = acetylacetonate) and 181 mg of ligand A (prepared as listed below) were each dissolved in 5 g of toluene. The two solutions were mixed and heated to 60 ° C. 10 bar of a 1: 1 mixture of CO ₂ and H ₂ (“synthesis gas”) were then injected. After 30 minutes, the reaction vessel was depressurized, 10 g of 1,7-octadiene were added, 20 bar synthesis gas was injected and 6 hours at 60 ° C. Hydroformylated at 98% conversion, decanedial was obtained with a dialdehyde selectivity of 84% and a linearity of 98% (linearity. = 1, 10-decanedial / sum of the diales).

4.2 Aldol condensation of decanedial with acetone under hydrogenating conditions 10 g of decanedial and 40 g of acetone were mixed with 1.6 g of a catalyst consisting of 0.5% by weight of Pd and 5% by weight of Pr0 ₂ (in each case based on the finished catalyst) to Al ₂ 0 ₃ (4 mm strands). Then 10 bar of hydrogen were injected, heated to 180 ° C. and a pressure of 40 bar was set. The reaction was terminated after 24 h. The crude product was analyzed by gas chromatography. With complete conversion, 2.8% dodecanone, 20.8% tridecanal-12-one and 69.5% 2,15-hexadecanedione were obtained in addition to 6.9% (in each case GC area%) of other by-products. When 45 g of acetone and 3.2 g of the catalyst were used under otherwise unchanged conditions, 2.6% of dodecanone, 9.3% of tridecanal-12-one and 73.8% of 2,15-hexadecanedione were also obtained in addition to 14.3 with complete conversion % (each GC area%) of other by-products.

4.3 Intramolecular aldol condensation of 2, 15-hexadecanedione A mixture of 3 g of 2,15-hexadecanedione, 10 ml of water and 60 ml of toluene was evaporated in a tubular reactor. In a nitrogen stream (10 l / h), the mixture was passed over 2 h at 370 ° C. over a bed of a catalyst consisting of 2% by weight of K ₂ O (based on the finished catalyst) onto TiO ₂ (4 mm strands) , The reactor discharge was condensed and analyzed by gas chromatography. With a conversion of 60%, 86% (GC area%) of a mixture of dehydromuscon isomers was obtained.

4.4 Hydrogenation of the dehydromuscon isomers

2 g of the mixture of dehydromuscon isomers obtained as described above were placed in 40 ml of cyclohexane and 1 g of a catalyst consisting of 10% by weight of Pd on carbon (Pd / C 10%) was added. 10 bar of hydrogen were injected and the mixture was stirred at 70 ° C. for 1 h. The crude product obtained was analyzed by gas chromatography. With complete conversion, Muscon was obtained in a yield of 98.5% (GC area%).

When using a catalyst consisting of 10% by weight of Pd on Al ₂ 0 ₃ (Pd / Al ₂ 0 ₃ 10%), a conversion of 98% gave Muscon in a yield of 93.1% (GC area% ).

Claims

claims:

1. Process for the preparation of 1, 7-octadiene by metathesis of cyclohexene with ethylene, characterized in that the unreacted starting materials and any higher-boiling by-products obtained are recycled to the reaction mixture in purified form.

2. The method according to claim 1, characterized in that a. Bringing ethylene and cyclohexene into contact in a reactor R with a suitable catalyst, b. the reaction discharge is transferred to a distillation apparatus D1 and the reaction product is separated into a lower-boiling fraction which contains the unreacted ethylene and a higher-boiling fraction, c. the higher-boiling fraction thus obtained is transferred to a further distillation apparatus D2 and burns into a lower-boiling fraction containing the unreacted cyclohexene and a higher-boiling fraction containing 1, 7-octadiene, and d. the.' -.i the distillation apparatus D1 and D2 each separated lower boiling fractions completely or partially in the reactor R.

3. Process according to claims 1 to 2, characterized in that the higher-boiling reaction output from the distillation apparatus D2 is transferred to a further distillation apparatus D3 and 1, 7-octadiene is separated from higher-boiling by-products.

4. Process according to claims 1 to 3, characterized in that the higher-boiling by-products separated off in distillation apparatus D3 are returned completely or partially to the reactor R.

5. The method according to claims 1 to 4, characterized in that it is carried out continuously.

6. Process according to claims 1 to 5, characterized in that cyclohexene is used which is essentially free of cyclohexanol and / or cyclohexanone.

7. The method according to claims 1 to 6, characterized in that the molar ratio of ethylene used to cyclohexene used is 1 to 10.

1 Fig

8. The method according to claims 1 to 7, characterized in that the molar ratio of ethylene used to cyclohexene used is 2 to 4.

9. The method according to claims 1 to 8, characterized in that one uses a Re, W, Mo, Ru, Os, Ta and / or Nb-containing catalyst.

10. The method according to claims 1 to 9, characterized in that a catalyst is used which contains a Re-containing compound applied to Al ₂ 0 ₃ as a carrier.

11. The method according to claims 1 to 10, characterized in that a catalyst is used which, based on the total weight of the finished catalyst, contains 6 to 12% by weight of Re ₂ O _τ applied to Al ₂ 0 ₃ as support.

12. The method according to claims 1 to 11, characterized in that the catalyst is used in the form of a fixed bed catalyst.

^{■ •■ •}

13. The method according to claims 1 to 12, characterized in that the "*. The reaction is carried out in a tubular reactor at a temperature of 30 to 110 ° C.

14. The method according to claim 13, characterized in that the temperature is increased in the course of the reaction.

15. The method according to claims 1 to 13, characterized in that one carries out the reaction in a tubular reactor at a pressure of 30 to 120 bar.

16. The method according to claims 1 to 14, characterized in that the catalyst load is 1 to 5 kg kg ^"1 h ^{" 1} .

17. Process for the preparation of 1, 10-decandial by isomerizing hydroformylation of mixtures containing 1, 7-octadiene and at least one further diolefin, each with at least one internal double bond.

18. A process for the preparation of 1, 10-decandial, characterized in that 1, 7-octadiene is prepared and hydroformylated by a process according to claims 1 to 16.

19. The method according to claim 18, characterized in that 1,7-octadiene is used which contains further diolefins with at least one internal double bond.

20. The method according to claim 19, characterized in that 1, 7-octadiene is used which contains 1, 6-octadiene.

21. The method according to claim 19 or 20, characterized in that hydroformylated under isomerizing conditions.

22. A process for the preparation of muscon and / or its partially hydrogenated analogs, characterized in that decandial is prepared by a process according to claims 1 to 21 and a. reacted with acetone in the presence of a base or a catalyst suitable for aldol reactions and optionally catalytically hydrogenated or reacted with acetoacetic ester in the presence of a base, then saponified, decarboxylated and optionally catalytically hydrogenated and b. the reaction product is cyclized by intramolecular aldol condensation and optionally hydrogenated.

23. The method according to claim 22, characterized in that one carries out the aldol condensation of decanedial with acetone under hydrogenation conditions.