WO2001021586A1

WO2001021586A1 - Metallo-organo catalyst for polymerizing unsaturated compounds

Info

Publication number: WO2001021586A1
Application number: PCT/EP2000/009076
Authority: WO
Inventors: Andrei Gonioukh; Marc Oliver Kristen; Wolfgang Micklitz; Benno Bildstein; Christoph Amort
Original assignee: Basf Aktiengesellschaft
Priority date: 1999-09-20
Filing date: 2000-09-15
Publication date: 2001-03-29
Also published as: KR20020059411A; JP2003509490A; DE19944993A1; EP1216229A1

Abstract

The invention relates to 1,2-di-imines with at least one nitrogen-heterocyclic ligand which is bonded to at least one of the two imine nitrogen atoms by a nitrogen atom; and to a method for producing said 1,2-di-imines. The invention also relates to metal complexes of these 1,2-di-imines with transition metals of groups 8, 9 or 10 of the periodic table, to a method for producing the same and to the use of the metal complexes as catalysts in a method for polymerizing unsaturated compounds. Finally, the invention relates to a method for producing polyolefins by polymerizing unsaturated compounds in the presence of an activator and a catalyst in the form of the metal complex.

Description

Organometallic catalysts for the polymerization of unsaturated

links

The invention relates to 1,2-diimine compounds, a process for their preparation, catalysts with 1,2-diimine ligands, processes for their preparation and their use in the polymerization of unsaturated compounds.

There is great interest in developing novel families of unsaturated compound polymerization catalysts to gain better control over the properties of polyolefins or other novel products.

In particular, the use of transition metal catalysts with late transition metals (in particular transition metals of groups 7, 8, 9 and 10 of the periodic table of the elements) is interesting because of their property to tolerate heteroatom functionalities. It is disadvantageous, however, that the transition metal catalysts with late transition metals, in contrast to the transition metal catalysts with early transition metals (in particular transition metals of subgroups III to V of the Periodic Table of the Elements), frequently cause dimerization or oligomerization of owing to competing β-hydride elimination unsaturated compounds tend.

Transition metal catalysts, which are suitable for the polymerization of unsaturated compounds, are known later from the prior art. VC Gibson et al., Chem. Commun. 1998, 849-850 and M. Brookhart et al., J. Am. Chem. Soc. 1998, 120, 4049-4050, new olefin polymerization catalysts based on Fe (II) and Co (II) are disclosed. These catalysts carry 2,6-bis (imino) pyridyl ligands which are aryl-substituted on the imino nitrogen atoms and show high activities in the polymerization of ethylene. The polyethylene obtained is essentially linear and the molecular weight is strongly dependent on the substituents on the aryl radical. H. tom Dieck, Z. Naturforsch. 1981, 36b, 823-832, describes bis (diazadiene) nickel (O) complexes with aromatic substituents on the nitrogen atom, and their conformations as a function of the substituents on the aromatic radical. In M. Brookhart et al., J. Am. Chem. Soc. 1995, 117, 6415-6415, catalysts based on Pd (II) and Ni (II) are described for the polymerization of ethylene and α-olefins. These catalysts carry 1,2-diimine ligands. In the polymerization of ethylene and α-olefins, polymers with a high molecular weight are obtained. Depending on the ligand system, metal, the temperature and the pressure, the branching of polyethylene produced with these catalysts can be set from strongly to slightly branched. According to M. Brookhart et al., J. Am. Chem. Soc. 1996, 118, 267-268, these catalysts with Pd (II) as the metal also enable the copolymerization of ethylene and propylene with functionalized vinyl monomers. WO 96/23010 relates to processes for the polymerization and copolymerization of olefins such as ethylene, acrylic olefms and others. Transition metal compounds with metals from the group Ti, Zr, Sc, V, Cr, rare earth metals, Se, Co, Ni and Pd are used as catalysts. Diimine ligand systems, in particular 1,2-diimine ligand systems, are disclosed as ligand systems. The object of the present invention is to provide a new catalyst with a transition metal from group 8, 9 or 10 of the Periodic Table of the Elements (late transition metal) as the central metal for the polymerization of unsaturated compounds. This task is divided into the provision of a ligand system for this catalyst, as well as a method for producing this ligand system and the provision of a method for producing the corresponding catalyst.

This object is achieved by 1,2-diimines of the general formula (I)

in which the symbols have the following meaning:

R ¹ radicals of the general formula NR ⁵ R ⁶ , R ² radicals of the general formula NR ⁵ R ⁶ or alkyl, aryl or

cycloalkyl,

R ⁵ and R ⁶ together with the N atom form a 5-, 6- or 7-membered ring in which one or more of the -CH or -CH ₂ groups can be replaced by suitable heteroatom groups, which is saturated, unsaturated and unsubstituted, substituted or fused with further carbacyclic or heterocarbacyclic 5- or 6-membered rings, which in turn can be saturated or unsaturated and substituted or unsubstituted, and

R ³ , R ⁴ independently of one another are H, alkyl, aryl or cycloalkyl radicals or

R ³ and R ⁴ together form a cyclic radical, so that, including the two imine carbon atoms, a carbacyclic or heterocarbacyclic 5- to 8-membered ring is formed which is saturated or unsaturated and unsubstituted, substituted or with other carbacyclic or heterocarbacyclic 5 - or 6-membered rings, which in turn can be saturated or unsaturated and substituted or unsubstituted, can be fused. The 1,2-diimines according to the invention are distinguished in that they have at least one nitrogen-nitrogen bond between at least one of the two imine nitrogen atoms and at least the radical R ¹ .

These compounds are particularly suitable as ligand systems for the production of novel, efficient catalyst systems for the polymerization or copolymerization of unsaturated compounds. These new ligands are easy to prepare and allow a wide range of residues to be varied. This makes this system very variable and allows the customization of ligand and complex systems for various purposes.

Above and below, alkyl radicals are generally understood to mean linear or branched Cp to C o-alkyl radicals, preferably C to Cio-alkyl radicals, particularly preferably C 1 to C ₈ -alkyl radicals. These alkyl residues can be heteroatom-substituted. Suitable alkyl radicals are, for example, methyl, i-propyl, t-butyl, trifluoromethyl and trimethylsilyl radicals.

Aryl radicals are generally understood to mean unsubstituted and substituted C ₆ to C ₂₀ aryl radicals, preferably C ₆ to C ₁₄ aryl radicals which can be mono- or polysubstituted, and very particularly preferred are C to C ₆ to C ₆ alkyl radicals ₆ - to Cio-aryl residues such as 4-methylphenyl, 2,6-dimethylphenyl, 2,6-diethylphenyl, 2,6-diisopropylphenyl, 2-tert-butylphenyl, 2,6-di (tert-butyl) phenyl or 2 -i-propyl-6-methylphenyl. The aryl radicals can also be substituted with hetero atoms, for example with F. Cycloalkyl radicals are generally understood to mean C to C ₈ cycloalkyl radicals (the number of carbon atoms relates to the carbon atoms in the cycloalkyl ring), which can be unsubstituted or substituted one or more times by alkyl or aryl radicals. C ₅ to C ₆ cycloalkyl radicals are preferred. According to the present invention, R ⁵ and R together with the N atom can form a 5- or 6-membered ring in which one or more of the —CH or —CH groups can be replaced by suitable heteroatom groups. Suitable hetero atom groups are preferably -N or -NH groups. Particularly preferably, no to 3 -CH or -CH ₂ groups are replaced by -N- or - NH groups.

The 5-, 6- or 7-membered ring can be saturated or unsaturated. The ring can be unsaturated one or more times. Unsaturated 5-membered rings are preferred. Unsaturated rings should also be understood to mean, in the case of the 5-membered rings, aromatic rings such as unsubstituted or substituted pyrrole radicals, which are particularly preferred.

The 5-, 6- or 7-membered ring can be unsubstituted, substituted or fused with other carbacyclic or heterocarbacyclic 5- or 6-membered rings, which in turn can be saturated or unsaturated and substituted or unsubstituted. Carbacyclic rings are understood to mean those rings which have a pure carbon skeleton. In the heterocarbacyclic rings, one or more -CH - or -CH- groups are formed by heteroatoms, preferably -NH- or -N- Groups, replaced. Heterocarbacyclic rings with a nitrogen atom in the ring system are particularly preferred.

The above-mentioned alkyl, aryl or cycloalkyl radicals are suitable as substituents in these carbacyclic and heterocarbacyclic 5- or 6-membered rings. The rings can be substituted one or more times. A 1 to 3-fold substitution is preferred. The ring system can furthermore be ortho- or ortho- and peri-fused. The system is preferably ortho-fused, with particularly preferably 1 to 2 phenyl radicals fused to the central 5- or 6-ring, such as indole, carbazole or derivatives thereof. In a particularly preferred embodiment, the ring is 5-membered. A non-fused 5-ring, in particular a pyrrole radical or a radical derived from pyrrole, in which none, one or more, preferably 0 to 3, particularly preferably 0 or 2, -CH groups in the pyrrole ring can be replaced by nitrogen, is very particularly preferred , Examples of this are the pyrrole and triazole systems. Especially preferred are pyrrole radicals or radicals derived from pyrrole which in the 2- and 5-position with CJ to C ₆ alkyl groups, linear, branched and can be substituted with heteroatoms and / or aryl groups which are unsubstituted or in turn with Cj - To C ₆ alkyl groups, which can be substituted heteroatom, are substituted. Preferred substituents in the 2- and 5-position of the pyrrole ring are methyl, i-propyl, t-butyl, phenyl, substituted aryl radicals, as defined above.

According to the present invention, R ³ and R ⁴ in the general formula (I) can independently be H, alkyl, aryl or cycloalkyl radicals, preferred radicals being defined above, or together forming a cyclic radical so that, including the two Imine carbon atoms, a carbacyclic or heterocarbacyclic 5- to 8-membered ring, preferably a 5- to 6-membered ring, is formed which is saturated or unsaturated and unsubstituted, substituted or with further carbacyclic or heterocarbacyclic 5- or 6-membered rings which in turn can be saturated or unsaturated and substituted or unsubstituted, fused. R ³ and R ⁴ are preferably H (la), methyl (Ib), or together with the imine carbon atoms form a ring, so that structures of the formulas (Ic) to (Ig) are formed:

in which R ', R ", R'", R '"\ R'" ", R" "" = H, alkyl, cycloalkyl or aryl as defined above, or are trifluoromethyl (Ih), phenyl (Ii ) or furfuryl (Ij).

Compounds of the general formula (I) in which R ¹ , R ² , R ³ and R ^{4 have} the meanings given in the formulas (lai), (Ibj), (Icj) and (Idi) are particularly preferred;

wherein R ⁹ , R ¹⁰ , R ¹¹ and R ¹² independently of one another are C to C ₂₀ alkyl radicals, which can be linear or branched, preferably Ci to C ₁₀ alkyl radicals, particularly preferably Ci to C ₈ alkyl radicals. These alkyl radicals can be heteroatom-substituted. Suitable alkyl radicals are, for example, methyl, i-propyl, t-butyl, trifluoromethyl and trimethylsilyl radicals.

The R \ R '"", R "" "radicals are H, alkyl, aryl or cycloalkyl radicals, as already defined above.

The 1,2-diimines of the general formula (I) according to the invention

embedded image in which

R ¹ radicals of the general formula NR ⁵ R ⁶ ,

R ² radicals of the general formula NR ⁵ R ⁶ or alkyl, aryl or cycloalkyl radicals, and in which the other symbols have the above meanings, are generally prepared by condensation of the corresponding amino compounds with 1,2-diketo compounds. They are very accessible synthetically and it is possible to synthesize a large number of different compounds of the general formula (I) in good yields.

The preferred production process depends on the desired 1,2-diimine. The following are preferred embodiments for the preparation of symmetrical 1, 2-diimines, in which R ¹ = R ² = NR ⁵ R ⁶ , and unsymmetrical diimines, in which R ¹ ≠ R ² and R ^{2 is} a radical of the general formula NR ⁵ R ⁶ , which differs from that in R ¹ , or is an alkyl, aryl or cycloalkyl radical.

In a preferred embodiment, symmetrical 1,2-diimines of the general formula (I), wherein R = R, by reacting compounds of the general formula (II) H ₂ N-NR5R6 (II) in which R ⁵ and R ^{6 have} the meanings given above, prepared with 1,2-diketo compounds of the general formula (III),

wherein

R ³ , R ^{4 have} the meanings given above.

The process has one stage and is carried out under acidic reaction conditions, preferably with the addition of an acid, particularly preferably formic acid, in an alcoholic solution, preferably in methanol. Alternatively, the process can be carried out with aluminum trialkyl catalysis, preferably using trimethylaluminum, in an aprotic solvent, preferably in toluene. The ratio of the compound of the general formula (II) to the compound of the general formula (III) is 2: 0.7 to 1.3, preferably 2: 0.9 to 1.1, particularly preferably 2: 1 Reaction under acidic conditions in methanol / formic acid is generally preferred. The ratio of methanol to formic acid is generally 1: 1 to 1: 5, preferably 1: 1 to 1: 3.

In general, the condensation is carried out at from 0 to 100.degree. C., preferably from 15 to 80.degree. C., particularly preferably from 20 to 40.degree. The reaction time is generally 20 minutes to 48 hours, preferably 1 hour to 16 hours, particularly preferably 2 hours to 14 hours. The exact reaction conditions depend on the compounds used in each case. In the case of particularly voluminous residues in the compounds of the general formulas (II) and (III) which only condense slowly to the desired 1,2-diimines, a reaction with aluminum trialkyl catalysis in aprotic solvents is optionally preferred.

In a further preferred embodiment, the asymmetrical 1,2-diimines of the general formula (I), in which R ¹ ≠ R ² , are prepared in a two-stage process in which:

a) in a first stage compounds of the general formula (II)

H ₂ N-NR5R6 (ii) embedded image in which

R ⁵ and R ^{6 have} the meanings given above, with 1,2-diketo compounds of the general formula (III)

R ³ , R ^{4 have} the above meanings, in a ratio of the compounds of the general formula (II) to the compounds of the general formula (III) from 1: 0.8 to 1.2, preferably from 1: 0.9: 1 , 1, particularly preferably 1: 1, under acidic conditions, preferably with the addition of acids, particularly preferably formic acid, in alcoholic solution, preferably in methanol, to give the corresponding monoimine, the solvent is then removed in vacuo, and b) the monoimine in a second stage with compounds of the general formula (II) which differ from the compounds of the general formula (II) used in stage a), or with compounds of the general formula (IV)

H ₂ N-NR7R8 (TV)

7 R wherein R and R independently of one another are alkyl, aryl or cycloalkyl radicals, or with amines of the general formula (V) R13-H ₂ (V) wherein

R ^{13 is} an alkyl, an aryl or a cycloalkyl radical, as defined above, in aprotic solution, preferably in toluene, with aluminum trialkyl catalysis, preferably with aluminum trimethyl as catalyst, in one Ratio of the monoimine to a compound of the general formula (II) or of the general formula (IV) or (V) from 1: 0.8 to 1.2, preferably from 1: 0.9 to 1.1, particularly preferably from 1 : 1 is implemented.

In general, the condensation in stage a) is carried out at temperatures from 0 to 100 ° C., preferably from 15 to 80 ° C., particularly preferably from 20 to 40 ° C. The reaction time is generally 20 minutes to 48 hours, preferably 1 hour to 16 hours, particularly preferably 2 hours to 14 hours. The exact reaction conditions depend on the compounds used in each case. Step b) is generally carried out at temperatures from 0 to 100 ° C., preferably from 20 to 80 ° C., particularly preferably from 30 to 60 ° C. The reaction time is generally 20 minutes to 48 hours, preferably 1 hour to 16 hours, particularly preferably 2 hours to 7 hours. The exact reaction conditions depend on the compounds used.

Particular preference is given to compounds of the general formula (II)

H ₂ N - NR5R6 (II) woπn

R ⁵ and R ^{6 have} the meanings given above, use compounds in which the group NR ⁵ R ^{6 is} a pyrrole radical or a radical derived from pyrrole, which is very particularly preferably in the 2- and 5-position with d to C ₆ - Alkyl groups which can be linear, branched and substituted with heteroatoms and / or aryl groups which are unsubstituted or in turn substituted with C ₁ -C ₆ -alkyl groups which can be substituted by heteroatoms. Preferred substituents in the 2- and 5-position of the pyrrole ring are methyl, i-propyl, t-butyl, phenyl, substituted aryl radicals, as defined above.

Such N-amino-pyrroles can be obtained, for example, by the following two-stage process: i) reaction of a suitable 1,2-diketone with an equivalent amount

Acetylhydrazine or benzoyloxycarbonylhydrazine in the presence of a catalytic amount of acid, preferably p-toluenesulfonic acid, in an inert organic solvent, preferably toluene, to which corresponding acetyl- or benzoyloxycarbonyl-protected N-amino-pyrrole; ii) hydrolysis of the protected N-amino-pyrrole with an excess base, preferably with potassium hydroxide, in a high-boiling inert organic solvent, preferably in ethylene glycol, to the corresponding free N-amino-pyrrole.

The subsequent workup is carried out in the usual way.

Figure 1 shows an example of the synthesis of 2,5-disubstituted N-aminopyrroles.

Compounds of the general formula (III) are used as 1,2 diketo compounds in the process according to the invention:

in which R ³ and R ^{4 have} the above meaning. Preferred 1,2-diketo compounds are glyoxal (purple), butane-2,3-dione (Illb), generally aromatic ortho-quinones (IIIc), acenaphthenquinone and derivatives thereof (III d), phenanthrenequinone and derivatives thereof (Ille), 1, 2 (ß) -naphthoquinone and derivatives thereof (Ulf), camphorquinone (+/-, 1R, IS) (Illg) and 1,1,1,4,4,4-hexafluoro-2,3-butanedione (Illh ), Benzil (Uli) and Furil (IIIj). Carbonyl compounds of the general formulas (purple), (Illb), (IIIc) or (Illd) are particularly preferably used,

(ffla) (rπb)

in which R ', R "", R'"" = H, alkyl or aryl as defined above. The compounds according to the invention are suitable as ligands for catalysts which can be used for the polymerization of unsaturated compounds. In particular, the compounds according to the invention are ligands for catalysts with a metal of the late transition metals, ie with a

Group 8, 9 or 10 metal of the Periodic Table of the Elements. The present invention therefore furthermore relates to compounds of the general formula (VI) in which the symbols have the following meaning

R ¹ radicals of the general formula NR ⁵ R ⁶ , R ² radicals of the general formula NR ⁵ R ⁶ or alkyl, aryl or cycloalkyl radicals,

R ⁵ and R ⁶ together with the N atom form a 5-, 6- or 7-membered ring in which one or more of the -CH or -CH ₂ groups can be replaced by suitable heteroatom groups, which is saturated, unsaturated and unsubstituted, substituted or fused with further carbacyclic or heterocarbacyclic 5- or 6-membered rings, which in turn can be saturated or unsaturated and substituted or unsubstituted, and R ³ , R ^{4 can} independently be H, alkyl, cycloalkyl or Aryl residues, or

R ³ and R ⁴ together form a cyclic radical so that, including the two imine carbon atoms, a carbacyclic or heterocarbacyclic 5- to 8-membered ring is formed which is saturated or unsaturated and unsubstituted, substituted or with further carbacyclic or heterocarbacyclic 5- or 6-membered rings, which in turn can be saturated or unsaturated and substituted or unsubstituted, fused;

M transition metal of group 8, 9 or 10 of the periodic table of the elements, and

X is a halide or a Cj to C ₆ alkyl radical; n valency of the metal M, preferably 2 or 3.

The transition metal M of group 8, 9 or 10 of the periodic table of the elements is preferably Pd, Co, Ni or Fe. Pd and Ni are particularly preferred. The ligands X can independently of one another be halide or alkyl radicals. It is preferably chloride, bromide or methyl radicals. Particularly preferred as group MX ₂ : PdCl ₂ , Pd (Cl) CH ₃ , NiCl ₂ or NiBr ₂ .

Preferred radicals R ¹ , R ² , R ³ and R ⁴ have the meanings given above.

Compounds of the general formulas (Via) and (VIb) are very particularly preferred:

(Vlai) (VIbi)

(VIc i) (VId i) in which R ', R "", R'"" = H, alkyl, cycloalkyl or aryl as defined above, and wherein

R ⁹ , R ¹⁰ , R ^u and R ¹² independently of one another are C 1 -C ₂₀ -alkyl radicals, which may be linear or branched, preferably C ₁ -C 10 -C]

Alkyl radicals, particularly preferably C 1 to C ₈ alkyl radicals. This

Alkyl radicals can be heteroatom-substituted. Suitable alkyl radicals are, for example, methyl, i-propyl, t-butyl,

Trifluoromethyl and trimethylsilyl residues, and

MX _{2 is} PdCl ₂ , Pd (Cl) CH ₃ , NiCl ₂ , CoCl ₂ , NiBr ₂ or FeCl ₂ , particularly preferably NiBr and PdCl. After activation with an activator (cocatalyst), these complexes are very active in the polymerization of unsaturated compounds. They are easily accessible and can be manufactured in a wide range of variations. This provides a very variable system that allows tailoring of complex systems for the desired application. The compounds of the general formula (V) according to the invention are usually prepared by reacting the corresponding compounds of the general formula (I) with transition metal salts of metals from groups 8, 9 or 10 of the Periodic Table of the Elements.

In a preferred embodiment, a compound of the general formula (I) suitable as a ligand is dissolved in an organic solvent, for example tetrahydrofuran (THF) or methylene chloride, with a corresponding metal salt, for example NiCl ₂ (DME) (DME = 1,2-dimethoxyethane), NiBr ₂ (DME) ₂ , CoCl ₂ , PdCl ₂ (benzonitrile) ₂ , PdClMe (COD) (COD - 1,5-cyclooctadiene) combined. The molar ratio of ligand to metal salt is generally 1.5: 1 to 1: 1.5, preferably 1.2: 1 to 1: 1.2, particularly preferably approximately 1: 1. The reaction mixture is generally at temperatures from room temperature to 50 ° C, preferably from room temperature to 40 ° C, particularly preferably stirred at room temperature for generally 0.5 hours to 16 hours, preferably 1 to 6 hours, particularly preferably 1 to 3 hours. Working up is carried out in a conventional manner, for example by removing the solvent in vacuo, washing the residue with a solvent in which the residue (product) is largely insoluble, for example with diethyl ether, optionally digesting in a non-polar solvent, for example hexane, filtering off, washing and drying.

FIG. 2 and FIG. 3 show examples of the synthesis of selected ligands of the general formula (I) according to the invention and the synthesis of selected metal complexes produced therefrom.

The metal complexes of the general formula (V) according to the invention are easily accessible and are suitable as catalysts for the polymerization of unsaturated compounds. They are characterized by a surprisingly high productivity in the polymerization or copolymerization of unsaturated compounds.

Another object of the present invention is therefore the use of compounds of general formula (VI) as catalysts in a process for the polymerization of unsaturated compounds, and a process for the preparation of polyolefins by polymerization of unsaturated compounds in the presence of the catalyst according to the invention and an activator.

It is known that the structures of polymers and thus also their properties and intended use depend on the catalyst used in the polymerization and the reaction conditions during the polymerization. The catalysts according to the invention thus represent a possibility of providing novel polymers with specific property profiles.

Strong, neutral Lewis acids, ionic compounds with Lewis acid cations and ionic compounds with Bronsted acids are particularly suitable as cations as activators (cocatalysts). Compounds of the general formula (VII) are preferred as strong, neutral Lewis acids,

MX1X2X3 (VII) in which the symbols have the following meaning

M 'an element of III. Main group of the periodic table of the

Elements, preferably B, Al or Ga, particularly preferably B,

X ', X ² , X ³ independently of one another hydrogen, d- to C ₁₀ alkyl, C ₆ - to Ci5-aryl, alkylaryl, arylalkyl, haloalkyl or haloaryl, each having 1 to 10 carbon atoms in the alkyl radical and 6 to 20 carbon atoms in the aryl radical or fluoride, chloride, bromide or iodide, preferably for haloaryls, particularly preferably for pentafluorophenyl. Compounds of the general formula (VII) in which X, X, X are identical are particularly preferred, preferably tris (pentafluorophenyl) borane.

Another preferred neutral Lewis acid used as an activator (cocatalyst) is "R ¹⁴ AlO" (alkylaluminoxane), wherein R ¹⁴ is a CJ to C ₂₅ alkyl, preferably a Ci to C - alkyl group, particularly preferably a methyl radical (methylaluminoxane) is.

Suitable ionic compounds with Lewis acid cations are compounds of the general formula (VIII),

[(Ya ⁺ ) QQ ₂ ... Qz] ^{d +} (VE!) In which the symbols have the following meanings Y is an element of I. to VI. Main group or I. to VIII.

Subgroup of the periodic table of the elements,

Qi to Q _z single negatively charged radicals such as Cj to C ₂₈ alkyl, C ₆ to C ₁₅ aryl, alkylaryl, arylalkyl, haloalkyl, haloaryl each having 6 to 20 carbon atoms in the aryl and 1 to 28 carbon atoms in the alkyl radical, C _\ - to Cι ₀ cycloalkyl, which may optionally be substituted with Ci- to C] ₀ - alkyl groups, halide, C to C ₂₈ alkoxy, C ₆ - to Ci ₅ aryloxy. Silyl or mercaptyl groups, a integers from 1 to 6, z integers from 0 to 5, d difference from az, where d is greater than or equal to 1. Carbonium cations, oxonium cations and sulfonium cations as well as cationic transition metal complexes are particularly suitable. The triphenylmethyl cation, the silver cation and the l, l'-dimethylferrocenyl cation should be mentioned in particular. They preferably have non-coordinating counterions, in particular boron compounds, as they are also mentioned in WO 91/09882, preferably tetrakis (pentafluorophenyl) borate.

Ionic compounds with Bronsted acids as the cation and preferably also non-coordinating counterions are also mentioned in WO 91/09882, the preferred cation is N, N-dimethylanilinium. The amount of activator is preferably 0.1 to 10 equivalents, based on the catalyst (VI). For alkylaluminoxanes, in particular methylaluminoxane, the amount of activator is generally 50 to 1000 equivalents, preferably 100 to 500 equivalents, particularly preferably 100 to 300 equivalents, based on the catalyst (VI). The polymerization process according to the invention is suitable for the production of homopolymers or copolymers. Unsaturated compounds or combinations of unsaturated compounds used with preference are unsaturated compounds selected from ethylene, C ₃ - to C o -monoolefins, ethylene and C ₃ - to C ₂ -monoolefins, cycloolefins, cycloolefins and ethylene and cyclo-olefins and propylene. Preferred cycloolefins are norbornene, norbonadiene and cyclopentene.

The above monomers can be copolymerized with monomers having a carbonyl group such as esters, carboxylic acids, carbon monoxide and vinyl ketones. The following combinations of unsaturated compounds are preferred: ethylene and C ₃ - to C ₂ o -monoolefins, ethylene and an alkyl acrylate, in particular methyl acrylate, ethylene and an acrylic acid, ethylene and carbon monoxide, ethylene, carbon monoxide and an acrylate ester or an acrylic acid. especially methyl acrylate as well as propylene and alkyl acrylate, especially methyl acrylate.

Depending on the reaction conditions and the monomers used, it is possible to obtain homopolymers, statistical copolymers or block copolymers with the process according to the invention. The polymerization is carried out under generally customary conditions in solution, for example as high-pressure polymerization in a high-pressure reactor or high-pressure autoclave, in suspension or in the gas phase (for example GP WS polymerization process). Polymerization in solution is preferred. The corresponding polymerization processes can be carried out as a batch process, semi-continuously or continuously, the procedures being known from the prior art.

The catalyst systems according to the invention can be used in the form of unsupported catalysts or supported catalysts, depending on the polymerization conditions.

When the catalyst systems according to the invention are used, they are homogeneously dissolved in the solution during solution polymerization. The catalysts of the general formula (VI) can be prepared “in situ” and used directly, without prior isolation, in the polymerization. The support materials used are preferably finely divided solids whose particle diameters are generally in the range from 1 to 200 μm, preferably from 30 to 70 μm.

Suitable carrier materials are, for example, silica gels, preferably those of the formula SiO ₂ ^• a Al ₂ O ₃ , in which a stands for a number in the range from 0 to 2, preferably from 0 to 0.5; it is therefore alumosilicates or silicon dioxide. Such products are commercially available, for example Silica Gel 332 from Grace or ES 70x from Crosfield.

These carrier materials can be subjected to a thermal or chemical treatment or calcined to remove adsorbed water, a treatment preferably being carried out at 80 to 200 ° C., particularly preferably at 100 to 150 ° C.

Other inorganic compounds such as Al ₂ O ₃ or MgCl ₂ or mixtures containing these compounds can also be used as carrier materials. The catalysts can also be prepared “in situ” in the presence of support material. Aprotic organic solvents are particularly suitable as solvents. The catalyst system, the monomer (s) and the polymer can be soluble or insoluble in these solvents, but the solvents should not participate in the polymerization. Suitable solvents are alkanes, cycloalkanes, selected halogenated hydrocarbons and aromatic hydrocarbons. Preferred solvents are hexane, toluene and benzene, toluene is particularly preferred.

The polymerization temperatures in solution polymerization are generally in the range from -20 to 350 ° C., preferably from 0 to 350 ° C., particularly preferably from +20 to 100 ° C., very particularly preferably from room temperature to 80 ° C. The reaction pressure is generally 0.1 to 3000 bar, preferably 0.1 to 2000 bar, particularly preferably 1 to 200 bar, very particularly preferably 5 to 40 bar. The polymerization can be carried out in any apparatus suitable for the polymerization of unsaturated compounds.

To control the molecular weight of the polymers, the polymerization can be carried out in the presence of hydrogen gas, which acts as a chain transfer reagent. Usually, the higher the hydrogen concentration, the lower the average molecular weight. Furthermore, other auxiliaries customary in the corresponding polymerization process can be used.

The polymerization process according to the invention opens up access to polyolefins with novel structures and properties. The present invention therefore furthermore relates to polymers which can be prepared by the process according to the invention.

The following examples further illustrate the invention.

Examples

(The numbering of the example compounds is independent of the numbering of the compounds in the description.) The ligand and complex syntheses were carried out with the exclusion of air and moisture. The equipment and reagents used were prepared accordingly. A Synthesis of 2,5-disubstituted N-aminopyrroles

Example 1:

General procedure for the synthesis of the benzoyloxycarbonyl-protected 2,5-disubstituted N-aminopyrroles 2a-d (FIG. 1) 4-8 g of the 1,4-diketones la-d were added together with an equivalent of benzoyloxycarbonylhydrazine and a catalytic amount of p-toluenesulfonic acid 80 ml of toluene heated under reflux. After 18 hours the solution was cooled and the solvent removed under reduced pressure. The white crystalline residues were powdered and refluxed in a suitable solvent mixture (THF / hexane 1: 4 or CHC1 ₃ / hexane 1: 5), so that a saturated solution was formed, from which the compounds 2a-d then crystallized out on cooling. These were filtered and dried in a high vacuum.

Preparative and analytical data of the benzoyloxycarbonyl-protected 2,5-disubstituted N-aminopyrroles: Compound 2a:

Yield 85%, Cι ₄ Hι ₆ N ₂ O ₂ , mp: 104-108 ° C, Η NMR (CDC1 ₃ ): δ 1.97 (s 6H methyl), 5.1 1 (s 2H CT C _Ö H « ;), 5.67 (s 2H pyrrole), 7.26 (s 5H phenyl); MS: M ⁺ = 224.5 m / z.

Compound 2b: yield 88.6%, C ₁₈ H ₂₄ N ₂ O ₂ , m.p .: 118-121 ° C, (NMR (CDC1 ₃ ): δ 1.18 (d 12H methyl), 2.75 (m 2H CH (CH ₃ ) ₂ ), 5.20 (pd 2H CH ^ H *,), 5.84 (2H pyrrole), 7.3 (m 5H phenyl); MS: M ⁺ = 166.5 m / z.

Connection 2c:

Yield 78.1% C2oH ₂₈ N ₂ θ2, mp: 155-158 ° C, Η NMR (CDC1 ₃ ): δ 1.25 / 1.33 (18H t-butyl), 5.24 / 5.15 (pd 2H

5.82 / 5.79 (pd 2H pyrrole), 7.28 (s 1H NH), 7.4 (m 5H phenyl); MS: M ⁺ = 328 m / z.

Connection 2d:

Yield 84.2%, C2Ä0N2O2, m.p .: 194-197 ° C, 1H NMR (CDCI ₃ ): δ 5.04 / 5.1 (pseudo d 2H CT CeH _ό ), 6.46 (s 2H pyrrole), 7.01 (s 1 H NH), 7.1-7.5 (m 15 H phenyl); MS: M ⁺ = 368.5 m / z. Example 2:

General procedure for the selective removal of the benzoyloxycarbonyl protective group, synthesis of the aminopyrroles 3a-d (FIG. 1):

5-15 g of the protected pyrrole 2a-d were added with 5 equiv. KOH in absolute dihydroxyethane (15-50 ml) heated to 180 ° C. After one hour the solution was allowed to cool, a little water (4-10 ml) was added and the pyrroles, 3a-d crystallized at -5 ° C. The white crystalline compounds were filtered off, washed twice with water and dried in a high vacuum.

Preparative and analytical data of the 2,5-disubstituted N-aminopyrroles: Compound 3a:

Yield 80.0%, C ₆ H, ιN ₂ , m.p .: 40-45 ° C, Η NMR (CDC1 ₃ ): δ 2.10 (s 6H methyl), 5.59 (s 2H pyrrole); MS: Ivf = 234.5 m / z.

Connection 3b:

Yield 95.4%, C ₁₀ H ₈ N ₂ , m.p .: 56-57 ° C, 1H NMR (CDCI ₃ ): δ 1.25 (d 12 H methyl), 3.05 (m 2H CH (CH ₃ ) ₂ ), 5.73 (2H pyrrole); MS: M ⁺ = 166.5 m / z.

Connection 3c:

Yield 89.6%, C ₁₂ H ₂ 2N ₂ , m.p .: 66-68 ° C, Η NMR (CDCI ₃ ): δ 1.38 (s 18 H t-butyl), 4.40 (s 2H NH ₂ ), 5.73 (s 2H pyrrole); MS: M ⁺ = 194.5 m / z.

Compound 3d: yield 89.5%, -C ₆ Hι ₄ N ₂ , mp .: 217-219 ° C,, NMR (CDCI ₃ ): δ 4.69 (s 2H NH ₂ ), 6.18 (s 2H pyrrole ), 7.1-7.6 (m 15 H phenyl); MS: M ⁺ = 194.5 m / z.

B Synthesis of asymmetrically and symmetrically substituted

Diimine Ligands 4, 5, 6, 10 Example 3:

Synthesis of the symmetrically substituted diimine ligands 4,5 (FIG. 2)

1-2 g of an aminopyrrole 3a or 3b and 0.5 equiv. of a diketone (acenaphtenquinone or 2,3-butanedione) were stirred for 12 hours in a 2: 1 mixture of methanol / formic acid (total 5 ml). The solutions turned light yellow or red after a short time. The reaction solutions were slowly diluted with a little water, further stirred for 1 hour and then filtered off. The filtrate was washed with water and then dried in a high vacuum.

Preparative and analytical data of the symmetrically substituted diimine ligands 4a, b and 5a, b:

Connection 4a:

Yield 82%, Cι ₆ H ₂₂ N ₄ , mp: 108-112 ° C, Η NMR (CDC1 ₃ ): δ 2.10 (s 6H methylpyrrole), 2.23 (s 6H methyl diketone), 5, 94 (s 2H pyrrole); MS: M ⁺ = 270 m / z.

Connection 4b:

Yield 74.5%, C ₂₄ H ₃₈ N ₄ , m.p .: 101-104 ° C, Η NMR (CDC1 ₃ ): δ 1.18 (d 6H CH (CHj), 2.16 (s 6H methyl diketone ), 2.59 (m 4H CH (CH ₃ ), 5.94 (s 2H pyrrole); MS: M ⁺ = 382.5 m / z.

Compound 5a:

Yield 72.6%, C ₂ H ₂₂ N ₄ , Η NMR (CDCI ₃ ): δ 1.98 (s 12H methylpyrrole), 5.93 (s 2H pyrrole), 6.67 (d 2H) 7.41 ( t 2H), 7.92 (d 2H) acenaphtenquinone; MS: M ⁺ - 366.5 m / z. The synthesis of compound 5b was carried out almost analogously to the conditions described above. Only a solvent mixture of methanol / formic acid 1: 3 was used for the reaction and heated under reflux for 12 hours.

Compound 5b: yield 74.8%, C ₃₂ H ₃₈ N ₄ , m.p .: 254-256 ° C, Η NMR (CDCI ₃ ): δ 4.13 (dxd 24H CH (CH ₃ ), 2.75 (m 4H CH (CH ₃ ), 6.06 (s 2H pyrrole), 6.67 (d 2H) 7.54 (t 2H) 7.98 (d 2H) acenaphtenquinone; MS: M ⁺ - 382.5 m / z ,

Example 4:

Synthesis of asymmetrically substituted diimine ligands 6a, b (Figure 2) The synthesis of the asymmetrically substituted ligands was carried out in two steps. First, an amine component was condensed under acidic conditions, and then the second component under anhydrous conditions with trimethylaluminium as auxiliary reagent. 100-300 mg of the aminopyrroles 3b and d were treated with an equiv. Acenaphtenquinone in methanol / formic acid 1: 3 heated under reflux for 12 hours. The solvent was then removed in a high vacuum, so that the monoimine was completely acid-free. All further reaction steps were carried out under argon with absolute solvents. A solution with activated 2,6-diisopropylaniline was prepared by adding 15.0 ml of 2,6-diisopropylaniline in abs. Toluene and 40.0 ml 2.0 M trimethyl aluminum in toluene were gently stirred at room temperature. The solution was heated to 60 ° C. until gas evolution ceased. After cooling, a total volume of 100 ml was adjusted with toluene; the resulting standard solution was 0.80 M and was kept in the refrigerator. Two equiv. this solution was then added to the monoimines prepared above. The red solutions were stirred at 50 ° C for 5 hours. After cooling, it was carefully hydrolyzed with 30% sodium hydroxide solution. The aqueous phase was extracted twice with methylene chloride, the organic phase was dried with sodium sulfate and the solvent was removed under reduced pressure. The crude products were recrystallized in a chloroform / hexane mixture for purification.

Preparative and analytical data of the asymmetrically substituted diimine ligands 6a, b: Compound 6a:

Yield 60.1%, C ₃ H ₃₉ N ₃ , m.p .: 274-276 ° C, Η NMR (CDC1 ₃ ): δ 0.94 0.96 1.02 1.05 1.19 1.21 1, 22 1.23 (2xdxd 24H CH (CHj) phenyl and pyrrole), 2.76 2.97 (m 4H CH (CH ₃ ) phenyl and pyrrole), 6.04 (s 2H pyrrole), 6.57 6.59 6.60 6.63 (2xd 2H) 7.34 7.50 (2xt 2H) 7.86 7.89 7.94 7.96 (2xd 2H) acenaphtenquinone; MS: M ^* = 489.5 m / z.

Connection 6b:

Yield 65.1%, C ₄₀ H ₃₅ N ₃ , m.p .: 260-270 ° C, Η NMR (CDC1 ₃ ): δ 0.85 0.88 1.29 1.31 (dxd 24H CH (CHj) pyrrole), 2.95 (rn 4H CH (CH ₃ ) pyrrole), 6.69 (s 2H Pyrrole), 6.48 6.50 6.69 6.72 (2xd 2H), 7.44 7.30 (2xt 2H) 7.71 7.74 7.80 7.83 (2xd 2H) acenaphtenquinone, 7, 0-7.3 (m 10H diphenylpyrrole); MS: M ⁺ = 557.5 m / z.

Example 5: Synthesis of the symmetrically substituted diimine ligands10 (FIG. 3)

To synthesize compound 10 b, c (FIG. 3), the amino components (2-5 g of N-aminopiperidine and N-aminocarbazole) were dissolved in 20 ml of absolute toluene and an equiv under an argon atmosphere. Trimethyl aluminum (2.0 M solution in toluene) added. These solutions were heated under reflux for 3 hours (10b) or heated to 60 ° C. (10c) until the evolution of gas ceased. After cooling to room temperature, 0.25 equiv. Acenaphtenquinone added, the solutions immediately turning red. After 4 hours at 50 ° C., 100 ml of ether and 200 ml of 20% aqueous KOH solution were carefully added, shaken well and the organic phases were separated off. These were then dried with sodium sulfate and the solvent removed under reduced pressure. The red residues were crystallized from toluene / hexane.

Connection 10b:

Yield: 58.7%, C22H ₂₆ N ₄ , 1H NMR (CDC1 ₃ ): δ 1.4-1.7 (m 12H), 3.4 (t 6H piperidine -NCH ₂ -), 7.62 (m 2H) 8.22 (d 2H) 8.26 (d 2H) acenaphtenquinone; MS: M ⁺ = 346 m / z. Compound 10c:

Yield: 47.6%, C ₃₆ H ₂₂ N ₄ , Η NMR (CDC1 ₃ ): 6.8-7.5 (m 14H), 7.7-8.2 (m 4H), 8.2-8.4 (m 4H); MS: M ⁺ = 510.5 m / z.

C Synthesis of the nickel complexes

Example 6: General procedure for the synthesis of the nickel bromide complexes (FIGS. 2, 3)

50-200 mg of compounds 4a. 5a, 5b, 6a, 6b and 10b were made under argon with an equiv. NiBr2 * DME or NiCl2 * DME in absolute methylene chloride (20-80 ml) stirred for at least 15 hours. The solutions turned brown to black after only a few minutes and the complex that formed mostly precipitated out as a brown precipitate. The solvent was in a high vacuum removed, the brown residue finely powdered and digested several times with absolute hexane (30 ml). The hexane phase could be easily removed by decanting; the products 7a, 8a, 9b, 9a and 11b were dried in a high vacuum. Nickel complex 8b could not be isolated in the manner described above, but had to be used with the reaction solution in the polymerization experiments.

Preparative and analytical data of the nickel complexes:

Compound 7a: yield 58.3%, -C H ₂₂ N Br ₂ Ni, brown powder.

Compound 8a:

Yield 60.1%, C ₂₄ H ₂₂ N ₄ Br ₂ Ni, brown powder.

Compound 9a:

Yield 84.2%, C ₃ H ₃₉ N ₃ Br ₂ Ni, brown powder. Connection 9b:

Yield 44.6%, C ₄₀ H ₃ N ₃ Br ₂ Ni, brown powder.

Compound 11b: yield 66.6%, C ₂₂ H ₂₆ N ₄ Cl ₂ Ni, black powder, NMR (DMSO d ₆ ) paramagnetic δ 2.5 (s broad 4H), 2.75 (s broad 8H) 3.95 (s broad 8H), 8.6-9.2 (m 6H) acenaphtenquinone; MS: M ⁺ = 476.5 m / z. For chemical figures, see Appendix 1

D polymerisation experiments

Example 7:

Homopolymerization of ethene with isolated catalysts

250 ml of dry toluene are placed in a 500 ml four-necked glass flask. After the addition of 28.9 mmol of MAO (methylaluminoxane) and 289 μmol of catalyst 9a, ethene is blown through the solution at a throughput of 40 l / h without pressure. A polymerization temperature of 50-55 ° C is set. After 4.5 hours, the polymerization is stopped by adding HCl / MeOH. The polymerization mixture is separated in a separatory funnel. The toluene phase is washed with H ₂ O and dried. After filtration through a column filled with aluminum oxide (neutral), the polymer is separated off by means of the evaporation of the toluene (75 ° C., 0.1 mbar, 3 h). The polymerization experiments with the catalysts 7a, 8a and 9b were carried out analogously. Specific information can be found in Table 1.

The polymerization results and structural analyzes of the polymers are summarized in Table 2.

Example 8: Homopolymerization of ethene with a catalyst prepared "in situ"

250 ml of toluene are placed in a 500 ml four-necked flask. After combining 14.3 mmol of MAO (methylaluminoxane) and 143 μml of a mixture of ligand 5b and NiBr ₂ -DME complex stirred in methylene chloride at 22 ° C. overnight, ethene is depressurized through the solution at a throughput of 40 l / h blown through. The polymerization temperature is set at 50-55 ° C. After 4.5 hours, the polymerization is stopped by adding HCl / MeOH.

The polymerization mixture is separated in a separatory funnel. The toluene phase is washed with H ₂ O and dried. After filtration through a column filled with aluminum oxide (neutral), the polymer is separated by evaporation of the toluene (75 ° C., 0.1 mbar, 3 h).

The polymerization results and structural analysis are summarized in Table 2.

Example 9: Homopolymerization of ethene using [((Ar) N = C (An) -C (An) = N (Ar)) NiBr ₂ ] (Ar: 2,6-diisopropylphenyl, An: acenaphthene) as catalyst (Comparative Example 1 ) (M. Brookhart et al., J. Am. Chem. Soc. 1995, 117, 6415-6415)

250 ml of dry toluene are placed in a 500 ml four-necked glass flask. After the addition of 16 mmol MAO and 160 μmol [((Ar) N = C (An) - C (An) = N (Ar)) NiBr], ethene is blown through the solution at a throughput of 40 l / h without pressure. The polymerization temperature is set at 50-55 ° C. After 4.5 h, the polymerization is carried out by adding HCl / MeOH canceled. The mixture is separated in the separating funnel. The toluene phase is washed with H2O and dried. After filtration through a column filled with aluminum oxide (neutral), the polymer is separated off by means of the evaporation of the toluene (75 ° C., 0.1 mbar, 3 h). The polymerization results and structural analysis are summarized in Table 2.

The following figures show:

Figure 1: Synthesis of 2,5-disubstituted N-aminopyrroles

Figure 2: Synthesis of ligands 4a, b; 5a, b; 6a, b and the nickel complexes 7a; 8a, b; 9a, b

Figure 3: Synthesis of the ligands 1 Ob, c and the nickel complex 11b

¹ Brookhart catalyst

² Catalyst was used “in situ” without working up

Brookhart catalyst ² catalyst was used "in situ" without working up

3 temperature of a sample cooled rapidly from 160 ° C; Weight approx. 13 mg; Heating rate 20 ° C / min.

Claims

1, 2-diimines of the general formula (I)

in which the symbols have the following meaning

R ¹ radicals of the general formula NR ⁵ R ⁶ ,

R ² radicals of the general formula NR ⁵ R ⁶ or alkyl, aryl or cycloalkyl radicals,

R ⁵ and R ⁶ together with the N atom form a 5-, 6- or 7- membered ring in which one or more of the -CH or -CH ₂ groups can be replaced by suitable heteroatom groups, which is saturated, unsaturated and unsubstituted, substituted or fused with further carbacyclic or heterocarbacyclic 5- or 6-membered rings which in turn can be saturated or unsaturated and substituted or unsubstituted, and

R ³ , R ⁴ independently of one another are H, alkyl, cycloalkyl or

Aryl residues, or

R ³ and R ⁴ together form a cyclic radical, so that, including the two imine carbon atoms, a carbacyclic or heterocarbacyclic 5- to 8-membered ring is formed which is saturated or unsaturated and unsubstituted, substituted or with other carbacyclic or heterocarbacyclic 5 - or 6-membered rings, which in turn can be saturated or unsaturated and substituted or unsubstituted, can be fused. Compounds according to claim 1, characterized in that the residues of the general formula NR ⁵ R ⁶ pyrrole or residues derived from pyrrole, in which one or more -CH groups in the pyrrole ring can be replaced by nitrogen, are unsubstituted, substituted or with further carbacyclic or heterocarbacyclic 5- or 6-membered rings, which in turn can be saturated or unsaturated and substituted or unsubstituted, fused.

Compounds according to claim 2, characterized in that the pyrrole or pyrrole-derived residues in the 2- and 5-position with Ci to C ₆ - alkyl groups, linear, branched and can be substituted with heteroatoms and / or aryl unsubstituted or in turn substituted with C _\ - to C ₆ -alkyl groups, which may be heteroatom-substituted.

Compounds according to Claim 3, characterized in that they have one of the general formulas (lai), (Ibj), (Ici) or (Idi):

wherein R ⁹ , R ¹⁰ , R ^U and R ¹² independently of one another CI- to C6-

Mean alkyl radicals, and ni T) i ι u (H, alkyl, cycloalkyl or aryl belong to). A process for the preparation of symmetrical compounds of the general formula (I) according to Claim 1, in which R ¹ = R ² , by reacting compounds of the general formula (II)

H ₂ N- NR5R6 (π) where

R ⁵ and R ⁶ together with the N atom are a 5-, 6- or 7-membered

Form a ring in which one or more of the -CH- or -CH ₂ -

Groups can be replaced by suitable heteroatom groups, which are saturated, unsaturated and unsubstituted, substituted or fused with other carbacyclic or heterocarbacyclic 5- or 6-membered rings, which in turn can be saturated or unsaturated and substituted or unsubstituted, with 1.2 Diketo compounds of the general formula (III)

wherein R ³ , R ^{4 are} independently H, alkyl, cycloalkyl or

Aryl residues, or

R ³ and R ⁴ together form a cyclic radical, so that, including the two carbonyl carbon atoms, a carbacyclic or heterocarbacyclic 5- to 8-membered ring is formed which is saturated or unsaturated and unsubstituted, substituted or with other carbacyclic or heterocarbacyclic 5 - or 6-membered rings, which in turn can be saturated or unsaturated and substituted or unsubstituted, can be fused, in a one-step process under acidic reaction conditions in alcoholic solution or with aluminum trialkyl catalysis in an aprotic solvent in a ratio of the compound of general formula (II) to the compound of general formula (III) from 2: 0.7 to 1.3.

A process for the preparation of unsymmetrical compounds of the general formula (I) according to claim 1, wherein R ¹ ≠ R ² , in a two-stage process in which:

a) in a first stage compounds of the general formula (II)

H ₂ N-NR5R6 (H) wherein

R ⁵ and R ⁶ together with the N atom form a 5- or 6-membered ring in which one or more of the CH or CH groups can be replaced by suitable heteroatom groups, which are saturated, unsaturated and unsubstituted, substituted or with further carbacyclic or heterocarbacyclic 5- or 6-membered rings, which in turn can be saturated or unsaturated and substituted or unsubstituted, fused with 1, 2-diketo compounds of the general formula (III)

wherein R ³ , R ^{4 are} independently H, alkyl, cycloalkyl or

Aryl residues, or

R ³ and R ⁴ together form a cyclic radical, so that, including the two carbonyl

Carbon atoms, a carbacyclic or heterocarbacyclic 5- to 8-membered ring is formed, which is saturated or unsaturated and unsubstituted, substituted or with other carbacyclic or heterocarbacyclic 5- or 6-membered rings, which in turn can be saturated or unsaturated and substituted or unsubstituted, can be fused, in a ratio of the compounds of the general formula (II) to the compounds of the general formula (III) of 1: 0.8 to 1, 2 are reacted under acidic conditions in alcoholic solution to the corresponding monoimine and the solvent is then removed in vacuo, and b) the monoimine in a second stage with compounds of the general formula (II), which differ from the compounds used in stage a) of the general formula (II), or with compounds of the general formula (IV)

H ₂ N- NR7R8 (TV) wherein R ⁷ and R ^{8 are} independently alkyl, aryl or

Are cycloalkyl radicals, or with amines of the general formula (V)

R13 - NH ₂ (V) wherein

R ^{13 is} an alkyl, an aryl or a cycloalkyl radical in aprotic solution with aluminum trialkyl catalysis in a ratio of the monoimine to a compound of the general formula (II) or of the general formula (IV) or (V) of 1: 0.8 to 1, 2 is implemented.

7. Compounds of the general formula (VI),

where the symbols have the following meaning

R ¹ radicals of the general formula NR ⁵ R ⁶ ,

R ⁵ and R ⁶ together with the N atom form a 5-, 6- or 7- membered ring in which one or more of the -CH or -CH ₂ groups can be replaced by suitable heteroatom groups, which is saturated, unsaturated and unsubstituted, substituted or fused with further carbacyclic or heterocarbacyclic 5- or 6-membered rings, which in turn can be saturated or unsaturated and substituted or unsubstituted, and-

R ³ , R ⁴ independently of one another are H, alkyl, cycloalkyl or

Aryl residues, or

R ³ and R ⁴ together form a cyclic radical, so that, including the two imine carbon atoms, a carbacyclic or heterocarbacyclic 5- to 8-membered ring is formed which is saturated or unsaturated and unsubstituted, substituted or with other carbacyclic or heterocarbacyclic 5 - or 6-membered rings, which in turn can be saturated or unsaturated and substituted or unsubstituted, can be fused;

X is a halide or a Cj to C ₆ alkyl radical; n valency of the metal M.

8. A compound according to claim 7, characterized in that M = Pd or Ni and n = 2 or 3.

9. A process for the preparation of compounds of the general formula (VI) according to claim 7, by reacting corresponding compounds of the general formula (I) with transition metal salts of metals from group 8, 9 or 10 of the periodic table of the elements.

10. Use of compounds of the general formula (VI) according to

Claim 7 as catalysts in a process for the polymerization of unsaturated compounds.

11. A process for the preparation of polyolefins by polymerizing unsaturated compounds in the presence of an activator and a compound of the general formula (VI) according to claim 7 as a catalyst.

12. The method according to claim 11, characterized in that the catalyst is present in the polymerization homogeneously immobilized in solution or heterogeneously on a support.

13. The method according to claim 11 or 12, characterized in that

Methylaluminoxane or N, N-dimethylanilinium tetrakis (pentafluorophenyl) borate is used as an activator.

14. The method according to any one of claims 11 to 13, characterized in that an unsaturated compound or a combination of unsaturated compounds selected from ethylene, C ₃ - to C ₂ o-monoolefins, cycloolefins and propylene is used.

15. Polvolefm, producible in a method according to any one of claims 11 to

14th