DE10205361A1 - phosphorus compounds - Google Patents

Abstract

The present invention relates to new phosphorus chelate compounds, catalysts which comprise at least one complex of a metal from subgroup VIII with at least one such phosphorus chelate compound as ligands, and to a process for hydroformylation using these catalysts.

Description

The present invention relates to new ones Phosphorus chelate compounds, catalysts containing at least one complex of a metal the VIII. subgroup with at least one Phosphorus chelate compound include as ligands and a method for Hydroformylation using these catalysts.

Hydroformylation or oxo synthesis is an important one industrial process and is used for the production of aldehydes Olefins, carbon monoxide and hydrogen. These aldehydes can optionally with hydrogen in the same operation corresponding oxo alcohols are hydrogenated. The reaction itself is highly exothermic and generally runs under increased pressure and at elevated temperatures in the presence of catalysts. Co, Rh, Ir, Ru, Pd or are used as catalysts Pt compounds or complexes used for activity and / or Selectivity influencing with N- or P-containing ligands can be modified. In the hydroformylation reaction of Olefins with more than two carbon atoms occur due to the possible CO addition to each of the two carbon atoms of a double bond Formation of mixtures of isomeric aldehydes. In addition, it can Use of olefins with at least four carbon atoms also double bond isomerization, d. H. to a Shifting internal double bonds to a terminal position and vice versa.

Due to the much greater technical importance of the α-aldehydes will optimize the hydroformylation catalysts to achieve the highest possible hydroformylation activity with the lowest possible tendency to form not α- striving for double bonds. There is also a need for Hydroformylation catalysts, which also start from internal linear olefins in good yields to α-standing and lead especially n-permanent aldehydes. Here, the catalyst both the establishment of a balance between internal and terminal double bond isomers as selectively as possible Enable 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, butenes or C ₄ -hydrocarbon mixtures containing butenes and butanes can be subjected to 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 places the entire process at an economic disadvantage.

If technical mixtures, for example C ₄ cuts, are used for the hydroformylation, which are available in large quantities both from FCC plants and from steam crackers and which essentially consist of a mixture of 1-butene and 2-butene and generally butane, the hydroformylation catalyst used must enable the hydroformylation of terminal olefins (1-butene) as selectively as possible and / or be capable of shifting internal double bonds to a terminal position. There is also generally great industrial interest in the provision of such hydroformylation catalysts.

It is known in low pressure rhodium hydroformylation phosphorus-containing ligands for stabilization and / or activation of the catalyst metal. Suitable phosphorus-containing Ligands are e.g. B. phosphines, phosphinites, phosphonites, phosphites, Phosphoramidites, phospholes and phosphabenzenes. The currently on The most common ligands are triarylphosphines, such as. B. Triphenylphosphine and sulfonated triphenylphosphine as these sufficient stability under the reaction conditions have. A disadvantage of these ligands, however, is that in Generally only very high excess ligands are satisfactory Deliver yields in particular of linear aldehydes.

The US 3,816,452 describes the production differently substituted pyrrolyl monophosphines and their use as Flame retardants.

A.M. Trzeciak et al. describe in J. Organomet. Chem. 552, Pp. 159-164 (1998) unbridged Trispyrrolylphosphine-rhodium complexes as catalysts for the hydrogenation of olefins and arenes.

A.M. Trzeciak et al. describe in J. Chem. Soc., Dalton Trans. 1997, pp. 1831-1837 rhodium complexes with unbridged N-pyrrolylphosphines as ligands and the use of these complexes as Hydroformylation.

A.M. Trzeciak et al. describe in C. R. Acad. Sci., Série IIc, S. 235-239 (1999) the hydroformylation of vinylsilanes with Trispyrrolylphosphine-modified rhodium catalysts.

WO-A-00/56451 relates, among other things, to the phosphorus atom Pyrrole derivatives substituted, cyclic oxaphosphorines and Use of these as ligands in catalysts for Hydroformylation.

WO-A-99/52632 relates to a process for hydrocyanation using phosphorus-containing chelate ligands with 1,1'-bisphenylene or 1,1'-bisnaphthylene backbone, in which the phosphorus atom with unsubstituted pyrrole, indole or imidazole groups can be that through a ring nitrogen atom to the phosphorus atom are bound.

No. 5,710,344 describes ligands containing phosphorus atoms 1,1'-biphenylene or 1,1'-binaphthylene backbone with unsubstituted pyrrole, imidazole or indole groups can, which via a ring nitrogen atom to the phosphorus atom are bound. These ligands are suitable for Hydroformylation catalysts based on metals of subgroup VIII.

J. Shen et al. describe in Organometallics 1998, 17, P. 3000-3005 calorimetric studies Diphosphine chelate ligands, including hydrazide-bridged diphenylphosphines and alkylene-bridged dipyrrole phosphines can be used.

Y. Gimbert et al. describe in J. Org. Chem. 1999, 64, S. 3492-3497 Synthesis and properties of Co (0) complexes with Diphosphinoamin ligands. This ligand is including N-bridged bispyrrole phosphines.

H. Brunner and H. Weber describe in Chem. Ber. 118 S. 3380-3395 (1985) optically active aminophosphines and their Use in enantioselective hydrosilylation. These ligands are caused by condensation of 2-pyrrolecarbaldehyde or 2-acetylpyrrole with 1-phenylethylamine and optionally further Subsequent reactions are produced and can be pyrrole nitrogen-phosphonated Have groups.

WO 01/58589 describes compounds of phosphorus, arsenic and of antimony, based on diaryl-fused Bicyclo [2.2.2] basic bodies and catalysts, these as Contain ligands. The atom of the 5th main group can in principle, also hetaryl residues are bound.

DE-A-100 23 471 describes a method for Hydroformylation using a hydroformylation catalyst which comprises at least one phosphine ligand, the two Has triarylphophin groups, each having an aryl radical of the two Triarylphosphine groups via a single bond to one non-aromatic 5- to 8-membered carbocyclic or heterocyclic bridging group is bound. The phosphorus atoms as further substituents, including hetaryl groups exhibit.

The unpublished German patent application P 100 46 026.7 describes a hydroformylation process in which Catalyst a complex based on a phosphorus, arsenic or Antimony-containing compound used as ligand, this Connect two each a P, As or Sb atom and at least two further groups having heteroatoms bonded to one Has xanthene-like molecular structure.

K.G. Moloy et al. describe in J. Am. Chem. Soc. 117 S. 7696-7710 (1995) unsubstituted or not fused and dinuclear pyrrolyl compounds and their Rh and Mo complexes.

D.C. Smith et al. describe in Organometallics 19, Pp. 1427-1433 (2000) platinum complexes by To (dipyrrolylphosphino) alkanes.

EP-A-0 754 715 describes a catalyst composition comprising a metal of subgroup VIII and a Alkylene-bridged di (pyrrolyl-phenyl-phosphine) and their use for Manufacture of polyketones.

WO-A-96/01831 describes chiral diphosphines biheterocyclic compounds of aromatic, 5-atom heterocycles and their use in chiral catalysts for stereoselective Reactions. The heterocyclic nuclei have one Single bond between two ring carbon atoms connected.

WO-A-99/52915 describes chiral ligands containing phosphorus atoms based on bicyclic compounds of carbocyclic and heterocyclic 5- to 6-atom compounds. Here are the the aromatic ring forming the bicyclic via a Single bond between two ring carbon atoms linked together.

None of the above documents describe Phosphorus chelate compounds in which there are three on each of the phosphorus atoms Nitrogen atoms are covalently bound, which are themselves part of a aromatic ring system.

The present invention is based on the object, new To provide phosphorus chelate compounds that prove to be Ligands for transition metal complexes of metals of VIII. Subgroup are suitable for new catalysts based on this To provide metal complexes. Preferably should these ligands can be easily prepared and / or their complexes under the reaction conditions of the reactions to be catalyzed be as stable as possible and have good catalytic activity exhibit. The aim is to hydroformylate α-olefins preferably the highest possible proportion of α-aldehydes, or Alcohols (α selectivity) can be achieved. In particular should Catalysts based on these ligands for hydroformylation internal linear olefins with high regioselectivity in favor terminal product aldehydes are suitable.

Accordingly, phosphorus chelate compounds of the general formula I


found what
B ¹ , B ² , B ³ , B ⁴ , B ⁵ and B ⁶ independently of one another represent a heteroaromatic group which has at least one aromatic ring with a ring nitrogen atom bonded to the phosphorus atom, and
Y stands for a chemical bond or a divalent bridging group with 1 to 20 bridge atoms in the chain between the flanking bonds.

In the context of the present invention, the expression alkyl includes straight-chain and branched alkyl groups. These are preferably straight-chain or branched C ₁ -C ₂₀ alkyl, preferably C ₁ -C ₁₂ alkyl, particularly preferably C ₁ -C ₈ alkyl and very particularly preferably C ₁ -C 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, octyl, nonyl, decyl.

The term alkyl also includes substituted alkyl groups. Substituted alkyl radicals preferably have 1, 2, 3, 4 or 5, particularly preferably 1, 2 or 3 and in particular 1 substituent, selected from cycloalkyl, aryl, hetaryl, halogen, NE ¹ E ² , (NE ¹ E ² E ³ ) ⁺ , Carboxyl, carboxylate, -SO ₃ H and sulfonate.

The term alkylene stands for straight-chain and branched Alkanediyl groups, preferably having 1 to 4 carbon atoms.

The term cycloalkyl includes unsubstituted and substituted cycloalkyl groups. The cycloalkyl group is preferably a C ₅ -C ₇ cycloalkyl group, such as cyclopentyl, cyclohexyl or cycloheptyl.

When the cycloalkyl group is substituted, it has preferably 1, 2, 3, 4 or 5, in particular 1, 2 or 3 substituents, selected from alkyl, alkoxy or halogen.

The term heterocycloalkyl for the purposes 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 the may optionally be substituted, but in the case of substitution, these heterocycloaliphatic groups 1, 2 or 3, preferably 1 or 2, particularly preferably 1, selected from alkyl, aryl, COOR ^a , COO-M ⁺ and NE ¹ E ² , preferred Alkyl, can wear. Examples of such heterocycloaliphatic groups are pyrrolidinyl, piperidinyl, 2,2,6,6-tetramethyl-piperidinyl, imidazolidinyl, pyrazolidinyl, oxazolidinyl, morpholidinyl, thiazolidinyl, isothiazolidinyl, isoxazolidinyl, piperazinyl-, tetrahydrothiophenyl, tetrahydroflanyl, tetrahydroflanyl, tetrahydroflanyl, tetrahydroflanyl, tetrahydroflanyl, tetrahydroflanyl, tetrahydroflanyl, tetrahydroflanyl, tetrahydroflanyl, tetrahydroflanyl, tetrahydroflanyl, tetrahydroflanyl, tetrahydroflanyl, tetrahydroflanyl, tetrahydroflanyl, tetrahydroflanyl, tetrahydroflanyl, and tetrahydroflanyl, called tetrahydroflanyl, tetrahydroflanyl, and tetrahydrothiophenyl, tetrahydroflanyl.

Aryl includes unsubstituted and substituted aryl groups and preferably represents phenyl, tolyl, xylyl, mesityl, naphthyl, Fluorenyl, anthracenyl, phenanthrenyl, naphthacenyl and especially for phenyl or naphthyl.

Substituted aryl radicals preferably have 1, 2, 3, 4 or 5, in particular 1, 2 or 3, substituents selected from alkyl, alkoxy, carboxyl, carboxylate, trifluoromethyl, -SO ₃ H, sulfonate, NE ¹ E ² , alkylene-NE ¹ E ² , nitro, cyano or halogen.

Hetaryl includes unsubstituted and substituted heteroaromatic groups and preferably represents pyridyl, quinolinyl, Acridinyl, pyridazinyl, pyrimidinyl or pyrazinyl, and the following subgroup of the "pyrrole group".

Substituted hetaryl radicals preferably have 1, 2 or 3 substituents selected from alkyl, alkoxy, carboxyl, carboxylate, -SO ₃ H, sulfonate, NE ¹ E ² , alkylene-NE ¹ E ² , trifluoromethyl or halogen.

For the purposes of the present invention, the term “pyrrole group” stands for a series of unsubstituted or substituted, heterocycloaromatic groups which are structurally derived from the pyrrole backbone and contain a pyrrolic nitrogen atom in the heterocycle which can be covalently linked to other atoms, for example a phosphorus atom. 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, can wear.

The above statements on alkyl, cycloalkyl and aryl radicals apply accordingly to alkoxy, cycloalkyloxy and aryloxy radicals.

The term "acyl" in the sense of the present invention stands for Alkanoyl or aroyl groups with generally 2 to 11, preferably 2 to 8 carbon atoms, for example for the acetyl, Propionyl, butyryl, pentanoyl, hexanoyl, heptanoyl, 2-ethylhexanoyl, 2-propylheptanoyl, benzoyl or naphthoyl group.

The residues NE ¹ E ² and NE ⁴ E ⁵ preferably represent N, N-dimethylamino, N, N-diethylamino, N, N-dipropylamino, N, N-diisopropylamino, N, N-di-n-butylamino, N, N-di-tert-butylamino, N, N-dicyclohexylamino or N, N-diphenylamino.

Halogen stands for fluorine, chlorine, bromine and iodine, preferably for Fluorine, chlorine and bromine.

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 C ₁ -C ₄ alkanols, such as methanol, ethanol, n-propanol, isopropanol, n-butanol, sec-butanol and tert-butanol.

M ⁺ stands for a cation equivalent, ie for a monovalent cation or the portion of a multivalent cation corresponding to a positive single charge. M ⁺ is preferably an alkali metal cation, such as. B. Li ⁺ , Na ⁺ or K ⁺ or for an alkaline earth metal cation, for NH ⁴⁺ or a quaternary ammonium compound, as can be obtained by protonation or quaternization of amines. Alkali metal cations are preferred, in particular sodium or potassium ions.

X ^- stands for an anion equivalent, ie for a monovalent anion or the proportion of a multivalent anion corresponding to a negative single charge. X ^- preferably represents a carbonate, carboxylate or halide, particularly preferably Cl ^- and Br ^- .

The values for x represent an integer from 1 to 240, preferably for an integer from 3 to 120.

Condensed ring systems can be linked by annealing (condensed) aromatic, hydroaromatic and cyclic Connections. Condensed ring systems consist of two, three or more than three rings. Depending on the type of link a distinction is made in condensed ring systems between an ortho- Annulation, d. H. each ring has with each neighboring ring one edge, or two atoms together, and one peri annulation in which a carbon atom belongs to more than two rings. Are preferred among the condensed ring systems ortho-condensed ring systems.

The heteroaromatic groups B ¹ , B ² , B ³ , B ⁴ , B ⁵ and B ^{6 are} preferably pyrrole groups bonded to the phosphorus atom via a ring nitrogen atom. The meaning of the pyrrole groups corresponds to the definition given at the beginning.

B ¹ , B ² , B ³ and B ⁴ are preferably selected independently of one another from groups of the general formula II


wherein
R ¹ , R ² , R ³ and R ⁴ independently of one another are hydrogen, alkyl, cycloalkyl, heterocycloalkyl, aryl, hetaryl, WCOOR ^a , WCOO ^- M ⁺ , W (SO ₃ ) R ^a , W (SO ₃ ) ^- M ⁺ , WPO ₃ E ¹ E ² , W (PO ₃ ) ^2- (M ⁺ ) ₂ , WNE ¹ E ² , W (NE ¹ E ² E ³ ) ⁺ X ^- , WOR ^a , WSR ^a , (CHR ^b CH ₂ O) _x R ^a , (CH ₂ NE ¹ ) _x R ^a , (CH ₂ CH ₂ NE ¹ ) _x R ^a , halogen, trifluoromethyl, nitro, acyl or cyano,
wherein
W represents a single bond or a divalent bridging group with 1 to 20 bridge atoms,
R ^a , E ¹ , E ² , E ³ each represent the same or different radicals selected from hydrogen, alkyl, cycloalkyl or aryl,
R ^{b represents} hydrogen, methyl or ethyl,
M ^{+ stands} for a cation equivalent,
X ^{- stands} for an anion equivalent and
x represents an integer from 1 to 240,
where two adjacent radicals R ¹ and R ² and / or R ³ and R ⁴ 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.

According to the invention, the compounds of formula II pyrrolic nitrogen atom to a phosphorus atom of the Phosphorus chelate compounds bound.

In the compounds of the formula II, one or two of the radicals R ¹ , R ² , R ³ and R ⁴ are preferably one of the abovementioned substituents other than hydrogen and the rest are hydrogen. Compounds of the formula II are preferred which carry a substituent other than hydrogen in the 2-position, 2,5-position or 3,4-position.

The substituents R ¹ to R ⁴ which are different from hydrogen are preferably selected independently of one another from C ₁ -C ₈ -, preferably C ₁ -C ₄ -alkyl, especially methyl, ethyl, isopropyl and tert-butyl, alkoxycarbonyl, such as methoxycarbonyl, ethoxycarbonyl , Isopropyloxycarbonyl and tert-butyloxycarbonyl and trifluoromethyl.

In the compounds of the formula II, the radicals R ¹ and R ² and / or R ³ and R ⁴ together with the carbon atoms of the pyrrole ring to which they are bonded preferably represent a condensed ring system with 1, 2 or 3 further rings. If R ¹ and R ² and / or R ³ and R ⁴ stand for a fused-on, ie fused-on ring system, it is preferably benzene or naphthalene rings. Fused benzene rings are preferably unsubstituted and 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 ^a , alkoxycarbonyl, acyl and cyano. Fused naphthalene rings are preferably unsubstituted or have 1, 2 or 3, in particular 1 or 2, of the substituents previously mentioned for the fused benzene rings in the non-fused ring and / or in the fused ring. If R ¹ and R ^{2 are} a fused-on ring system, R ³ and R ^{4 are} preferably hydrogen or R ^{4 is} hydrogen and R ^{3 is} a substituent selected from C ₁ to C ₈ alkyl, preferably C. ₁ - to C ₄ alkyl, especially methyl, ethyl, isopropyl or tert-butyl.

If the use of the compounds of the formula I is intended in an aqueous hydroformylation medium, at least one of the radicals R ¹ , R ² , R ³ and / or R ⁴ preferably represents a polar (hydrophilic) group, in which case, as a rule, during the formation of the complex water-soluble complexes result with a Group VIII metal. The polar groups are preferably selected from COOR ^a , COO ^- M ⁺ , SO ₃ R ^a , SO ₃ ^- M ⁺ , NE ¹ E ² , alkylene-NE ¹ E ² , NE ¹ E ² E ³⁺ X ^- , alkylene- NE ¹ E ² E ³⁺ X ^- , OR ^a , SR ^a , (CHR ^b CH ₂ O) _x R ^a or (CH ₂ CH ₂ N (E ¹ )) _x R ^a , where R ^a , E ¹ , E ² , E ³ , R ^b , M ⁺ , X ^- and x have the meanings given above.

According to a preferred embodiment, B ¹ , B ² , B ³ and B ^{4 are} indolyl radicals. The pyrrole ring in the 3-position may have a substituent other than hydrogen, preferably a C ₁ -C ₄ -alkyl radical.

The bridging heteroaromatic groups B ⁵ and B ⁶ are preferably selected independently of one another from groups of the general formula III


wherein
R ⁵ , R ⁶ , R ⁷ and R ⁸ independently of one another are hydrogen, alkyl, cycloalkyl, heterocycloalkyl, aryl, hetaryl, WCOOR ^a , WCOO ^- M ⁺ , W (SO ₃ ) R ^a , W (SO ₃ ) ^- M ⁺ , WPO ₃ E ¹ E ² , W (PO ₃ ) ^2- (M ⁺ ) ₂ , WNE ¹ E ² , W (NE ¹ E ² E ³ ) ⁺ X ^- , WOR ^a , WSR ^a , (CHR ^b CH ₂ O) _x R ^a , (CH ₂ NE ¹ ) _x R ^a , (CH ₂ CH ₂ NE ¹ ) _x R ^a , halogen, trifluoromethyl, nitro, acyl or cyano,
wherein
W represents a single bond or a divalent bridging group with 1 to 20 bridge atoms,
R ^a , E ¹ , E ² , E ³ each represent the same or different radicals selected from hydrogen, alkyl, cycloalkyl or aryl,
R ^{b represents} hydrogen, methyl or ethyl,
M ^{+ stands} for a cation equivalent,
X ^{- stands} for an anion equivalent and
x represents an integer from 1 to 240,
where two adjacent radicals R ⁵ and R ⁶ and / or R ⁷ and R ⁸ 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, with the proviso that one of the radicals R ⁵ , R ⁶ , R ⁷ or R ^{8 stands} for a chemical bond to a divalent bridging group Y or together with a group Y for a chemical bond which connects the radicals B ⁵ and B ^{6 to} one another.

According to the invention, the compounds of the formula III are bonded to a phosphorus atom of the phosphorus chelate compounds via the pyrrolic nitrogen atom. Furthermore, one of the radicals R ⁵ to R ^{8 stands} for a chemical compound, that is to say the point of attachment of the compound of the formula III to a bridging group Y, or in the case that Y itself is a chemical compound, to a further compound of the formula III , If two compounds of the formula III are directly connected to one another via a chemical bond, they can be identical or different compounds of the formula III, and the compounds of the formula III can be identical or different radicals R ⁵ to R ⁸ (ie identical or different Positions of the pyrrole ring).

In the compounds of the formula III, one of the radicals in the 2-position of the pyrrole ring (ie R ⁵ or R ⁸ ) preferably represents a chemical bond, that is to say the point of attachment to the bridging group Y.

In the compounds of the formula III, one, two or three of the radicals R ⁵ , R ⁶ , R ⁷ and R ⁸ which do not represent a chemical bond are preferably one of the substituents mentioned above other than hydrogen. Preferred compounds of the formula III are those in which the 2-position represents a chemical bond and the 5-position or the 3-, 4-, 5-position represents a substituent other than hydrogen.

The substituents R ⁵ to R ⁸ which are different from hydrogen are preferably selected independently of one another from C ₁ -C ₈ -, preferably C ₁ -C ₄ -alkyl, especially methyl, ethyl, isopropyl and tert-butyl, alkoxycarbonyl, such as methoxycarbonyl, ethoxycarbonyl , Isopropyloxycarbonyl and tert-butyloxycarbonyl and trifluoromethyl.

Furthermore, in the compounds of the formula III, one of the residues in the 2-position of the pyrrole ring (R ⁵ or R ⁸ ) preferably represents a chemical bond and one of the residues in the 5-position together with a residue in the 4-position (R ⁵ and R ⁶ and / or R ⁷ and R ⁸ ) together with the carbon atoms of the pyrrole ring to which they are attached, for a condensed ring system with 1, 2 or 3 further rings. With regard to suitable and preferred condensed ring systems, reference is made to the previous statements regarding corresponding radicals R ¹ and R ² and / or R ³ and R ⁴ in compounds of the formula II. The compound of the formula III then preferably represents an indolyl group.

If the use of the compounds of the formula I is intended in an aqueous hydroformylation medium, then at least one of the radicals R ⁵ , R ⁶ , R ⁷ and / or R ⁸ preferably represents a polar (hydrophilic) group, as previously for the radicals R ¹ to R ⁴ defines what is referred to here.

According to a first preferred embodiment, the bridging group Y stands for a chemical bond, ie in the phosphorus chelate compounds of the general formula I the heteroaromatic groups B ⁵ and B ^{6 are} directly linked to one another.

According to a further preferred embodiment, the bridging group Y is selected from groups of the formulas IV.1 to IV.15




wherein
R ⁹ and R ¹⁰ independently of one another represent hydrogen, alkyl, cycloalkyl, heterocycloalkyl, aryl or hetaryl, where R ⁹ and R ¹⁰ together with the carbon atom to which they are attached also represent a 3- to 8-membered carbo- or Heterocycle, which is optionally additionally fused once, twice or three times with cycloalkyl, heterocycloalkyl, aryl and / or hetaryl,
R ¹¹ , R ¹² , R ¹³ , R ¹⁴ , R ¹⁵ , R ¹⁶ , R ¹⁷ , R ¹⁸ , R ¹¹ ', R ¹² ', R ¹³ 'and R ¹⁴ ' independently of one another for hydrogen, alkyl, cycloalkyl, heterocycloalkyl, Aryl, hetaryl, alkoxy, halogen, SO ₃ H, sulfonate, NE ⁴ E ⁵ , alkylene-NE ⁴ E ⁵ , trifluoromethyl, nitro, alkoxycarbonyl, carboxyl or cyano, where E ⁴ and E ^{5 are} each the same or different radicals mean hydrogen, alkyl, cycloalkyl and aryl,
M stands for a zero-valent transition metal, in particular Fe,
m and n both represent 0 or both represent 1,
Z represents O, S, NR ¹⁹ or SiR ¹⁹ R ²⁰ , where R ¹⁹ and R ²⁰ independently represent hydrogen, alkyl, cycloalkyl, heterocycloalkyl, aryl or hetaryl,
or Z represents a C ₁ to C ₃ 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 ₃ -alkylene bridge which is interrupted by O, S or NR ¹⁹ or SiR ¹⁹ R ²⁰ ,
A ¹ and A ² independently of one another represent O, S, SiR ¹⁹ R ²⁰ , NR ¹⁹ or CR ²¹ R ²² , where
R ²¹ and R ²² independently of one another represent hydrogen, alkyl, cycloalkyl, heterocycloalkyl, aryl or hetaryl or the group R ²¹ together with another group R ²¹ or the group R ²² together with another group R ^{22 form} an intramolecular bridge group D,
D a two-gang bridge group selected from the groups


is where
R ²³ and R ²⁴ 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 ²⁵ , R ²⁶ , R ²⁷ and R ²⁸ independently of one another for hydrogen, alkyl, cycloalkyl, aryl, halogen, trifluoromethyl, COOH, carboxylate, cyano, alkoxy, SO ₃ H, sulfonate, NE ⁴ E ⁵ , alkylene-NE ⁴ E ⁵ E ⁶⁺ X ^- , acyl or nitro, where X ^{- stands} for an anion equivalent, and
c is 0 or 1.

Y is preferably a group of the formula IV.1, where R ⁹ and R ^{10 are} hydrogen and m and n are both 0.

Y is furthermore preferably a group of the formula IV.1, in which R ^{9 is} C ₁ -C ₄ -alkyl, in particular methyl or ethyl, C ₁ -C ₄ -alkoxy, in particular methoxy, or phenyl and in which R ^{10 is} hydrogen stands. In these compounds, m and n are preferably both 0.

Y is furthermore preferably a compound of the formula IV.1, in which R ⁹ and R ^{10 are} both selected independently of one another from C ₁ -C ₄ -alkyl radicals. In particular, R ⁹ and R ¹⁰ are both methyl.

Furthermore, Y preferably represents a group of the formula IV.1, in which R ⁹ and R ¹⁰ together with the carbon atom to which they are attached represent a 3 to 8-membered carbocycle or heterocycle which, if appropriate, additionally , fused two or three times with cycloalkyl, heterocycloalkyl, aryl and / or hetaryl. In these compounds m and n are preferably either both 0 or both 1. Particularly preferably R ⁹ and R ¹⁰ together represent cyclopentyl.

Y is furthermore preferably a group of the formula IV.3, in which R ¹¹ and R ¹² are selected independently of one another from hydrogen and C ₁ -C ₄ -alkyl radicals.

Y is furthermore preferably a group of the formula IV.5, where R ¹¹ and R ^{12 are} hydrogen.

In formulas IV.6 and IV.7, R ¹¹ and R ^{12 are} preferably both hydrogen.

Y is furthermore preferably a group of the formula IV.8, where R ¹¹ , R ¹² , R ¹³ and R ^{14 are} hydrogen.

Y is furthermore preferably a group of the formula IV.9, where M is Fe and R ¹¹ , R ¹² , R ¹³ , R ¹⁴ , R ¹¹ ', R ¹² ', R ¹³ 'and R ¹⁴ ' are hydrogen , The two cyclopentadienyl rings of metallocene IV.9 can exist in an ecliptic and staggered conformation. The levels of the cyclopentadienyl rings can e.g. B. depending on the central metal, parallel or inclined to each other.

Y is furthermore preferably a group of the formula IV.11, where R ¹¹ , R ¹² , R ¹³ and R ^{14 are} hydrogen.

Y is furthermore preferably a group of the formula IV.15.

In the bridging group Y of the formula IV.15, the groups A ¹ and A ^{2 can,} in general, independently of one another represent O, S, SiR ¹⁹ R ²⁰ , NR ¹⁹ or CR ²¹ R ²² , the substituents R ¹⁹ and R ²⁰ in general independently of one another are hydrogen, alkyl, cycloalkyl, heterocycloalkyl, aryl or hetaryl, whereas the groups R ²¹ and R ²² independently of one another represent hydrogen, alkyl, cycloalkyl, heterocycloalkyl, aryl or hetaryl or the group R ²¹ together with another Group R ²¹ or the group R ²² together with another group R ²² can form an intramolecular bridge group D.

D is a double-bonded bridge group that is generally selected from the groups


in which R ²³ and R ²⁴ 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 group and R ²⁵ , R ²⁶ , R ²⁷ and R ²⁶ independently of one another for hydrogen, alkyl, cycloalkyl, aryl, halogen, trifluoromethyl, COOH, carboxylate, cyano, alkoxy, SO ₃ H, sulfonate, NE ⁴ E ⁵ , alkylene-NE ⁴ E ⁵ E ⁶⁺ X ^- , aryl or nitro. The groups R ²³ and R ²⁴ are preferably hydrogen, C ₁ -C ₁₀ alkyl or carboxylate and the groups R ²⁵ , R ²⁶ , R ²⁷ and R ^{28 are} hydrogen, C ₁ -C ₁₀ alkyl, halogen, in particular fluorine , Chlorine or bromine, trifluoromethyl, C ₁ -C ₄ alkoxy, carboxylate, sulfonate or C ₆ -C ₈ aryl. R ²³ , R ²⁴ , R ²⁵ , R ²⁶ , R ²⁷ and R ²⁸ are particularly preferably hydrogen. For use in an aqueous reaction medium, preference is given to compounds in which 1, 2 or 3, preferably 1 or 2, in particular 1 of the groups R ²⁵ , R ²⁶ , R ²⁷ and / or R ²⁸ for a COO ^- M ⁺ , are 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 ²¹ forms an intramolecular bridge group D with a further group R ²¹ or R ²² with a further group R ²² , ie the index c in this case is 1, it is inevitable that both A ¹ and A ^{2 are} CR ²¹ R ²² group and the 1 bridge group Y in this case has a triptycene-like carbon skeleton.

In addition to those with triptycene-like carbon skeletons, preferred bridging groups Y are those in which the index c is 0 and the groups A ¹ and A ^{2 are} selected from the groups O, S and CR ²¹ R ²² , in particular under O, S, the Methylene group (R ²¹ = R ²² = H), the dimethylmethylene group (R ²¹ = R ²² = CH ₃ ), the di-n-propylmethylene group (R ²¹ = R ²² = n-propyl) or the di-n-butylmethylene group (R ²¹ = R ²² = n-butyl). In particular, those bridge groups Y are preferred in which A ¹ is different from A ² , where A ^{1 is} preferably a CR ²¹ R ²² group and A ^{2 is} preferably an O or S group, particularly preferably an oxa group O.

Particularly preferred bridge groups Y of the formula IV.15 are therefore those which are composed of a triptycene-like or xanthene-like (A ¹ : CR ²¹ R ²² , A ² : O) framework.

In formula IV.15, the substituents R ¹¹ , R ¹² , R ¹³ and R ^{14 are} preferably hydrogen, alkyl, cycloalkyl, heterocycloalkyl, aryl and hetaryl. R ¹¹ and R ¹³ are preferably hydrogen and R ¹² and R ^{14 are} C ₁ -C ₄ alkyl, such as. B. methyl, ethyl, n-propyl, n-butyl or tert-butyl.

In formula IV.15, the substituents R ¹¹ , R ¹² , R ¹³ and R ¹⁴ are preferably all hydrogen.

If in formula IV.15 R ¹¹ and / or R ¹³ stand for a fused-on, ie fused, ring system, then it is preferably 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 ^a , 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.

A few are listed below only to illustrate phosphorus chelate compounds according to the invention:

The phosphorus chelate compounds of the general formula I according to the invention can be prepared, for example, according to the following scheme:

In it, B ¹ , B ² , B ⁵ , B ⁶ , R ¹ , R ² , R ³ and R ⁴ independently of one another have the aforementioned meaning.

For example, the production of phosphorus chelate compounds with a bis-indolyl backbone starting from toluidines can be carried out according to the following scheme:

Such syntheses are described, for example, in GB 330,332 and by Madelung in Chem. Ber. 1912, 45, p. 1131 ff. which is fully referred to here.

The preparation of phosphorus-chelate compounds with backbones, in which two indole groups are connected to one another by different bridging groups Y, can be carried out according to the Fischer-indole synthesis starting from phenylhydrazone and the corresponding diketones. This is illustrated using the following scheme as an example:

Such syntheses are described, for example, in Houben-Weyl, Georg Thieme Verlag Stuttgart, 1994, Hetarene I, Part 2b, pp. 716-735; Robinson, Chem. Rev. 1969, 69, pp. 227-250 and Schöpf, Chem. Ber. 1954, 87, pp. 455-463, whereupon in full Reference is made.

The production of phosphorus-chelate compounds with backbones, in which two indole groups are connected by different bridging groups Y, can also be carried out according to the following scheme:

Such syntheses are described, for example, in Babu et al., Synthetic Commun. 30 (9), 1609-1614 (2000); Dittmann, Arch. Pharm. 1985, 318, N4, pp. 340-350 and Brieskorn, Arch. Pharm. 1979, 312 NO 12, Pp. 1046-1051, to which reference is made in full here is taken.

Another object of the invention is a catalyst, comprising at least one complex of a metal of subgroup VIII with at least one compound of the formula I according to the invention, as previously defined.

The catalysts according to the invention and used according to the invention can have one or more of the compounds of the general formula I as ligands. In addition to the ligands of the general formula I described above, you can also at least one further ligand, which is selected from halides, amines, carboxylates, acetylacetonate, aryl or alkyl sulfonates, hydride, CO, olefins, dienes, cycloolefins, nitriles, N-containing Heterocycles, aromatics and heteroaromatics, ethers, PF ₃ , phospholes, phosphabenzenes and monodentate, bidentate and multidentate phosphine, phosphinite, phosphonite, phosphoramidite and phosphite ligands.

The metal of subgroup VIII is preferably Cobalt, ruthenium, rhodium, palladium, platinum, osmium or Iridium and especially cobalt, rhodium, ruthenium and iridium.

In general, under hydroformylation conditions, catalytically active species of the general formula H _x M _y (CO) _z L _{q are} formed from the catalysts or catalyst precursors used in each case, in which M is a metal of subgroup VIII, L is a phosphorus-containing compound of the formula I and q , x, y, z are integers, depending on the valency and type of the metal and the binding nature 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 2 to 5. The complexes can, if desired, additionally have at least one of the other ligands described above.

According to a preferred embodiment, the Hydroformylation catalysts in situ, in which for the Hydroformylation used reactor. If desired, However, the catalysts of the invention can also be used separately are prepared and isolated by conventional methods. To in In situ preparation of the catalysts of the invention can be done, for. B. at least one compound of general formula I, one Compound or a complex of a metal of subgroup VIII, optionally at least one additional ligand and optionally an activating agent in an inert React 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 rhodium complexes, such as rhodium biscarbonylacetylacetonate, Acetylacetonatobisethylene rhodium (I) etc. are preferred Rhodium biscarbonylacetylacetonate or rhodium acetate 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. RuHCl (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, whose amine or hydrate complexes, cobalt carboxylates, such as Cobalt acetate, cobalt ethyl hexanoate, cobalt naphthanoate, and the cobalt Caprolactamate complex. Here too, the carbonyl complexes of Cobalt such as dicobalt octacarbonyl, tetracobalt dodecacarbonyl and Hexacobalthexadecacarbonyl can be used.

The named and other suitable compounds of cobalt, Rhodium, ruthenium and iridium are known in principle and in adequately described in the literature or they can be dated Those skilled in the art are prepared analogously to the compounds already known become.

Suitable activating agents are e.g. B. Brönsted acids, Lewis acids, such as. B. BF ₃ , AlCl ₃ , ZnCl ₂ , and Lewis bases.

The aldehydes are preferably used as solvents, which result from the hydroformylation of the respective olefins, as well as their higher-boiling secondary reaction products, e.g. B. the Products of aldol condensation. Also suitable solvents are aromatics, such as toluene and xylenes, hydrocarbons or Mixtures of hydrocarbons, also for diluting the above mentioned aldehydes and the derivatives of the aldehydes. Further Solvents are esters of aliphatic carboxylic acids with alkanols, for example ethyl acetate or Texanol ™ ether such as tert-butyl methyl ether and tetrahydrofuran. With enough hydrophilized Ligands can also alcohols, such as methanol, ethanol, n-propanol, Isopropanol, n-butanol, isobutanol, ketones such as acetone and Methyl ethyl ketone, etc. can be used. Furthermore, as Solvents also called "ionic liquids" can be used. in this connection it is 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-butylpyridinium salts, Tetraalkylphosphonium salts such as the trishexyl (tetradecyl) phosphonium salts, z. B. the tetrafluoroborates, acetates, tetrachloroaluminates, Hexafluorophosphates, chlorides and tosylates.

Furthermore, it is also possible to implement 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 contain another solvent. For this purpose, ligands of the formula I are used which are modified with polar groups, for example ionic groups such as SO ₃ Me, CO ₂ Me with Me = Na, K or NH ₄ or like N (CH ₃ ) ₃ ⁺ . 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.

The molar ratio of phosphorus ligand to metal VIII. Subgroup is generally in the range of about 1: 1 to 1000: 1.

As substrates for the invention In principle, hydroformylation processes are all compounds which have a or contain several ethylenically unsaturated double bonds. These include e.g. B. olefins, such as α-olefins, internal straight-chain and internal branched olefins. Suitable α-olefins are e.g. B. Ethylene, propene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-non, 1-decene, 1-undecene, 1-dodecene etc.

Suitable branched, internal olefins are preferably C ₄ -C ₂₀ olefins, such as 2-methyl-2-butene, 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 furthermore C ₅ -C ₈ cycloalkenes, such as cyclopentene, cyclohexene, cycloheptene, cyclooctene and their derivatives, such as, for. B. whose C ₁ -C ₂₀ alkyl derivatives with 1 to alkyl substituents. Suitable olefins to be hydroformylated are furthermore 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 acid, maleic acid, fumaric acid, crotonic acid, itaconic acid, methyl 3-pentenoate, methyl 4-pentenoate, methyl oleate, methyl acrylate, methyl methacrylate, unsaturated nitriles such as 3-pentenenitrile, 4-pentenenitrile, acrylonitrile, vinyl ethers such as vinyl methyl ether, vinyl ethyl ether, vinyl propyl, etc., C ₁ -C ₂₀ alkenols, alkene diols and alkadienols, such as 2,7-octadienol-1. Suitable substrates are further 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, vinylcyclohexene, dicyclopentadiene, 1,5,9-cyclooctatriene and butadiene homo- and copolymers.

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 (straight-chain) 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.

• - thermisches Cracken (Steamcracken),
• - katalytisches Dehydrieren und
• - chemisches Dehydrieren durch Chlorieren und Dehydrochlorieren.

Preferably, an industrially accessible olefin mixture is used in the hydroformylation process according to the invention, which contains in particular at least one internal linear olefin. These include e.g. B. the Ziegler olefins obtained by targeted ethene oligomerization in the presence of alkyl aluminum catalysts. These are essentially unbranched olefins with a terminal double bond and an even number of carbon atoms. These also include the olefins obtained by ethene oligomerization in the presence of various catalyst systems, e.g. B. the predominantly linear α-olefins obtained in the presence of alkyl aluminum chloride / titanium tetrachloride catalysts and the α-olefins obtained in the presence of nickel-phosphine complex catalysts according to the Shell Higher Olefin Process (SHOP). Suitable technically accessible olefin mixtures are still used in the paraffin dehydrogenation of corresponding petroleum fractions, e.g. B. the so-called petroleum or diesel oil fractions obtained. Essentially three processes are used to convert paraffins, primarily n-paraffins to olefins:

• - thermal cracking (steam cracking),
• - catalytic dehydration and
• - chemical dehydration by chlorination and dehydrochlorination.

Thermal cracking mainly leads to α-olefins, while the other variants give olefin mixtures which are in the Generally also larger proportions of olefins with internal Have double bond. Suitable olefin mixtures are also those olefins obtained in metathesis or telomerization reactions. These include e.g. B. the olefins from the Phillips triolefin process, a modified SHOP process from ethylene oligomerization, Double bond isomerization and subsequent metathesis (Ethenolysis).

Suitable in the hydroformylation process according to the invention usable technical olefin mixtures are still selected among dibutenes, tributes, tetrabutenes, dipropenes, Tripropenes, tetrapropenes, mixtures of butene isomers, in particular Raffinate II, dihexenes, dimers and oligomers from the Dimersol® IFP process, Hüls Octolprocess®, polygas process etc.

A method is preferred which is characterized in that the hydroformylation catalyst is prepared in situ, wherein one at least one compound of formula I, a compound or a complex of a metal of subgroup VIII and optionally an activating agent in an inert solvent the hydroformylation conditions to react.

The hydroformylation reaction can be carried out continuously, semi-continuously or discontinuously.

Suitable reactors for the continuous reaction are Known in the art and z. B. in Ullmann's encyclopedia of technical chemistry, vol. 1, 3rd ed., 1951, p. 743 ff. described.

Suitable pressure-resistant reactors are also known to the person skilled in the art known and z. B. in Ullmann's Encyclopedia of Technical Chemistry, vol. 1, 3rd edition, 1951, pp. 769 ff. in the In general, an autoclave is used for the method according to the invention used, if desired with a stirrer and can be provided with an inner lining.

The composition of the in the inventive method Synthetic gas used from carbon monoxide and hydrogen can in vary widely. The molar ratio of carbon monoxide and hydrogen is usually about 5:95 to 70:30, preferably about 40:60 to 60:40. A is particularly preferred molar ratio of carbon monoxide and hydrogen in the range of used about 1: 1.

The temperature in the hydroformylation reaction is Generally in a range from about 20 to 180 ° C, preferably about 50 up to 150 ° C. The reaction is usually at the partial pressure of the reaction gas at the selected reaction temperature carried out. Generally, the pressure is in the range of about 1 up to 700 bar, preferably 1 to 600 bar, in particular 1 to 300 bar. The reaction pressure can vary depending on the activity of the used hydroformylation catalyst according to the invention can be varied. In general, those according to the invention allow Catalysts based on phosphorus-containing compounds Implementation in a low pressure area, such as in the area from 1 to 100 bar.

The used according to the invention and those according to the invention Hydroformylation catalysts can be prepared according to the usual Processes known to those skilled in the art of discharging the Separate hydroformylation reaction and can generally be used again for the Hydroformylation can be used.

The catalysts according to the invention described above, the chiral compounds of general formula I include, are suitable for enantioselective hydroformylation.

The catalysts described above can also be used in a more suitable manner Way, e.g. B. by connection via suitable as anchor groups functional groups, adsorption, grafting, etc. on one suitable carrier, e.g. B. made of glass, silica gel, synthetic resins etc., be immobilized. They are also suitable for use as Solid-phase catalysts.

The hydroformylation activity of catalysts based on Surprisingly, ligands of the formula I are generally higher than the isomerization activity with respect to formation central double bonds. The show advantageously catalysts according to the invention and the catalysts used according to the invention high selectivity in the hydroformylation of α-olefins in favor of the α-aldehydes or alcohols. In addition, in Generally also in the hydroformylation of internal linear Olefins (isomerizing hydroformylation) have good yields α-aldehydes or alcohols and in particular also on n-aldehydes or - Get alcohols. Furthermore, these catalysts have Generally high stability among the Hydroformylation conditions so that you usually with longer catalyst service life can be achieved than with the state of the art known catalysts based on conventional chelate ligands. The inventive and Catalysts used according to the invention continue to have high activity, so that usually the corresponding aldehydes or alcohols can be obtained in good yields. In the hydroformylation of Show α-olefins and internal linear olefins also a very low selectivity to the hydrogenation product of olefins used.

• a) Buten oder ein Buten enthaltendes C₄-Kohlenwasserstoffgemisch in Gegenwart eines Katalysators, wie zuvor definiert, mit Kohlenmonoxid und Wasserstoff unter Erhalt eines n-Valeraldehyd enthaltenden Hydroformylierungsprodukts hydroformyliert,
• b) gegebenenfalls das Hydroformylierungsprodukt einer Auftrennung unter Erhalt einer an n-Valeraldehyd angereicherten Fraktion unterzieht,
• c) das in Schritt a) erhaltene Hydroformylierungsprodukt oder die in Schritt b) erhaltene an n-Valeraldehyd angereicherte Fraktion einer Aldolkondensation unterzieht,
• d) die Produkte der Aldolkondensation mit Wasserstoff katalytisch zu Alkoholen hydriert, und
• e) gegebenenfalls die Hydrierprodukte einer Auftrennung unter Erhalt einer an 2-Propylheptanol angereicherten Fraktion unterzieht.

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

• a) butene or a butene-containing C ₄ -hydrocarbon mixture in the presence of a catalyst, as previously defined, hydroformylated with carbon monoxide and hydrogen to give a hydroformylation product containing n-valeraldehyde,
• b) optionally subjecting the hydroformylation product to separation to obtain a fraction enriched in n-valeraldehyde,
• c) subjecting the hydroformylation product obtained in step a) or the fraction enriched in n-valeraldehyde obtained in step b) to an aldol condensation,
• d) the products of the aldol condensation are hydrogenated catalytically to give alcohols, and
• e) optionally subjecting the hydrogenation products to separation to obtain a fraction enriched in 2-propylheptanol.

a) 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. C ₄ cuts, which are available in large quantities from FCC plants and from steam crackers, are preferably suitable. These consist essentially of a mixture of the isomeric butenes and butane.

Suitable feedstock C ₄ hydrocarbon streams include e.g. B. 50 to 99, preferably 60 to 90 mol% of butenes and 1 to 50, preferably 10 to 40 mol% of butanes. The butene fraction preferably comprises 40 to 60 mol% of 1-butene, 20 to 30 mol% of 2-butene and less than 5 mol%, in particular less than 3 mol%, of isobutene (based on the butene fraction). The so-called raffinate II is used as a particularly preferred feedstock, which is an isobutene-depleted C _{4 cut} from an FCC system or a steam cracker.

Hydroformylation catalysts based on the invention have used phosphorus chelate compounds as ligands advantageously high n selectivity, even when using 2-butene and 2-butene-containing hydrocarbon mixtures as Input material. Thus, in the method according to the invention such feedstocks can also be used economically because the desired n-valeraldehyde results in good yields.

b) separation

According to a suitable process variant, the step a) obtained after separation of the catalyst system product-enriched fraction of a further separation to obtain an n- Valeraldehyde-enriched fraction subjected. The separation of the hydroformylation product into an n-valeraldehyde enriched fraction and an n-valeraldehyde-depleted fraction is carried out by customary methods known to the person skilled in the art. Distillation using known ones is preferred Separators, such as distillation columns, e.g. B. Soil columns if desired with bells, sieve plates, sieve plates, valves etc. can be equipped, evaporators, such as thin-film evaporators, Falling film evaporator, wiper blade evaporator etc.

c) aldol condensation

Two molecules of C ₅ aldehyde can be condensed to form α, β-unsaturated C ₁₀ 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 a) or after the separation in step b) has further C ₅ aldehydes, such as 2-methylbutanal and optionally 2,2-dimethylpropanal, these also undergo aldol condensation, the condensation products of all possible then Aldehyde combinations result, for example 2-propyl-4-methyl-2-hexenal. A portion of these condensation products, e.g. B. of up to 30 wt .-%, an advantageous further processing to 2-propylheptanol-containing C ₁₀ alcohol mixtures suitable as plasticizer alcohols does not conflict.

d) hydrogenation

The products of the aldol condensation can be catalytically hydrogenated with hydrogen to C ₁₀ alcohols, such as in particular 2-propylheptanol.

For the hydrogenation of the C ₁₀ aldehydes to the C ₁₀ alcohols, the catalysts of the hydroformylation are in principle also generally suitable at higher temperatures; 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 C ₁₀ aldehydes are hydrogenated as a function of the activity of the catalyst, preferably at elevated temperatures and elevated pressure. The hydrogenation temperature is preferably about 80 to 250 ° C., and the pressure is preferably about 50 to 350 bar.

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

e) separation

If desired, the hydrogenation products can be another Separation to obtain a 2-propylheptanol enriched Fraction and a fraction depleted in 2-propylheptanol be subjected. This separation can be done according to the usual Methods known to those skilled in the art, e.g. B. by distillation, respectively.

Hydroformylation catalysts which have a complex of at least one metal from transition group VIII of the Periodic Table, which has at least one chelate phosphorus compound of the general formula I as ligands, are advantageously suitable for use in a process for the preparation of 2-propylheptanol. The catalysts have a high n-selectivity, so that both when using essentially pure 1-butene and when using 1-butene / 2-butene-containing hydrocarbon mixtures, such as C ₄ cuts, a good yield of n -Valeraldehyde is obtained. Furthermore, the catalysts used according to the invention are also suitable for double bond isomerization from an internal position to a terminal position, so that n-valeraldehyde is obtained in good yields even when using 2-butene and higher concentrations of hydrocarbon mixtures containing 2-butene. Advantageously, the catalysts based on heteroaromatics used according to the invention show essentially no decomposition under the hydroformylation conditions, ie in the presence of aldehydes. Advantageously, substantially no decomposition products are formed even in the presence of atmospheric oxygen and / or light and / or acids and / or at room temperature and elevated temperatures, such as up to about 150 ° C., so that complex measures are taken to stabilize the hydroformylation catalyst used , especially in the processing, can be dispensed with.

Another object of the invention is the use of Catalysts comprising at least one complex of a metal VIII. Subgroup with at least one compound of the general Formula I, as described above, for hydroformylation, Hydrocyanation, carbonylation and hydrogenation.

The hydrocyanation of olefins is another area of application for the catalysts of the invention. Also the Hydrocyanation catalysts according to the invention comprise complexes of a metal VIII. subgroup, in particular cobalt, nickel, ruthenium, Rhodium, palladium, platinum, preferably nickel, palladium and Platinum and most preferably nickel. Usually that is Metal before zero in the metal complex according to the invention. The Production of the metal complexes can, as already for use previously described as hydroformylation catalysts. The same applies to the in situ production of the invention Hydrocyanation.

A suitable one for producing a hydrocyanation catalyst Nickel complex is e.g. B. Bis (1,5-cyclooctadiene) nickel (0).

If appropriate, the hydrocyanation catalysts can be carried out analogously to that described for the hydroformylation catalysts Processes made in situ.

The invention therefore furthermore relates to a process for the preparation of nitriles by catalytic hydrocyanation, in which the hydrocyanation takes place in the presence of at least one of the catalysts according to the invention described above. Suitable olefins for hydrocyanation are generally the olefins previously mentioned as starting materials for hydroformylation. A special embodiment of the process according to the invention relates to the preparation of mixtures of monoolefinic C ₅ mononitriles with non-conjugated C = C and C CN bonds by catalytic hydrocyanation of 1,3-butadiene or 1,3-butadiene-containing hydrocarbon mixtures and the isomerization / Further reaction to saturated C ₆ dinitriles, preferably adiponitrile in the presence of at least one catalyst according to the invention. When using hydrocarbon mixtures for the production of monoolefinic C ₅ -mononitriles by the process according to the invention, a hydrocarbon mixture is preferably used which has a 1,3-butadiene content of at least 10% by volume, preferably at least 25% by volume, in particular at least 40% by volume .-%, having.

Hydrocarbon mixtures containing 1,3-butadiene are available on an industrial scale. So z. B. in the processing of petroleum by steam cracking of naphtha as a C _{4 cut} hydrocarbon mixture with a high total olefin content, with about 40% to 1,3-butadiene and the rest to monoolefins and polyunsaturated hydrocarbons and alkanes. These streams always contain small amounts of generally up to 5% of alkynes, 1,2-dienes and vinyl acetylene.

Pure 1,3-butadiene can e.g. B. by extractive distillation technically available hydrocarbon mixtures isolated become.

The catalysts of the invention can be used advantageously Hydrocyanation of such olefin-containing, in particular Use hydrocarbon mixtures containing 1,3-butadiene, as a rule even without prior purification of the Hydrocarbon mixture. Possibly included, the effectiveness of Catalyst-affecting olefins, such as. B. alkynes or Cumulenes can, if necessary, undergo hydrocyanation selective hydrogenation removed from the hydrocarbon mixture become. Suitable processes for selective hydrogenation are Known specialist.

The hydrocyanation according to the invention can be carried out continuously, semi-continuously or discontinuously. suitable Reactors for the continuous reaction are known to the person skilled in the art and z. B. in Ullmann's Encyclopedia of Chemical Engineering, Volume 1, 3rd edition, 1951, p. 743 ff. Preferably is for the continuous variant of the invention Process used a cascade of stirred tanks or a tubular reactor. Suitable, optionally pressure-resistant reactors for the semi-continuous or continuous execution are the expert known and z. B. in Ullmann's Encyclopedia of Technical Chemistry, Volume 1, 3rd edition, 1951, pp. 769 ff. in the In general, an autoclave is used for the method according to the invention used, if desired with a stirrer and can be provided with an inner lining.

The hydrocyanation catalysts according to the invention can be by conventional methods known to those skilled in the art of discharging the Separate hydrocyanation reaction and can in general be used again for the hydrocyanation.

Another object of the invention is a method for Carbonylation of compounds that are at least one ethylenic contain unsaturated double bond, by reaction with Carbon monoxide and at least one compound with a nucleophile Group in the presence of a carbonylation catalyst in which as a carbonylation catalyst, a catalyst based on a Ligands of the general formula I used.

Also include the carbonylation catalysts of the invention Complexes of a metal of subgroup VIII, preferably nickel, Cobalt, iron, ruthenium, rhodium and palladium, in particular Palladium. The production of the metal complexes can as before previously in the hydroformylation catalysts and Hydrocyanation catalysts described. The same applies to the in In-situ production of the invention Carbonylation.

Suitable olefins for carbonylation are those generally previously as feedstocks for hydroformylation and hydrocyanation called olefins.

The compounds having a nucleophilic group are preferably selected from water, alcohols, thiols, carboxylic acid esters, primary and secondary amines.

A preferred carbonylation reaction is the transfer of Olefins with carbon monoxide and water to carboxylic acids (Hydrocarboxylation). This particularly includes the conversion of ethylene with carbon monoxide and water to propionic acid.

The invention is illustrated by the following, non-limiting examples. Examples Example 1 Synthesis of Ligand I

a) Synthesis of bisindolyl

120 ml of THF were introduced under nitrogen and 37 ml (425 mmol) Oxalyl chloride added dropwise. After cooling to 0 ° C, a Solution of 90 g (840 mmol) o-toluidine and 117 ml (840 mmol) Triethylamine added dropwise in 190 ml THF. It was 2 h at 0 ° C stirred, then allowed to warm to room temperature with stirring. About 600 ml of water, then 900 ml of ethyl acetate were cautious added and heated to 100 ° C. The resulting solid was filtered off and washed with petroleum ether. Yield: 65%.

33.5 g (859 mmol) were added to 600 ml of tert-butanol with stirring Potassium added and stirred at 50 ° C for 4 h until the potassium was complete was implemented. Then 46 g (172 mmol) N, N-bis-o-tolyloxamide added. The mixture was heated in a sand bath at 88 ° C. the tert-butanol distilled off completely. When the solvent removed the temperature rose to 190 ° C and a white voluminous Solid sublimed off. The reaction temperature then rose to 300 ° C and was held for 1 h. Then was on Cooled to room temperature. 300 ml of water became cautious added. The solid was suction filtered and washed with 200 ml of ethanol Reflux heated. The solid was then suctioned off, washed with pentane and dried. Yield: 50%.

b) Synthesis of ligand I.

8.8 g (38 mmol) bisindolyl were placed in 250 ml THF at -78 ° C. Thereafter, 10.4 g (76 mmol) of PCl ₃ and then 16 g (160 mmol) of triethylamine were added. 17.8 g (152 mmol) indole and 16 g (160 mmol) triethylamine were dissolved in 100 ml THF and added at -75 ° C. The reaction mixture was stirred for three days at room temperature. The triethylamine hydrochloride was then filtered off, the THF was removed from the filtrate in vacuo and the residue was stirred with a mixture of hexane / methanol (90:10).

The resulting white solid was filtered off and washed with methanol. Yield: 80%. ( ³¹ P NMR: 57 ppm).

Example 2 Hydroformylation of a butene / butane mixture with Ligand I

5.1 mg Rh (CO) ₂ acac and 150 mg Ligand I (100 ppm Rh, L: M = 10: 1) were weighed in separately, dissolved in 7.5 g THF, mixed and mixed at 100 ° C with 10 bar Synthesis gas (CO: H ₂ = 1: 2) gassed. After 30 min. The pressure was released, then 5.3 g of butene / butane mixture (45% 1-butene, 40% 2-butene, 15% butanes) were pressed in and hydroformylated for 4 h at 120 ° C. and 17 bar (CO: H ₂ = 1: 1). The conversion of butenes was 58%, the aldehyde selectivity 92% and the linearity 70%.

Claims (8)

1. Phosphorus chelate compounds of the general formula I


wherein
B ¹ , B ² , B ³ , B ⁴ , B ⁵ and B ⁶ independently of one another represent a heteroaromatic group which has at least one aromatic ring with a ring nitrogen atom bonded to the phosphorus atom, and
Y represents a chemical bond or a divalent bridging group with 1 to 20 bridge atoms. 2. Compounds according to claim 1, wherein B ¹ , B ² , B ³ and B ^{4 are} independently selected from groups of the general formula II


wherein
R ¹ , R ² , R ³ and R ⁴ independently of one another are hydrogen, alkyl, cycloalkyl, heterocycloalkyl, aryl, hetaryl, WCOOR ^a , WCOO ^- M ⁺ , W (SO ₃ ) R ^a , W (SO ₃ ) ^- M ⁺ , WPO ₃ E ¹ E ² , W (PO ₃ ) ^2- (M ⁺ ) ₂ , WNE ¹ E ² , W (NE ¹ E ² E ³ ) ⁺ X ^- , WOR ^a , WSR ^a , (CHR ^b CH ₂ O) _x R ^a , (CH ₂ NE ¹ ) _x R ^a , (CH ₂ CH ₂ NE ¹ ) _x R ^a , halogen, trifluoromethyl, nitro, acyl or cyano,
wherein
W represents a single bond or a divalent bridging group with 1 to 20 bridge atoms,
R ^a , E ¹ , E ² , E ³ each represent the same or different radicals selected from hydrogen, alkyl, cycloalkyl or aryl,
R ^{b represents} hydrogen, methyl or ethyl,
M ^{+ stands} for a cation equivalent,
X ^{- stands} for an anion equivalent and
x represents an integer from 1 to 240,
where two adjacent radicals R ¹ and R ² and / or R ³ and R ⁴ 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. 3. Compounds according to claim 1, wherein B ⁵ and B ^{6 are} independently selected from groups of the general formula III


wherein
R ⁵ , R ⁶ , R ⁷ and R ⁸ independently of one another are hydrogen, alkyl, cycloalkyl, heterocycloalkyl, aryl, hetaryl, WCOOR ^a , WCOO ^- M ⁺ , W (SO ₃ ) R ^a , W (SO ₃ ) ^- M ⁺ , WPO ₃ E ¹ E ² , W (PO ₃ ) ^2- (M ⁺ ) ₂ , WNE ¹ E ² , W (NE ¹ E ² E ³ ) ⁺ X ^- , WOR ^a , WSR ^a , (CHR ^b CH ₂ O) _x R ^a , (CH ₂ NE ¹ ) _x R ^a , (CH ₂ CH ₂ NE ¹ ) _x R ^a , halogen, trifluoromethyl, nitro, acyl or cyano,
wherein
W represents a single bond or a divalent bridging group with 1 to 20 bridge atoms,
R ^a , E ¹ , E ² , E ³ each represent the same or different radicals selected from hydrogen, alkyl, cycloalkyl or aryl,
R ^{b represents} hydrogen, methyl or ethyl,
M ^{+ stands} for a cation equivalent,
X ^{- stands} for an anion equivalent and
x represents an integer from 1 to 240,
where two adjacent radicals R ⁵ and R ⁶ and / or R ⁷ and R ⁸ together with the carbon atoms of the pyrrole ring to which they are bonded can also represent a condensed ring system with 1, 2 or 3 further rings,
with the proviso that one of the radicals R ⁵ , R ⁶ , R ⁷ or R ^{8 stands} for a chemical bond to a divalent bridging group Y or together with a group Y stands for a chemical bond which bonds the radicals B ⁵ and B ^{6 to} one another combines. 4. Compounds according to any one of the preceding claims, wherein the bridging group Y is selected from groups of formulas IV.1 to IV.15




wherein
R ⁹ and R ¹⁰ independently of one another represent hydrogen, alkyl, cycloalkyl, heterocycloalkyl, aryl or hetaryl, where R ⁹ and R ¹⁰ together with the carbon atom to which they are attached also represent a 3- to 8-membered carbo- or Heterocycle, which is optionally additionally fused once, twice or three times with cycloalkyl, heterocycloalkyl, aryl and / or hetaryl,
R ¹¹ , R ¹² , R ¹³ , R ¹⁴ , R ¹⁵ , R ¹⁶ , R ¹⁷ , R ¹⁸ , R ¹¹ ', R ¹² ', R ¹³ 'and R ¹⁴ ' independently of one another for hydrogen, alkyl, cycloalkyl, heterocycloalkyl, Aryl, hetaryl, alkoxy, halogen, SO ₃ H, sulfonate, NE ⁴ E ⁵ , alkylene-NE ⁴ E ⁵ , trifluoromethyl, nitro, alkoxycarbonyl, carboxyl or cyano, where E ⁴ and E ^{5 are} each the same or different radicals mean hydrogen, alkyl, cycloalkyl and aryl,
M represents a zero-valent transition metal, in particular Fe,
m and n both represent 0 or both represent 1,
Z represents O, S, NR ¹⁹ or SiR ¹⁹ R ²⁰ , where R ¹⁹ and R ²⁰ independently represent hydrogen, alkyl, cycloalkyl, heterocycloalkyl, aryl or hetaryl,
or Z represents a C ₁ to C ₃ 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 ₃ -alkylene bridge which is interrupted by O, S or NR ¹⁹ or SiR ¹⁹ R ²⁰ ,
A ¹ and A ² independently of one another represent O, S, SiR ¹⁹ R ²⁰ , NR ¹⁹ or CR ²¹ R ²² , where
R ²¹ and R ²² independently of one another represent hydrogen, alkyl, cycloalkyl, heterocycloalkyl, aryl or hetaryl or the group R ²¹ together with another group R ²¹ or the group R ²² together with another group R ^{22 form} an intramolecular bridge group D,
D a two-gang bridge group selected from the groups


is where
R ²³ and R ²⁴ 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 ²⁵ , R ²⁶ , R ²⁷ and R ²⁸ independently of one another for hydrogen, alkyl, cycloalkyl, aryl, halogen, trifluoromethyl, COOH, carboxylate, cyano, alkoxy, SO ₃ H, sulfonate, NE ⁴ E ⁵ , alkylene-NE ⁴ E ⁵ E ⁶⁺ X ^- , acyl or nitro, where X ^{- stands} for an anion equivalent, and
c is 0 or 1. 5. A catalyst comprising at least one complex of a metal VIII. Subgroups, the ligands as at least one Compound of general formula I as in one of the claims 1 to 4 defined. 6. Process for hydroformylation of compounds that contain at least one ethylenically unsaturated double bond, by reaction with carbon monoxide and hydrogen in Presence of a catalyst as defined in claim 5. 7. A process for the preparation of 2-propylheptanol, in which a) butene or a butene-containing C ₄ -hydrocarbon mixture in the presence of a catalyst as defined in claim 5, hydroformylated with carbon monoxide and hydrogen to give an hydroformylation product containing n-valeraldehyde, b) optionally subjecting the hydroformylation product to separation to obtain a fraction enriched in n-valeraldehyde, c) subjecting the hydroformylation product obtained in step a) or the fraction enriched in n-valeraldehyde obtained in step b) to an aldol condensation, d) the products of the aldol condensation are hydrogenated catalytically to give alcohols, and e) optionally subjecting the hydrogenation products to separation to obtain a fraction enriched in 2-propylheptanol. 8. Use of a catalyst as defined in claim 5 for hydroformylation, carbonylation, hydrocyanation or for hydrogenation.