WO2002049758A1

WO2002049758A1 - Compounds

Info

Publication number: WO2002049758A1
Application number: PCT/GB2001/005699
Authority: WO
Inventors: Mats Tilset; Ove Andell; Ajaib Dhindsa; Morten Froseth
Original assignee: Borealis Technology Oy
Priority date: 2000-12-20
Filing date: 2001-12-20
Publication date: 2002-06-27
Also published as: GB0031078D0; AU2002217285A1

Abstract

The present invention provides the use of certain complexes of a group 3 to 10 transition metal or a lanthanide (M) and a ligand of formula (I), wherein each group A, which may be the same or different, is an M-coordinating carbon or heteroatom or θq group, at least one group A being an M-coordinating carbene carbon, silicon, germanium or phosphorus (i.e. C:, Si:, Ge: or P:) which is a ring member of a 4- or 5- ring atom heterocycle; each L, which may be the same or different, is a bond or bridging group providing a 1 to 5 atom chain between the groups it connects; R is a hydrogen atom or a C¿1-20? hydrocarbyl group optionally attached by a silicon atom or a Si-O- group; each R*, which may be the same or different, is a group R or together both R* are a bond whereby to form an 8 to 22 ring atom macrocycle; n is 0 or 1; m is 0 or 1; p is 0, 1 or 2; and q is an integer having a value of 2 to 6; as catalysts, procatalysts, or catalyst precursors.

Description

Compounds

This invention relates to a novel class of polymerization catalysts, in particular organometallic olefin polymerization catalysts, their use in polymerization and polymers prepared therewith.

It has long been known to use organometallic compounds, e.g. metallocenes, as olefin polymerization catalysts.

There is however a continuing search for new organometallic polymerization catalysts.

We have now found that certain carbenes may complex transition metal or lanthanide ions to produce complexes which function as olefin polymerization catalysts.

Viewed from one aspect the invention provides the use of a complex of a group 3 to 10 transition metal or a lanthanide (M) and a ligand of formula I

R*-L[A-L]_πA-L[A-L]_pA-L-R* (I)

A-

A

L

(wherein each group A, which may be the same or different, is an M-coordinating carbon or heteroatom or η^q group, at least one group A being an M-coordinating carbene carbon, silicon, germanium or phosphorus (i.e.

C:, Si:, Ge : or P : ) which is a ring member of a 4- or 5- ring atom heterocycle; each L, which may be the same or different, is a bond or bridging group providing a 1 to 5 atom chain between the groups it connects;

R is a hydrogen atom or a C₁_₂₀ hydrocarbyl group optionally attached by a silicon atom or a Si-O- group; each R* , which may be the same or different, is a group R or together both R* are a bond whereby to form an 8 to 22 ring atom macrocycle; n is 0 or 1; i is 0 or 1; p is 0, 1 or 2; and q is an integer having a value of 2 to 6; with the provisos that where n, m and p are 0 and each

R* is a group R then one A group is a carbene silicon, germanium or phosphorus atom and the other A group is a carbene carbon, silicon or germanium atom, a nitrogen atom or a η^q group or one A group is a carbene carbon atom and the other A group is a carbene carbon, silicon, germanium or phosphorus ^' atom, a ring nitrogen in a 5 or 6 membered heterocycle, an open chain η^q group, or less preferably an N^θ, and that where the sum of n, m and p is zero or 1, each R* is a group R, one A group is a carbene carbon atom and M is a group 6 transition metal then another A group is a carbene silicon, germanium or phosphorus atom, a ring nitrogen in a 5 or 6-membered heterocycle, an open chain η^q group or, less preferably, an N^θ) as a catalyst, procatalyst, or catalyst precursor, especially as a catalyst or procatalyst for olefin polymerization. As used herein, the term "M-coordinating atom/group" is intended to cover those atoms and groups which actually co-ordinate to the metal in a complex as well as those atoms or groups which are capable of doing so. The ligand of formula I, especially where it contains 4, 5 or 6 A groups, may of course complex more than one metal. Such further metals may be group 3 to 10 transition metals or lanthanides (i.e. M metals) or alternatively they may be metals from other groups . The ligand of formula I is thus a linear, branched or macrocyclic entity having two, three, four, five or six M-coordinating atoms or groups, preferably two, three or four such groups, especially two or three of such groups . The ligand backbone may carry pendant or fused substituents R¹, e.g. to present M-coordinating carbene carbon, silicon, germanium or phosphorus atoms in the 2-position of a 1,3-attached 4- or 5-membered heterocyclic ring, e.g. an Arduengo carbene or the silicon or germanium analogues, a 1,3- diphosphacyclobutane-2,4-diyl-2-ylidenide or a cyclic phosphinophosphonium (e.g. a 1, 3-diaza-2-phospha- cyclopentane) , or to present an M-coordinating nitrogen in the 2-position of a 1,3-attached 5- or 6-membered heterocycle. Such fused R¹ substituents may themselves carry further pendant or fused substituents R². In general R¹ and R² will be C^_o hydrocarbyl groups (e.g. linear, branched, mono and polycyclic groups) , optionally attached or interrupted by heteroatoms selected from P, N, Si, 0 and S atoms, e.g. one of two heteroatoms, preferably N, 0 or S . Fused substituents will generally be such as to produce 5 to 7 ring membered homo or heterocyclic groups.

It is especially preferred that at least one A group be in an Arduengo-type carbene or a silicon or germanium analog, of formula II

R3

-X x- (II) Ύ

where Y is C:, Si: or Ge:; each X is N or P;

Z is N or CR³; and each R³ independently is hydrogen or a group R² as defined above, or in a 1, 3-diphosphacyclobutane-2, 4-diyl-2-ylidenide, Examples of groups of formula II include

Further Arduengo carbenes are disclosed in

WO00/78826 which is incorporated herein by reference.

Particularly preferably the ligand of formula I is of formula la

R*-L" [A²-L"]_nA¹-L" [A²-L" ] _pA²-L" -R* (la)

where A¹ is a group of formula II; each A² independently is a group of formula II, or an M- coordinating η², η⁵, N or N^θ; and each L" independently is a bridging group providing a 1,

2, 3 or 4 atom chain, preferably a carbon atom chain, between the groups it connects.

Where a group A is an η^q group, this may be an open chain or cyclic group and may carry pendant or fused R¹ groups. Fused R¹ groups in turn may carry pendant or fused R² groups . Examples of cyclic η⁵ groups include homo and heterocyclic cyclopentadienyl groups, indenyl groups, tetrahydroindenyl groups, fluorenyl groups, etc. Many such groups are known for use as ligands in metallocene complexes. Open chain η^q groups include carbon and/or nitrogen containing η², η³, η⁴ and η^s groups, e.g.

R¹ R¹ R¹ R¹ R¹ R¹

I I I 1 I I - C = C - - C =C - C = C-

etc. (where R¹ is as defined above) . Again such groups are known from the patent literature relating to olefin polymerization catalysts.

Thus examples of the skeleton structures (i.e. showing only the groups A, the intervening backbone atoms and any ring in which A is disposed) of the ligands of formula I include

and the C₂N₂Si , C₂N₂Ge , C₂N₃ and C₃P₂ equivalents , i . e . where the carbene C₃N₂ ring (s) is (are) replaced by a C₂N₂Si , etc . , ring .

The L bridges are either bonds or up to 5 atom chains, generally the bridging atoms being selected from C, N and P and preferably being N or P if adjacent a carbene carbon, silicon or germanium A, and C if adjacent another A group .

The ligands of formula I may be prepared by conventional techniques, e.g. by coupling together preformed groups containing the M-coordinating A groups. Thus reagents Lv-L ' -A-L ' -Lv and Lx-L' -A-L ' -Lx may be reacted to produce Lv-L'A-L-A-L' -Lx or Lx-L ' -A-L-A-L-A- L'-Lx (where Lv and Lx are interactive/leaving groups (e.g. H and halogen) or non-interactive groups, at least one LxLv pair being interactive, and L' are groups L or groups which join together to form a group L on Lv Lx interaction) . One or both of the reagents may first be metallated to promote the ligand forming reaction, especially where the reaction involves macrocycle formation. Macrocyclic ligand construction has been discussed at length in the patent literature of the 1980s and 1990s relating to magnetic resonance imaging contrast agents (see in particular the patent publications of Nycomed, Salutar, Schering, Bracco and Mallinckrodt) .

One particularly preferred set of ligands of formula I is the ligands of formula III

where R⁴ is H or - (CR⁵ ₂) _SNR^S ₂, - (CR⁵ ₂) _SN^ΘR^S, or - (CR^Ξ ₂) _tCR⁵=NR⁵, at least one R⁴ being other than H; s is 1, 2 or 3 , especially 2; t is 1 or 2; each R⁵ is hydrogen or a group R¹ as hereinbefore defined;

X is as hereinbefore defined; and Y' is a carbene carbon or silicon atom.

The construction of carbene cores of ligands of formula III is discussed in WO00/78826 and the references therein, the construction of silylene cores is discussed in Organometallics 19_.: 4726-4732 (2000) and the references therein, the construction of 1,3- diphosphacyclobutane-2 , 4-diyl-2-ylidenides is discussed in Niecke et al . Angew. Chem. Int. Ed. 20_.: 3031 (1999), and the construction of phosphinophosphonium cores is described in Abrams et al . , Organometallics 19: 4944- 4956 (2000) .

In the ligands of formula III, at least one of the nitrogen attached R⁵ groups in each non-hydrogen R⁴ is preferably a bulky hydrocarbyl group, e.g. containing 4 to 12 carbon atoms . The CR⁵ ₂ and CR^S groups are preferably CH₂ or CH groups respectively. Each X is preferably N and Z is preferably CR³. R³ is preferably hydrogen .

Hence a particularly preferred ligand of the invention is of formula

R*'—NT N—L₁—N—R* \\_/

wherein R* ' is methyl or 2 , 4 , 6-trimethylphenyl, R* ' ' is 2, 6-diisopropylphenyl or 2 , 4, 6-triisopropylphenyl, and L¹ is a 2 to 4 carbon atom linking group, the link to the non-ring nitrogen being via an i ino bond.

The metal M in the catalysts and procatalysts used according to the invention is a group 3 to 10 transition metal or a lanthanide, especially a transition metal, particularly Ti, Zr, Hf, V, Cr, Mo, W, Fe, Co, Ni, Rh or Pd, especially Ti, Zr, Hf, Cr, Fe, Co, Ni or Pd. The catalysts or procatalysts may be prepared by metallating a ligand of formula I or transmetallating a metal complex of a ligand of formula I with the desired metal. Where the reaction is a transmetallation, the displaced metal may be another metal M or a non-M metal, e.g. a group 11 or 12 transition metal (e.g. silver) . Viewed from a further aspect the invention provides the use of a complex of a group 3 to 10 transition metal or a lanthanide with a macrocyclic (i.e. 8 to 22 ring atom homo or heterocyclic) carbene chelant as an olefin polymerization catalyst or procatalyst. Viewed from a yet still further aspect the invention provides the use of a complex of a group 3 to 10 transition metal or lanthanide with a ligand of formula IV

(wherein X, Y', Z and R³ are as hereinbefore defined; and each R⁶, which may be the same or different, is hydrogen or a group R¹ (as hereinbefore defined) or both R^s groups together form a group -CR³=CR³-, with the proviso that where R^s is hydrogen or a pendant R¹ group then either Y' is other than carbon or at least one X or Z is P) as an olefin polymerization catalyst or procatalyst.

In the ligands any hydrocarbyl group may for example be an alkyl, alkenyl, aryl, aralkyl, alkaryl, alkarylalkyl, cycloalkyl, cycloalkenyl, cycloalkylalkyl, etc. group. Alkyl, alkylene, alkenyl, and alkenylene moieties, including cyclic moieties, preferably contain up to 8 carbons; aryl and arylene moieties preferably contain 6 to 10 carbons. Alkylsilyl and alkylsilyloxy moieties preferably contain C^ , alkyl groups, e.g. tBu(Me)₂, (iPr)₃ and CH₂=CH(CH₂)₆ (Me)₂. The compounds of the invention wherein M is a group 3 to 8 transition metal or a lanthanide are olefin polymerization catalysts or procatalysts, i.e. compounds which become catalytically active on reaction with a co- catalyst or catalyst activator (e.g. an ionic or nonionic compound such as a boron compound or an organoaluminium compound, e.g. an alumoxane) , generally to replace or remove dative or σ- ligands or non- coordinating anions. Such catalysts and procatalysts are generally referred to herein simply as catalysts .

The compounds of formula I, in particular those wherein M is a group 9 or 10 transition metal (e.g. Ag) , may also be catalyst (or procatalyst) precursors which may be converted into catalysts (or procatalysts) by transmetallation with group 3 to 8 transition metals or lanthanides .

Thus viewed from a further aspect the invention also provides the use of a compound according to the invention wherein M is a group 3 to 8 transition metal or lanthanide as a catalyst in olefin polymerization.

Viewed from a still further aspect the invention also provides the use of a compound according to the invention for the manufacture by transmetallation of an olefin polymerization catalyst compound according to the invention wherein M is a group 3 to 8 transition metal or lanthanide .

Viewed from another aspect the invention provides an olefin polymerization catalyst system comprising a compound according to the invention wherein M is a group 3 to 8 transition metal or lanthanide or the reaction product thereof with a co-catalyst, optionally disposed within a porous particulate carrier, e.g. silica.

Viewed from still another aspect the invention provides an olefin polymerization catalyst system comprising (I) a compound according to the invention wherein M is a group 3 to 8 transition metal or lanthanide, optionally disposed within a porous particulate carrier, and (II) a co-catalyst, e.g. an alumoxane .

Viewed from a further aspect the invention also provides a process for olefin polymerization which process comprises polymerizing an α-olefin monomer, optionally together with at least one comonomer copolymerizable therewith, wherein as a catalyst is used a catalyst system according to the invention.

Viewed from another aspect the invention provides the use of a catalyst system according to the invention in olefin polymerization.

Viewed from another aspect the invention provides a polyolefin obtainable by olefin polymerization according to the invention, optionally followed by formulation (e.g. with additives such as stabilizers, nucleating agents, colors, further polymers, etc) and/or forming (e.g. moulding, blowing, extruding, casting, etc, for example into sheets, films, fibres, tubes, moulded forms, etc) . Viewed from a further aspect the invention provides a process for the preparation of a compound according to the invention, said process comprising at least one of the following steps:

(A) metallating a ligand of formula I or IV with a transition metal or lanthanide;

(B) transmetallating a metal complex of a ligand of formula I or IV with a transition metal or lanthanide; and

(C) displacing one or more ligands or anions in a transition metal or lanthanide complex of a ligand of formula I or IV by one or more different ligands or anions .

Viewed from a still further aspect the invention provides a ligand of formula I or IV or a salt or complex thereof.

The catalyst compounds or combinations according to the invention are preferably used in heterogeneous, i.e. solid or semi-solid, form. Heterogeneous catalyst particles may be produced by precipitation, agglomeration, impregnation of a support material, precipitation within a support matrix, precipitation of a support matrix from a solution or dispersion of the catalyst compound or combination, polymerization of a monomer to produce a polymeric or oligomeric matrix containing the catalyst compound or combination, prepolymerization using heterogeneous catalyst, etc. The catalyst used may be one or more catalyst or procatalysts according to the invention, optionally together with further catalysts or procatalysts (e.g. transition metal or lanthanide carbene complexes, metallocenes, Ziegler Natta catalysts, chromium or vanadium catalysts) optionally together with or following reaction with one or more co-catalysts or catalyst activators.

If desired, the catalysts, procatalysts and catalyst systems according to the invention may be used together with catalyst poison scavengers.

As mentioned above, the catalysts of the invention will generally be used as part of a catalyst system which also includes an ionic cocatalyst or catalyst activator, for example, an aluminoxane (e.g. methylaluminoxane (MAO) , hexaisobutylaluminoxane and tetraisobutylaluminoxane) or a boron compound (e.g. a fluoroboron compound such as triphenylpentafluoroboron or triphenylcarbenium tetraphenylpentafluoroborate ((C_εH₅)₃B⁺B-(C_sF_s)₄)) Alumoxanes are compounds with alternating aluminium and oxygen atoms generally compounds of formula

R*₂A1- (0-AlR*)_v-0-AlR*₂ or

R*A1- (0-AlR*)_v-0-AlR* ^ .0

where each R*, which may be the same or different, is a C_x_₁₀ alkyl group, and v is an integer having a value between 0 and 40) . These compounds may be prepared by reaction of an aluminium alkyl with water. The production and use of alumoxanes is described in the patent literature, especially the patent applications of Texas Alkyls, Albemarle, Ethyl, Phillips, Akzo Nobel, Exxon, Idemitsu Kosan, Witco, BASF and Mitsui.

The metal in the catalyst or procatalyst complexes used according to the invention may also be coordinated by hydrogen atoms, hydrocarbyl σ-ligands (e.g.optionally substituted C^₁₂ hydrocarbyl groups, such as C^ alkyl, alkenyl or alkynyl groups optionally substituted by fluorine and/or aryl (e.g.phenyl) groups), by silane groups (e.g.Si (CH₃)₃) , by halogen atoms (e.g. chlorine) , by C^ hydrocarbylheteroatom groups, by tri-C^ _shydrocarbylsilyl groups, by bridged bis-σ-liganding groups, by amine (e.g.N(CH₃) ₂) or imine (e.g.N=C or N=P groups, e.g. (iPr)₃P=N) groups, or by other σ-, η- or η/σ-ligands known for use in metallocene catalysts. Likewise the complex may include counterions which do not coordinate the metal .

By a σ-ligand moiety is meant a group bonded to the metal at one or more places via a single atom, e.g.a hydrogen, halogen, silicon, carbon, oxygen, sulphur or nitrogen atom.

Examples of σ-ligands include halogenides (e.g. chloride and fluoride) , hydrogen, triCj.i_a hydrocarbyl-silyl or -siloxy (e.g. trimethylsilyl) , triC^_s hydrocarbylphosphi ido (e.g. triisopropylphosphimido) , ^c _ι-i₂ hydrocarbyl or hydrocarbyloxy (e.g. methyl, ethyl, phenyl, benzyl and methoxy) , diC_α_₆ hydrocarbylamido (e.g. dimethylamido and diethylamido) , and

5 to 7 ring membered heterocyclyl (e.g.pyrrolyl, furanyl and pyrrolidinyl) . Preferable σ ligands include halogens, alkyls, or chloro-amido groups. σ-ligands other than chlorine may be introduced by displacement of chlorine from a liganded metal chloride by reaction with appropriate nucleophilic reagent (e.g. methyl lithium or methylmagnesium chloride) or using, instead of a metal halide, a reagent such as tetrakisdimethylamidotitanium or metal compounds with mixed chloro and dimethylamido ligands .

As mentioned above, the olefin polymerisation catalyst system of the invention comprises (i) a procatalyst formed from a metallated ligand and (ii) a co-catalyst (e.g. an aluminium alkyl compound) or the reaction product thereof. While the aluminium alkyl compound may be an aluminium trialkyl (e .g.triethylaluminium (TEA)) or an aluminium dialkyl halide (e.g. diethyl aluminium chloride (DEAC) ) , it is preferably an alumoxane, particularly an alumoxane other than MAO, most preferably an isobutylalumoxane, e.g.TIBAO (tetraisobutylalumoxane) or HIBAO (hexaisobutylalumoxane) . Alternatively however the alkylated (e.g.methylated) procatalysts of the invention may be used with other cocatalysts, e.g.boron compounds such as B(C₆F_S)₃, C_SH_SN(CH₃)₂H:B(C_SF₅)₄, (C₆H₅) ₂C :B (C₆F_S) ₄ or Ni(CN)₄[B(C₆F₅)₃]₄ ²-. The procatalyst and cocatalyst may be introduced into the polymerization reactor separately or together or, more preferably they are pre-reacted and their reaction product is introduced into the polymerization reactor. If desired the procatalyst, procatalyst/cocatalyst mixture or a procatalyst/cocatalyst reaction product may be used in unsupported form or it may be precipitated and used as such. However the procatalyst or its reaction product with the cocatalyst is preferably introduced into the polymerization reactor in supported form, e.g. impregnated into a porous particulate support. The particulate support material used is preferably an organic or inorganic material, e.g. a polymer (such as for example polyethylene, polypropylene, an ethylene- propylene copolymer, another polyolefin or polystyrene or a combination thereof) . Such polymeric supports may be formed by precipitating a polymer or by a prepolymerization, e.g. of monomers used in the polymerization for which the catalyst is intended. However, the support is especially preferably a metal or pseudo metal oxide such as silica, alumina or zirconia or a mixed oxide such as silica-alumina, in particular silica, alumina or silica-alumina. Particularly preferably, the support material is acidic, e.g. having an acidity greater than or equal to silica, more preferably greater than or equal to silica-alumina and even more preferably greater than or equal to alumina. The acidity of the support material can be studied and compared using the TPD (temperature programmed desorption of gas) method. Generally the gas used will be ammonia. The more acidic the support, the higher will be its capacity to adsorb ammonia gas. After being saturated with ammonia, the sample of support material is heated in a controlled fashion and the quantity of ammonia desorbed is measured as a function of temperature . Especially preferably the support is a porous material so that the complex may be loaded into the pores of the support, e.g. using a process analogous to those described in W094/14856 (Mobil) , W095/12622 (Borealis) and W096/00243 (Exxon) . The particle size is not critical but is preferably in the range 5 to 200 μm, more preferably 20 to 80 μm.

Before loading, the particulate support material is preferably calcined, ie heat treated, preferably under a non-reactive gas such as nitrogen. This treatment is preferably at a temperature in excess of 100°C, more preferably 200°C or higher, e.g. 200-800°C, particularly about 300°C. The calcination treatment is preferably effected for several hours, e.g. 2 to 30 hours, more preferably about 10 hours .

The support may be treated with an alkylating agent before being loaded with the complex. Treatment with the alkylating agent may be effected using an alkylating agent in a gas or liquid phase, e.g. in an organic solvent for the alkylating agent . The alkylating agent may be any agent capable of introducing alkyl groups, preferably C^ alkyl groups and most especially preferably methyl groups. Such agents are well known in the field of synthetic organic chemistry. Preferably the alkylating agent is an organometallic compound, especially an organoaluminium compound (such as trimethylaluminium (TMA) , dimethyl aluminium chloride, triethylaluminium) or a compound such as methyl lithium, dimethyl magnesium, triethylboron, etc.

The quantity of alkylating agent used will depend upon the number of active sites on the surface of the carrier. Thus for example, for a silica support, surface hydroxyls are capable of reacting with the alkylating agent. In general, an excess of alkylating agent is preferably used with any unreacted alkylating agent subsequently being washed away.

Where an organoaluminium alkylating agent is used, this is preferably used in a quantity sufficient to provide a loading of at least 0.1 m ol Al/g carrier, especially at least 0.5 mmol Al/g, more especially at least 0.7 mmol Al/g, more preferably at least 1.4 mmol Al/g carrier, and still more preferably 2 to 3 mmol Al/g carrier. Where the surface area of the carrier is particularly high, lower aluminium loadings may be used.

Thus for example particularly preferred aluminium loadings with a surface area of 300-400 m²/g carrier may range from 0.5 to 3 mmol Al/g carrier while at surface areas of 700-800 m²/g carrier the particularly preferred range will be lower.

Following treatment of the support material with the alkylating agent, the support is preferably removed from the treatment fluid and any excess treatment fluid is allowed to drain off.

The optionally alkylated support material is loaded with the complex, preferably using a solution of the complex in an organic solvent therefor, e.g. as described in the patent publications referred to above.

Preferably, the volume of complex solution used is from 50 to 500% of the pore volume of the carrier, more especially preferably 80 to 120%. The concentration of complex in the solution used can vary from dilute to saturated depending on the amount of active sites that it is desired be loaded into the carrier pores.

The active metal (ie. the metal of the complex) is preferably loaded onto the support material at from 0.1 to 4%, preferably 0.5 to 3.0%, especially 1.0 to 2.0%, by weight metal relative to the dry weight of the support material.

After loading of the complex onto the support material, the loaded support may be recovered for use in olefin polymerization, e.g. by separation of any excess complex solution and if desired drying of the loaded support, optionally at elevated temperatures, e.g. 25 to 80°C. Alternatively, a cocatalyst, e.g. an alumoxane or an ionic catalyst activator (such as a boron or aluminium compound, especially a fluoroborate) may also be mixed with or loaded onto the catalyst support material. This may be done subsequently or more preferably simultaneously to loading of the procatalyst, for example by including the cocatalyst in the solution of the procatalyst or, by contacting the procatalyst loaded support material with a solution of the cocatalyst or catalyst activator, e.g. a solution in an organic solvent. Alternatively however any such further material may be added to the procatalyst loaded support material in the polymerization reactor or shortly before dosing of the catalyst material into the reactor.

In this regard, as an alternative to an alumoxane it may be preferred to use a fluoroborate catalyst activator, especially a B(C_SF_S)₃ or more especially a ^ΘB(C₆F_S)₄ compound, such as C_SH_SN (CH₃) ₂H :B (C₆F_S) ₄ or (C₆H_S)₃C:B (C_SF_S) ₄. Other borates of general formula (cation⁺)_a (borate^~)_b where a and b are positive numbers, may also be used.

Where such a cocatalyst or catalyst activator is used, it is preferably used in a mole ratio to the metal (M) of the complex of from 0.1:1 to 10000:1, especially 1:1 to 50:1, particularly 1:2 to 30:1. More particularly, where an alumoxane cocatalyst is used, then for an unsupported catalyst the aluminium:metal metal (M) molar ratio is conveniently 2:1 to 10000:1, preferably 50:1 to 1000:1. Where the catalyst is supported the Al:M molar ratio is conveniently 2:1 to 10000:1 preferably 50:1 to 400:1. Where a borane cocatalyst (catalyst activator) is used, the B:M molar ratio is conveniently 2:1 to 1:2, preferably 9:10 to

10:9, especially 1:1. When a neutral triarylboron type cocatalyst is used the B:M molar ratio is typically 1:2 to 500:1, however some aluminium alkyl would normally also be used. When using ionic tetraaryl borate compounds, it is preferred to use carbonium rather than ammonium counterions or to use B:M molar ratio below 1:1.

Where the further material is loaded onto the procatalyst loaded support material, the support may be recovered and if desired dried before use in olefin polymerization.

The catalysts, procatalysts and catalyst systems of the invention may be used for conventional olefin polymerization. They may also however be used in metathesis polymerization (e.g. ring opening metathesis polymerization - ROMP) e.g. of cyclic alkenes such as cyclooctene. ROMP is discussed for example in Weskamp dosing of the catalyst material into the reactor.

In this regard, as an alternative to an alumoxane it may be preferred to use a fluoroborate catalyst activator, especially a B(C_eF₅)₃ or more especially a ^ΘB(C₆F_S)₄ compound, such as C_SH_SN (CH₃) ₂H:B (C₆F₅) ₄ or (C₆H₅) ₃C:B (C₆F₅) ₄. Other borates of general formula (cation⁺)_a (borate^')_b where a and b are positive numbers, may also be used.

Where such a cocatalyst or catalyst activator is used, it is preferably used in a mole ratio to the metal (M) of the complex of from 0.1:1 to 10000:1, especially 1:1 to 50:1, particularly 1:2 to 30:1. More particularly, where an alumoxane cocatalyst is used, then for an unsupported catalyst the aluminium: metal metal (M) molar ratio is conveniently 2:1 to 10000:1, preferably 50:1 to 1000:1. Where the catalyst is supported the Al:M molar ratio is conveniently 2:1 to 10000:1 preferably 50:1 to 400:1. Where a borane cocatalyst (catalyst activator) is used, the B:M molar ratio is conveniently 2:1 to 1:2, preferably 9:10 to

Where the further material is loaded onto the procatalyst loaded support material, the support may be recovered and if desired dried before use in olefin polymerization .

The catalysts, procatalysts and catalyst systems of the invention may be used for conventional olefin polymerization. They may also however be used in metathesis polymerization (e.g. ring opening metathesis polymerization - ROMP) e.g. of cyclic alkenes such as cyclooctene . ROMP is discussed for example in Weskamp et al. Angew. Chem. Int. Ed. 38_.: 2416-2419 (1999), DE-A- 19815275, W097/34875 and W099/51344.

The olefin polymerized in the method of the invention is preferably ethylene or an alpha-olefin or a mixture of ethylene and an α-olefin or a mixture of alpha olefins, for example C₂.₂₀ olefins, e.g. ethylene, propene, n-but-1-ene, n-hex-1-ene, 4-methyl-pent-l-ene, n-oct-1-ene- etc. The olefins polymerized in the method of the invention may include any compound which includes unsaturated polymerizable groups. Thus for example unsaturated compounds, such as C₆.₂₀ olefins (including cyclic and polycyclic olefins (e.g. norbornene) ) , and polyenes, especially C₆.₂₀ dienes, may be included in a comonomer mixture with lower olefins, e.g. C₂_₅ α-olefins. Diolefins (ie. dienes) are suitably used for introducing long chain branching into the resultant polymer. Examples of such dienes include α,ω linear dienes such as 1, 5-hexadiene, 1, 6-heptadiene, 1,8- nonadiene, 1, 9-decadiene, etc. In general, where the polymer being produced is a homopolymer it will preferably be polyethylene or polypropylene. Where the polymer being produced is a copolymer it will likewise preferably be an ethylene or propylene copolymer with ethylene or propylene making up the major proportion (by number and more preferably by weight) of the monomer residues. Comonomers, such as C₄_₆ alkenes, will generally be incorporated to contribute to the mechanical strength of the polymer produc . Usually metal complex catalysts according to the invention yield relatively narrow molecular weight distribution polymers; however, if desired, the nature of the monomer/monomer mixture and the polymerization conditions may be changed during the polymerization process so as to produce a broad bimodal or multimodal molecular weight distribution (MWD) in the final polymer product . In such a broad MWD product , the higher molecular weight component contributes to the strength of the end product while the lower molecular weight component contributes to the processability of the product, e.g. enabling the product to be used in extrusion and blow moulding processes, for example for the preparation of tubes, pipes, containers, etc.

A multimodal MWD can be produced using a catalyst material with two or more different types of active polymerization sites, e.g. with one such site provided by the metal M on the support and further sites being provided by further catalysts, e.g. Ziegler catalysts, Phillips catalysts, metallocenes, etc. included in the catalyst material .

Polymerization in the method of the invention may be effected in one or more, e.g. 1, 2 or 3, polymerization reactors, using conventional polymerization techniques, e.g. gas phase, solution phase, slurry or bulk polymerization.

In general, a combination of slurry (or bulk) and at least one gas phase reactor is often preferred, particularly with the reactor order being slurry (or bulk) then one or more gas phase.

For slurry reactors, the reaction temperature will generally be in the range 60 to 110°C (e.g. 85-110°C) , the reactor pressure will generally be in the range 5 to 80 bar (e.g. 50-65 bar), and the residence time will generally be in the range 0.3 to 5 hours (e.g. 0.5 to 2 hours) . The diluent used will generally be an aliphatic hydrocarbon having a boiling point in the range -70 to +100°C. In such reactors, polymerization may if desired be effected under supercritical conditions.

For gas phase reactors, the reaction temperature used will generally be in the range 60 to 115 °C (e.g. 70 to 110°C) , the reactor pressure will generally be in the range 10 to 25 bar, and the residence time will generally be 1 to 8 hours. The gas used will commonly be a non-reactive gas such as nitrogen together with monomer (e.g. ethylene).

For solution phase reactors, the reaction temperature used will generally be in the range 130 to 270°C, the reactor pressure will generally be in the range 20 to 400 bar and the residence time will generally be in the range 0.1 to 1 hour. The solvent used will commonly be a hydrocarbon with a boiling point in the range 80-200°C.

Generally the quantity of catalyst used will depend upon the nature of the catalyst, the reactor types and conditions and the properties desired for the polymer product. Conventional catalyst quantities, such as described in the publications referred to herein, may be used. All publications referred to herein are hereby incorporated by reference.

The invention will now be described further with reference to the following non-limiting Examples:

EXAMPLES

General procedures. All experiments were performed under nitrogen atmosphere . Example 1 l-Chloro-2- (2, 6-diisopropylphenylimino) propane (1) .

Chloroacetone (2.00 g, 21.6 mmol) and 2,6- diisopropylaniline (10.0 g, 56.4 mmol) were dissolved in ether (50 mL) . The contents were cooled to 0 °C in an ice bath. TiCl₄ (2.06 g, 10.9 mmol) was slowly added to the contents with a syringe while vigorously stirring the mixture. The mixture was stirred for 1 h at 0 °C and then for 3 h at ambient temperature . The mixture was filtered and the solid residue was washed with ether (2x25 mL) . The ether solution was treated with 0.1 M aqueous NaOH (100 mL) . The ether layer was separated, washed with water, and dried with potassium carbonate. The solvent was evaporated and the product was stored under nitrogen at 4°C in a refrigerator. The product was purified by carefully distilling off aniline at low vacuum. The product was pure as judged by ¹H NMR. Yield 5.0 g (18%) . 7.5 g 2,6 diisopropyl aniline was recovered from the product mixture. ^XH NMR: (CDC1₃, 200 MHz, 25°C) 57.09 (m, 3H, aryl-ff) , 4.27 (s, 2H, CH₂) , 2.69 (septet, J^" = 6.9 Hz, 2H, CHMe₂) , 1.81 (s, 3H, MeC=N) , 1.12 (d, J = 6.9 Hz, 12H, CH e₂) . "C^H} NMR (CDC1₃, 50 MHz, 25°C) δ 166.2 (C=N-C) , 144.7 (C-N=C) , 136.1 (o-aryl-C) , 124.0 (p-aryl-C) , 124.0 (p-aryl-C) , 123.0 (m-aryl-C) , 49.14 (CH₂C1) , 27.85 (C(CH₃)₂), 23.26 and 23.00 (C(CH₃)₂), 17.90 (CH₃) . MS (El): m/z 251 (M⁺) , 202 (M⁺-CH₂C1) .

Example 2 l-Chloro-2- (2,4, 6 -trimethylphenylimino) ropane (2).

To an ether solution of 2 , , 6-trimethylaniline (9 . 6 g, 0.071 mol) was added chloroacetone (2.8 mL, 0.035 mol) . After 5 min of stirring the solution was cooled to 0 °C, and TiCl₄ (2 mL, 0.018 mol) was added dropwise. After complete addition the mixture was heated to ambient temperature and stirred for 2 h. The mixture was filtered into an aqueous NaOH solution (1 M) . The product was extracted with 3x25 mL of ether and dried with K₂C0₃. Removal of the ether by rotary evaporation resulted in essentially pure product (2.83 g, 39 %) . ^XH NMR (C₆D₆, 200 MHz,) δ 6.76 (s, 2H, aryl-H) , 3-⁸¹ (s, 2H, CH_jCl) , 2.16 (s, 3H, p-Me) , 1.92 (s, 6H, o- e) , 1.40 (s, 3H, ΛfeC=N-) . ¹³C{^αH} NMR (CD₃CN, 75 MHz) δ 167.4 (CN) , 146.1, 133.2, 129.4, 126.1, 50.1 (CH₂) , 20.8 (Me) , 17.7 ip-Me) , 17.6 (o-Me) . Anal. Calcd. for C₁₅H₂₂C1N: C, 71.55; H, 8.81; Cl, 14.08; N, 5.56. Found: C, 71.91; H, 8.83; H, 5.32.

Example 3

[3 -Methyl- 1- {2- (2, 6-diisopropylphenylimino) propyl} imidazoliu ] chloride (3) .

1-methylimidazole (2.0 g, 24.4 mmol) and α-chloroimine 1 (3.0 g, 11.9 mmol) were heated at reflux in THF (100 mL) for 5 h. The mixture was concentrated to 20 mL by rotary -evaporation and cooled in a refrigerator overnight. The precipitated product was filtered and washed with ether. The product (2.5 g, 63 %) was recrystallized from dichloromethane/ether. ^XH NMR (CD₂C1₂, 200 MHz) δ 10.71 (br s, IH, NCHN) ) , 7.41 (t, J = 1.7 Hz, IH, HCCH) , 7.30 (t, J = 1.7 Hz, IH, HCCH) , 7.07 (m, 3H, aryl H) , 5.63 (s, 2H, CH₂) , 4.02 (s, 3H, NMe) , 2.46 (septet, J = 6.7 Hz, 2H, CaVIe₂) , 1.83 (s, 3H, MeC=N-) , 1.10 (d, J = 6.9 Hz, 6H, CHMe₂) , 1.00 (d, J - 6.9 Hz, 6H, CHMe₂) . ¹³C{^lΗ.} NMR (CDCI₃, 50 MHz, tentative assignments) δl63.4 (C=N) , 144.1 (aryl C_x ) , 139.1 (NCN) , 135.6 (NCCN) , 124.1 (NCCN) , 123.6 (aryl C ₄) , 123.0 (aryl C_3ιS) , 122.3 (aryl C_2ιS) , 55.2 (CH₂) , 36.6 (NMe) , 28.1 (MeC=N) , 23.0, 22.6 (CHMe₂ ) , 18.9 (CHMe₂) . IR (ATR, solid) v_c=N 1682 cm^"1. Anal. Calcd. for C₁₉H₂₈C1N₃ : C, 68.35; H, 8.45; Cl, 10.62; N, 12.58. Found: C, 72.18; H, 9.90; H, 9.84; Cl , 8.25.

Example 4

[1,3 -bis{2- (2,4, 6-trime hylphenylimino)propyl} imidazolium] chloride (4) .

A round-bottom flask was charged with imidazole (0.79 g, 0.012 mol), THF (10 mL) , and triethylamine (1.5 mL, 0.011 mol) . The mixture was stirred for 10 min before 1- chloro-2- (2 , 4 , 6-trimetylphenylimino) propane (4.9 g, 0.023 mol) was added. After 48 h of stirring at 55 °C, the solution was cooled to room temperature and the volatiles were removed under vacuum. To remove triethylammonium chloride from the product imidazolium salt, a saturated solution of K₂C0₃ was added. The imidazolium salt was extracted with dichloromethane and dried over K₂C0₃ before the solvent was removed by rotary evaporation. Yield, 250 mg (5 %) . ^XH NMR (CD₂C1₂, 200 MHz) δ 10.91 (s, IH, NCHN) , 7.40 (s, 2H, CHCH) , 6.78 (s, 4H, aryl H) , 5.45 (s, 4H, CH₂) , 2.21 (s, 6H, aryl p-Me) , 1.84 (s, 12H, aryl o-Me) , 1.78 (s, 6H, MeC=N-). "C^H}

NMR (CD₂C1₂, 75 MHz) δ 163.9 (C=N-), 144.5, 140.3, 133.0, 128.8, 125.6, 123.2, 55.6 (CH₂), 20.7 (aryl p-CH₃) , 18.4 (MeC=N-), 17.9 (aryl o-CH₃) .

cr

Example 5

3 -methyl-1-picolylimidazolium chloride (5) -¹ 1-Chloromethylpyridinium hydrochloride (1.0 g, 6.10 mmol) was suspended in THF (30 mL) . Triethylamine (0.65g, 6.40 mmol) was added and the contents were heated at reflux for 1 h. The mixture was cooled and filtered. The filtrate was concentrated to 10 mL. N- methylimidazole (0.5 g, 6.1 mmol) was added to the freshly prepared solution of 1-chloromethylpyridine and the contents were heated at reflux for 6 h. The solvent was removed in vacuo and the solid product was washed 3 times with ether. The product was dried under vacuum (6.9 g, 71%). ^XH ΝMR (CDCl₃, 200 MHz) δ 10.77 (s, IH, ΝCHΝ ), 8.47 (d, J = 4 Hz , IH, pyr 6-H) , 7.69 (m, 2H, pyr 3-H, 5-H) , 7.57 (s, IH, HCCH), 7.38 (s, IH, HCCH) , 7.26 (m, pyr 4-H) , 5.72 (s, 2H, CH₂) , 4.02 (s, 3H, NMe) .

"C H} ΝMR (CDC1₃, 50 MHz, tentative assignments) δ 152.0 (pyr C₂ ), 149.1 (pyr C_β) , 137.0, 136.8 (pyr C₄ and

ΝCΝ) , 123.2, 123.0, 122.8, 122.1 (pyr C₃, C₅, and ΝCCΝ ), 53.1 (CH₂), 35.9 (ΝMe) . Anal. Calcd. for C₁₀H₁₂ClΝ₃ : C, 57.28; H, 5.77; Cl , 16.91; N, 20.04. Found: C, 56.51; H, 5.73; N, 19.45.

McGuinness, D. S . ; Cavell, K. J. Organometallics 2000, 19, 741.

Ag Salt of 5-Carbene. Anal. Calcd. for C₂₀H₂₂Ag₂Cl₂N₆ C, 37.94; H, 3.50; Ag, 34.08; Cl , 11.20; N, 13.27. Found: C, 37.85; H, 3.46; N, 12.58.

Example 6

[Ag{3 -methyl-1- [2- (2, 6-diisopropylphenylimino)propyl] imidazolin-2-ylidene}₂] [AgCl₂] (6) .

A mixture of 3 (0.95 g, 2.8 mmol) and Ag₂0 ( 0.35 g, 1.51 mmol) in THF (30 mL) was stirred for 4 h. The solution was filtered through celite and the solvent was removed under vacuum. The mixture was washed with pentane . The product was recrystallized from dichloromethane/ether and dried under vacuum to give a light yellow powder (1.05 g, 83 %) . ^XH NMR (CDC1₃, 200 MHz) δ 7.03, 6.96 (m, 5H, aryl -H and NCHCHN) , 5.02 (s, 2H, CH₂) , 3.73 (3H, NMe), 2.49 (septet, J = 6 Hz , 2H, CHMe₂) , 1.63 (s, 3H, MeC=N) , 1.03, 1.00 (dd, J = 6.8 Hz, 12H, CHMe₂) . ¹³C{^XH} NMR (CDC1₃, 50.33 MHz) δl81.2 ( NOT), 164.6 (C=N), 144.5, aryl 1 - C) , 135.3, 123.5, 122.6, 122.2, 121.9 (NCCN, aryl C's), 58.1 (CH₂), 38.5 (NMe), 27.8 (CHMe₂), 22.8, 22.4 (CHMe₂) , 18.3 (-N=CCH₃). IR (CH₂C1₂) v_c=N 1682, 1663 cm^"1. Anal. Calcd for C38H54Ag2Cl2N6 (881.5290): C 51.78; H, 6.17; Cl 8.04; N 9.53. Found C 51.40; H 6.22; Cl 6.95; N 9.13; MS (ES) m/z 701 (M⁺-AgCl₂) .

Example 7

[Ag{l,3-bis [2- (2,4, 6- trimethylphenylimino)propyl] imidazolin-2-ylidene}₂] [AgCl₂] (7) .

To a solution of 2 (158 mg, 0.40 mmol) dichloromethane (2 mL) was added Ag₂0 (46 mg, 0.2 mmol) and the mixture was stirred for 1 h. The reaction mixture was filtered through celite, the volatiles were removed by vacuum transfer, and the residue was washed with ether. Yield 158 mg (70 %) . E NMR (CD₂C1₂, 200 MHz) δ 7.19 (s, 2H, NCHCHN), 6.80 (s, 4H, aryl 3 , 5-H) , 5.09 (s, 4H, CH,) , 2.22 (s, 6H, NMe), 1.89 (s, 12H, o-Me) , 1.68 (s, 6H, p- Me) . "C^H} NMR (CD₂Cl₂, 50 MHz) δ 165.5 (N=C) , 145.1, 132.8, 128.9, 125.5 (aryl C_{3 S}) , 122.8 (NCCN), 59.01 (CH₂) , 20.71 (N=CMe) , 18.1 (aryl o-Me) , 18.0 (aryl p-Me)

Example 8 PdCl₂[3-methyl-l-{2- (2,6- diisopropylphenylimino)propyl}imidazolin-2-ylidene] (8) .

A 5 mL CH₂C1₂ solution of 92 mg (0.32 mmol) (C0D)PdCl₂ was cooled down to -20 °C before carefully adding a 1 mL CH₂C1₂ solution of 141 mg (0.16 mmol) of [Ag{3 -methyl-1- [2- (2 , 6-diisopropylphenylimino) propyl] imidazolin-2- ylidene}₂] [AgCl₂] . After 1 hour of stirring he mixture was heated carefully up to room temperature before vaporization of the solvent. CF₃CH₂OH was used to extract the product out of the mixture. Crystallized upon cooling of the solution for 2-3 days. Air and moisture stable. (Anal. Calcd. for C19H27Cl2N3Pd (474.7690): C, 48.07; H, 5.73; Cl, 14.93; N, 8.85; Pd, 22.42.) Anal. Calcd. for C20H29Cl4N3Pd (559.7013): C, 42.92; H, 5.22; Cl, 25.34; N, 7.51; Pd, 19.01. Found: C, 44.07; H, 5.31; Cl, 22.8; N, 7.64; Pd, 20.0. ^XH NMR (DMSO, 200 MHz, 25°C) δ7.46 (m, 2H, HC=CH) , 7.06 (m, 3H, aryl-H), 5.04 (m, 2H, CH₂) , 3.96 (m, 3H, N-CH₃) , 2.76 (sep., J^" = 6.6 Hz, 2H, CH) , 1.40 and 1.06 and 0.85 (multiplets, 12H, C(CH₃)₂). "C H} NMR (dmso, 50 MHz, 25°C) δ 175.2 (NCN) , 167.5

(N=C) , 146.6 (aromatic C-N) , 136.7 (aromatic o-C) , 124.3 (p-CH) , 123.5 ( -CH) , 123.1 and 122.1 (HC=CH) , 58.66 (CH₂), 38.18 (N-CH₃), 28.78 (CH), 23.70 (doublet) and 23.20 (doublet) (C(CH₃)₂), 19.01 (CH₃), -9.03 (Pd-CH₃).

Example 9 PdClMe[3-methyl-l-{2- (2,6- diisopropylphenylimino)propyl}imidazolin-2-ylidene] (9) .

A 5 mL CH₂C1₂ solution of 99 mg (0.37 mmol) (COD)PdClMe was cooled down to -20 °C before carefully adding a 1 L CH₂C1₂ solution of 165 mg (0.19 mmol) of [Ag{ 3 -methyl-1- [2- (2, 6-diisopropylphenylimino) propyl] imidazolin-2- ylidene}₂] [AgCl₂] . After 1 hour of stirring he mixture was heated carefully up to room temperature before vaporization of the solvent. The decided product was dissolved in toluene before filtration through celite to remove AgCl . Toluene was removed under vacuum and the product crystallized from cold diethyl ether. Yield: 103 mg (60%). Anal. Calcd. for C20H30ClN3Pd (454.35): C, 52.87; H, 6.66; Cl, 7.80; N, 9.25; Pd, 23.42. Fond: C, 52.85; H, 6.55; Cl , 8.12; N, 9.42; Pd, 23.48. . ^XH NMR

(d₈-THF, 300 MHz, 25°C) δ7.15(m, 2H, HC=CH) , 7.01 (m, 3H, aryl-H), 5.53 (broad, 2H, CH₂) , 4.05 (s, 3H, N-CH₃), 2.79

(Sep., J = 6 . 6 Hz, 2H, CH) , 1.82 (s, 3H, CH₃) , 1.12 (m, 12H, C(CH₃)₂, 0.31 (s, 3H, PdCH₃) . "C^H} NMR (d_s-THF, 75

MHz, 25°C) δ 175.2 (NCN) , 167.5 (N=C) , 146.6 (ipso. diisopropylphenyl) , 136.7 (o-diisopropylphenyl) , 124.3 (p- diisopropylphenyl), 123.5 (m- diisopropylphenyl), 123.1 and 122.1 (HC=CH) , 58.66 (CH₂), 38.18 (N-CH₃), 28.78 (CH) , 23.70 (doublet) and 23.20 (doublet)

(C(CH₃)₂), 19.01 (CH₃) , -9.03 (Pd-CH₃). IR (in CH₂C1₂)

1678.46, 1660.95, 1645.94, 1460.82.

Example 10

1- (2,4, 6-Trimethylphenyl) imidazole (10) .

Paraformaldehyde (2.30 g, 74.0 mmol ) was suspended in n-propanol (30 mL) and cooled to 0°C. The mixture was charged with 12M aqueous NH₃ (6.20 mL, 74.0 mmol) while stirring. After 30 min, 8.8 M glyoxal solution (10.4 mL, 74.0 mmol) and 2 , 4 , 6-trimethylphenylaniline (10.0 g, 74.0 mmol) were added to the flask and the mixture was allowed to warm to room temperature. After 1 h of stirring, the mixture was heated at reflux for 10 h. The solvent was evaporated under vacuum and the mixture was purified by repeated vacuum distillation (0.05 mbar, temperature ca. 80 °C) . Yield, 2.2 g (16%). ^XH NMR (CD₂C1₂, 300 MHz) δ 7.40 (s, IH, NCHN ), 7.17 (s, IH, NCHCHN), 6.98 (s, 2H, aryl H_{3ι S}) , 6.91 (s, IH, NCHCHN), 2.32 (s, 3H, p-Me) , 1.97 (s, 6H, o-Me) . "C^H} NMR (CD₂C1₂, 75 MHz, tentative assignments) δ 139.2 (aryl C- N) , 137.8 (NCN) , 135.8, 135.6 (aryl C_2/ff and C₄) , 129.6, 129.2 (NCCN, aryl C_{3ι 5}) , 120.5 (NCCN), 21.1 (aryl p-Me) ,

17.5 (aryl m-Me) . MS (El) m/z 186 (100, M⁺) . Anal. Calcd. for C₁₂H₁₄N₂: C, 77.38; H, 7.58; N, 15.04. Found: C, 76.84; H, 7.53; N, 15.63.

Example 11

1- (2, 6-Diisopropylphenyl) imidazole (11) .

A round-bottom flask was charged with π-propanol (30 L) and paraformaldehyde (1.69 g, 56.4 mmol) and cooled to 0°C. Aqueous NH₃ (4.7 mL of 12 M, 56 mmol) was slowly added to the contents while stirring. After 1 h, glyoxal (6.4 mL of 8.8 M solution, 56.4 mmol) and 2,6- diisopropylaniline (10.00 g, 56.4 mmol) were added to the flask and the mixture was allowed to warm to room temperature. The mixture was allowed to stir at ambient temperature for 2 h. The temperature of the mixture was raised to 80 °C and stirring was continued for 12 h. The solvent was removed under vacuum and the product was purified by repeated vacuum distillation/sublimation

(0.06 mbar, temperature ca. 85°C) . Yield, 2.1 g (16%). ¹H ₍NMR (CD₂C1₂, 300 MHz) δ 7.43 (s, 2H, NCHN and NCHCHN), 7.26 (s, 2H, aryl H_3/S) , 7.17 (s, IH, aryl H_t) , 6.95 (s, IH, NCHCHN), 2.38 (septet, J = 6.8 Hz, 2H, CHMe₂) , 1.12 (d, J = 6.8 Hz, 12H, CHMe₂) . ¹³C H} NMR (CD₂Cl₂, 75 MHz) δ

147.0, 138.8, 133.4, 130.1, 129.4, 124.1, 122.0, 122.0 (aryl and imidazole ring C's) , 28.5 (aryl C₄ ) , 24.5 (aryl C_3tS) . MS (El) m/z 228 (M\ 100%) . Anal. Calcd. for C_1SH₂₀N₂: C, 78.90; H, 8.83; N, 12.27. Found: C, 79.19; H,

8.99; N, 11.64.

Example 12

[3- (2, 6-diisopropylphenyl) -l-{2- (2,6- diisopropylphenylimino)propyl}-imidazolium] chloride (12) .

1- (2 , 6-diisopropylphenyl) imidazole (146 mg, 0.64 mmol) and l-Chloro-2- (2 , 6-diisopropylphenylimino) propane

(164 mg, 0.65 mmol) were stirred in 3 mL MeCN at 40°C fore 4 days . MeCN was removed under vacuum and the residue washed with pentane Yield: 200 mg (65 %) . ^XH NMR (CDC1₃, 200 MHz, 25°C) δ 10.16 (s, IH, NCHN), 7.92 (s, IH, HCCH near imine), 7.50 (m, IH, p-Ar-H imidazol- aromat) , 7.28 (m, 2H, m-Ar-H imidazol-aromat) , 7.11 (s, IH, HCCH), 7.06 (m, 3H, m- and p-Ar-H imino-aromat) , 6.11 (s, 2H, CH₂) , 2.53 (septet, J^" = 6.8 Hz, 2H, CHMe₂ imin-aromat) , 2.35 (septet, J = 6.8 Hz , 2H, CHMe₂ imidazol-aromat), 1.89 (s, 3H, p-CH₃) , 1.13 and 1.07 (d, J = 6.8 Hz, 6H, CHMe₂ imidazol-aromat), 1.11 and 0.99 (d, J = 6.8 Hz, 6H, CHMe₂ imin-aromat). "C^H} NMR (CDC1₃, 50 MHz, 25°C) δ 163.9 (C=N), 145.54 (p-Ar-C imidazol- aromat) 144.23 (ipso-Ar-C imin-aromat) 139.8 (NCN), 135.9 (o-Ar-C imin-aromat), 131.9 (o-Ar-C imidazol-aromat), 130.2 (ipso-Ar-C imidazol-aromat), 124.6 (m-Ar-C imidazol-aromat) 124.3 (NCCN) 124.1 (NCCN near imin)123.0 (m- and p-Ar-C imino-aromat) , 55.49 (CH₂),

28.58 (CHMe₂ imidazol-aromat), 28.13 (CHMe₂ imin-aromat),

24.34 and 24.09 (C(CH₃)₂ imidazol-aromat) 23.15 and 22.71

(C(CH₃)₂ imin-aromat), 19.08 (CCH₃) . Anal Calcd for

C30H42C1N3 (480.1364); C 75.05; H 8.82; Cl 7.38; N 8.75. Found C 71.54; H 8.42; Cl 7.59; N 8.49. MS (ES) : m/z 444 (M⁺-C1) .

Example 13

[3- (2,4, 6-trimetylphenyl) -l-{2- (2,6- diisopropylphenylimino)propyl} -imidazolium] chloride (13) .

1- (2 , 4 , 6-trimethylphenyl) imidazole (288 mg, 1.55 mmol) and l-Chloro-2- (2 , 6-diisopropylphenylimino) propane (391 mg, 1.55 mmol) were stirred in 3 mL MeCN at 40°C for 4 days. MeCN was removed under vacuum and the residue washed with pentane Yield: 500 mg (74 %) . ^Η NMR (CDC1₃, 200 MHz, 25°C) δ 10.25 (s, IH, NCHN), 7.75 (s, IH, HCCH), 7.09 (s, IH, ^'HCCH) , 7.02 (m, 3H, m- and p- diisopropylphenyl-H) , 6.95 (s, 2H, m-trimetylphenyl-H) , 6.02 (s, 2H, CH₂) , 2.51 (septet, J = 6.8 Hz, 2H, CHMe₂) , 2.29 (s, 3H, p-CH₃) , 2.01 (s, 6H, o-CH₃) , 1.11 and 0.96 (d, J = 6.8 Hz, 6H, CHMe₂) AC^H} NMR (CDC1₃, 50 MHz, 25°C) δ 163.4 (C=N), 143.7 (ipso-diisopropylphenyl- ) , 140.7 (p-trimethylphenyl-C) , 138.9 (NCHN, 135.4 (o- diisopropylphenyl- C) , 133.8 (o-trimethylphenyl-C), 130.1 (ipso-trimethylphenyl-C) , 129.2 (m-trimethylphenyl-C) , 123.9 (NCCN), 123.5 (p-diisopropylphenyl-C) 122.4 (m- diisopropylphenyl-C) , 121.3 (NCCN), 54.88 (CH₂), 27.54 (CHMe₂), 22.68 and 22.03 (C(CH₃)₂), 20.50 (p-CH₃), 18.36 (CCH₃) , 16.84 (o-CH₃) . Anal Calcd for C27H36C1N3 (438.0558); C 74.03; H 8.28; Cl 8.09; N 9.59. Found C 69.92; H 8.39; Cl 7.52; N 9.06. MS (ES) : m/z 402 (M⁺-C1).

Example 14

[Ag{3- (2,4, 6-trimethylphenyl) -1- [2- (2,6- diisopropylphenylimino)propyl] -imidazolin-2- ylidene}₂] [AgCl₂] (14) .

[3- (2,4, 6-trimethylphenyl) -l-{2-(2,6- diisopropylphenylimino) propyl} -imidazolium] chloride (200 mg, 0.457 mmol), Ag₂0 (63 mg, 0.27 mmol), 10 mL CH₂C1₂. Yield: 130 mg (25%) . ^XH NMR (CDCl₃, 200 MHz, 25°C) 7.25 (s, 2H, HC=CH) , 7.05 ( , 6H m- and p- diisopropylphenyl-H) , 6.93 (s, 2H, HC=CH) , 6.91 (s, 4H, m-trimethylphenyl-H) , 5.15 (s, 4H, CH₂) , 2.56 (septet, J = 6.8 Hz, 4H, CHMe₂) , 2.29 (s, 6H, p-CH₃) , 1.94 (s, 12H, o-CH₃) 1.74 (s, 6H, MeC=N) , 1.11 and 1.04 (d, J^"=6.8 Hz, 24H, CH(CH₃)₂) . ¹³C{^XH} NMR (CDCl₃) , 50 MHz) 164.1 (C=N) , 144.7 (ipso-C, diisopropylphenyl), 139.5 (p-C, trimethylphenyl), 135.6 (o-C, diisopropylphenyl), 135.1 (ipso-C, trimethylphenyl), 134.6 (o-C, trimethylphenyl), 129.3 (m-C, trimethylphenyl), 123.8 (p-C, diisopropylphenyl), 122.9 (m-C, diisopropylphenyl), 122.6 and 122.3 (NC=CN) , 58.38 (CH₂), 28.15 (C(CH₃)₂), 23.18 and 22.56 (C(CH₃)₂), 20.95 (p-CH₃), 18.48 (CCH₃) ,

17.49 (o-CH₃) . IR (CH₂Cl₂) V_C=N 1684, 1666 cm^"1.

Example 15 [Ni{3 -Methyl-1- (2- (2, 6-diisopropylphenylimino) - propyl) imidazolin-2~ylidene}Br₂] (15) .

To a suspension of NiBr₂ (82 mg, 0.38 mmol) in acetonitrile (5 mL) was added [Ag{l, 3-bis [2- (2 , 6- diisopropylphenyl-imino) -propyl] imidazolin-2- ylidene}₂ [AgCl₂] (6) (165 mg, 0.187 mmol) dissolved in acetonitrile (5 mL) . After stirring for 1 h .at ambient temperature, the color had changed from yellow to green. The solution was filtered and concentrated by vacuum transfer. Yield: 50 mg. ^XH NMR (THF-d_B, 200 MHz) δ 10.59 (br s, IH) , 7.9 (br s, IH) , 7.7 (br s, IH) , 7.1 (br m,

2H) , 6.3 (br s, 2H, CH₂) , 4.4 (br s, 3H, NMe), 2.7 (br s, 2H, CHMe₂) , 1.95 (br s, 3H, NCMe) , 1.1 (br d, 12 H, CHMe,) .

Example 16

[Ni{3 -Methyl-1- (2- (2 , 6-diisopropylphenylimino) propyl) imidazolin-2-ylidene}Cl₂] (16) .

To a solution of NiCl₂(PMe₃)₂ (104 mg, 0.48 mmol) in THF (5 mL) was added a THF solution (5 mL) of [Ag{l, 3-bis [2- (2, 6-diisopropylphenylimino) -propyl] imidazolin-2- ylidene}₂ [AgCl₂] (6) (210 mg, 0.24 mmol). The color changed from a clear red to a clear yellow solution after 20 s. The solution was filtered and concentrated by vacuum transfer.¹H NMR (CD₂C1₂, 200 MHz) δ 7.48 (s) , 7.1 (m) , 5.8 (s) , 4.1 (s) , 2.6 (m) , 2.0 (s) , 1.3 (m) . Anal. Calcd. for C₁₉H₂₇Cl₂N₃Ni : C, 53.44; H, 6.37; Cl , 16.60; N, 9.84; Ni , 13.74. Found: C, 57.78; H, 7.11; N, 9.23.

Example 17

FeCl₂ [3-Methyl-l- (2- (2, 6-diisopropylphenylphenylimino) propyl) imidazolin-2-ylidene] (17) .

A solution of the silver carbene 6 (122 mg, 0.14 mmol) in CH₂C1₂ (2 mL) was added to a suspension of FeCl₂ (35 mg, 0.28 mmol) in CH₂C1₂ (5 mL) . After 30 min of stirring, the color of the mixture had turned from brown to yellow, and a precipitate of AgCl was observed. The precipitate was removed by filtration and the solvent was removed under vacuum. ^XH NMR (THF-d_8; 200 MHz) δ 42.84, 33.8, 8.2, 1.4, -0.2, -2.1, -6.0. MS (El) m/z 423 (100, M⁺) , 388 (35, M⁺-Cl) , 296 (50, free iminocarbene ligand*) .

R =2,6-diisopropylphenyl

Example 18 CoCl₂ [3-Methyl-l- (2- (2, 6-diisopropylphenylphenyl- i ino) propyl) imidazolin-2 -ylidene] (18) .

A solution of the silver carbene 6 (44 mg, 0.05 mmol) in THF (2 mL) was added to a suspension of CoCl₂ (13 mg, 0.1 mmol) in THF (5 mL) . After 30 min of stirring, the pale blue suspension had changed to a clear blue solution in which was seen a precipitate of AgCl . The precipitate was removed by filtration, and the product was precipitated by addition of pentane to the filtrate . ¹H NMR (THF-d_8; 200 MHz) δ 48.4, 44.8, 18.4, 10.1, 7.0, 2.2, 1.0, -0.2. IR V_C=N 1640cm^"1. MS (El) m/z 426 (11, M⁺) , 391 (25, M⁺-C1,), 296 (100, free iminocarbene ligand⁺) .

R¹ =2,6-diisopropylphenyl

Example 19

NiCl₂ [3-Methyl-l- (2- (2, 6-diisopropylphenylphenyl- ^■ imino) propyl) imidazolin-2 -ylidene] ₂ (19) .

The silver carbene 6 (44 mg, 0.05 mmol) was added to a solution of Ni(cod)₂ (27 mg, 0.1 mmol) in THF (5 mL) . After lh of stirring at ambient temperature, a black precipitate had formed and a thin film of Ag was observed on the glass wall . The mixture was filtered trough celite, and the product was precipitated as red crystals by addition of pentane. ¹H NMR (THF-d₈, 200 MHz) δ 7.00 (m, 5H, aryl-H and NCHCHN), 6.00 (br s, 2H, NCH₂) , 4.49 (br s, 3H, NMe), 2.89 (septet, J = 6 Hz, 2H, CHMe₂) , 1.97 (s, 3H, NCMe) , 1.12 (d, J = 6 Hz, 6H, CHMe₂) , 1.09 (d, J = 6 Hz, 6 H, CHMe₂) . MS (El) m/z 722 (1, M⁺) , 687 (2, M⁺-C1) , 296 (100, free iminocarbene ligand*).

Example 20 PdCl₂ [3- (2,4, 6-trimethylphenyl) -l-{2- (2,6- diisopropylphenylimino) propyl}-imidazolin-2 -ylidene]

(20) .

A 5 L CH₂C1₂ solution of 53 mg (0.18 mmol) (COD)PdCl₂ was carefully added a 1 mL CH₂C1₂ solution of 100 mg (0.089 mmol) of [Ag{3- (2 , 4 , 6-trimethylphenyl) -1- [2- (2 , 6- diisopropylphenylimino) propyl] imidazolin-2- ylidene}₂] [AgCl₂] . After 1 hour of stirring the mixture was filtered through celite. CH₂C1₂ was removed under vacuum and the residue washed with MeCN to remove excess of (C0D)PdCl₂. Yield: 47 mg (43.7 %) . ^λE NMR (CD₂C1₂, 200 MHz, 25°C) δ 7.23 and 7.21 (d, IH, «J=1.8 Hz, HC=CH near imin) , 7.08 (m, 3H, m- and p-aryl-H) , 6.97 and 6.91 (s, 2H, m-aryl-H) , 6.81 and 6.78 (d, IH, =l .8 Hz, HC=CH near 2 , 4 , 6-trimethylphenyl) , 5.65 and 5.23 (s, 2H, CH₂) ,

2.66 (Sep., 2H, !J=6.8Hz, CHMe₂) , 2.48 and 2.29 (s, 3H, p-

CH₃) , 2.21 and 1.90 (s, 6H, m-CH₃) , 1.95 and 1.64 (s, 3H,

CH₃) , 1.12 and 1.09 (d, 12H, ι7=6.8, CH(CH₃)₂). "C^H} NMR

5 ^• (CD₂C1₂, 50 MHz, 25°C) δ 171.6 (NCN), 167.1 (C=N), 145.7

(ipso-diisopropylphenyl) , 138.9 (ipso-trimethylphenyl) , 137.0 (p-trimethylphenyl) , 136.5 (o-trimethylphenyl) , 136.3 (o-diisopropylphenyl) , 129.0 (m-trimethylphenyl) , 124.0 (p-diisopropylphenyl) , 123.2 (m- 10 diisopropylphenyl), 123.1 (HC=CH, near phenyl), 122.2

(HC=CH, near imin) , 57.62 (CH₂), 28.18 (CHMe₂) , 23.58 and

23.14 (CH(CH₃)₂), 21.21 (p-CH₃), 19.32 and 18.60 (o-CH₃),

18.98 (CH₃) .

T_ 5 Mes = 2,4,6-trimethylphenyl

Example 21

PdCl₂ [3 - (2 , 6 -diisopropylphenyl) -l - {2 - (2 , 6 - diisopropylphenylimino) propyl } -imidazolin- 2 -ylidene]

20 (21) .

A 5 mL CH₂C1₂ solution of 36 mg (0.12 mmol) (COD)PdCl₂ was carefully added a 1 mL CH₂C1₂ solution of 73 mg (0.062 mmol) of [Ag{3- (2 , 6-diisopropylphenyl) -1- [2- (2 , 6- diisopropylphenylimino) propyl] imidazolin-2- 25 ylidene}₂] [AgCl₂] . After 1 hour of stirring the mixture was filtered through celite. CH₂C1₂ was removed under vacuum and the residue washed with MeCN to remove excess of (COD)PdCl₂. Yield: 13 mg (16.6%) . ^XU NMR (CD₂C1₂, 200 MHz, 25°C) δ 7.40, 7.28 and 7.02 (m, 8H, HC=CH, aryl-H) , 5.85 and 5.27 (s, 2H, CH,) , 2.92 (sep., 2H, J=6.8 Hz, CHMe₂) , 2.60 (sep., 2H, J=6.8 Hz, CHMe₂) , 1.45 (s, 3H, CH₃) , 1.31 and 0.96 (d, 12H, ,7=6.8, CH(CH₃)₂) , 1.11 and 1.08 (d, 12H, J=6.8, CH(CH₃)₂) . "C HJ NMR (CD₂Cl₂, 50

MHz, 25°C) δ 147.8 (ipso-imidazolaryl) , 145.8 (ipso- iminaryl) , 136.5, 130.0, 125.0, 123.8, 123.2, 121.2, 57.60 (CH₂) , 28.66, 28.21, 26.59, 23.48, 23.00, 22.93,

19.62.

Ar = 2,6-diisopropyIphenyl

Example 22

[Ag{3- (2, 6 -diisopropylphenyl) -1- [2- (2, 6- diisopropylphenylimino) ropyl] -imidazolin-2- ylidene}₂] [AgCl₂] (22) .

[3- (2 , 6 -diisopropylphenyl) -l-{2-(2,6- diisopropylphenylimino) propyl] imidazolium chloride

(108 mg, 0.225 mmol) , Ag₂0 (36 mg, 0.155 mmol) , 10 mL CH₂C1₂. Yield: 78 mg (30%) . "Η NMR (CDCl₃, 200 MHz, 25°C) δ 7.45 (m, 2H, p-imidazolaryl) , 7.28 (s, 2H, HC=CH near imin) , 7.24 (m, 4H, m-imidazolaryl) 7.10 (m, 4H, m-and p-iminaryl) , 7.00 (s, 2H, HC=CH near aryl) , 5.17 (s, 4H,

CH₂) , 2.58 (septet, J = 6.8 Hz, 4H, CHMe₂) , 2.40 (septet, J = 6.8 Hz, 4H, CHMe₂) , 1.76 (s, 6H, MeC=N) , 1.17 and

1.06 (d, J=6.8 Hz, 12H, CH(CH₃)₂) 1.13 and 1.06 (d, =6.8

Hz, 12H, CH(CH₃)) . ¹³C{^XE} NMR (CDC1₃, 50 MHz, 25°C) δ 164.0 (N=C) , 145.7 (o-imidasolaryl) , 144.8 (ipso- iminaryl) , 135.7 (o- iminaryl) , 134.5 (ipso- imidasolaryl) , 130.6 (p-imidazolaryl), 124.2 (m- iminaryl) , 124.1 (HC=CH near aryl) 123.9 (p- iminaryl), 122.9 (m- imidazolaryl) , 121.76 (HC=CH, near imin) , 58.50 (CH₂), (N-CH₃), 28.30 (CHMe₂), 28.22 (CHMe₂), 24.41 and 24.34 (C(CH₃)₂), 23.20 and 22.59 (C(CH₃)₂), 18.58 (CCH₃) . IR (CH₂C1₂) V_C=N 1684, 1666 cm^"1. MS (El): m/z 993 (M⁺-AgCl₂) .

Example 23

[Cr{l-methyl-3 - (2 - (2 , 6 - diisopropylphenylimi.no) propyl) imidazolin-2 -ylidene}Cl₃]

(23 ) .

The silver carbene complex 6 (100 mg, 0.11 mmol) was added to a stirred solution of CrCl₃(THF)₃ (85 mg, 2.3 mmol) in dichloromethane. The solution turned green and white AgCl precipitated. The mixture was filtered and the filtrate was evaporated to dryness. The product was dissolved in THF and crystallized upon the addition of ether. ^XH NMR (CD₂C1₂) δ 7.5 (br) , 5.5 (br) , 2.2 (br) . Anal. Calcd. for C₁₉H₂₇Cl₃CrN₃ : C, 50.07; H, 5.97; Cl , 23.33; Cr, 11.41; N, 9.22. Found: C, 48.17; H, 6.35; N, 7.54; Cr, 11.59; Cl , 19.65.

R =2,6-diisoρropylphenyl

Example 24

CoCl₂ [3- (2, 6 -diisopropylphenyl) -1- (2- (2, 6-diisopropyl- phenylphenylimino) propyl) -imidazolin-2-ylidene] (24).

A solution of the silver carbene 6 (80 mg, 0.08 mmol) in

THF (2 mL) was added to a suspension of CoCl₂ (25 mg, 0.19 mmol) in THF (5 mL) . After 30 min of stirring, the pale blue suspension had changed to a clear blue solution in which was seen a precipitate of AgCl . The precipitate was removed by filtration, and the product was precipitated by addition of pentane to the filtrate. ^λΗ. NMR (THF-d_8; 200 MHz) δ 47.9, 33.8, 12.8, 8.2, 2.7,

1.4, -0.3, -3.0, -4.4, -20.0.

R =2,6-diisoρropylphenyl

Example 25

[Cr{l- (2,4, 6-trimethylphenyl) -3- (2- (2,6- diisopropylphenylimino) ropyl) imidazolin-2-ylidene}Cl₃] (25) .

The silver carbene complex 6 was added to a stirred solution of CrCl₃(THF)₃ in dichloromethane. The solution turned green and white AgCl precipitated. The mixture was filtered and the filtrate was evaporated to dryness. The product was dissolved in THF and crystallized upon the addition of ether. Anal. Calcd. for C₂₇H₃₅Cl₃CrN₃ : C, 57.92; H, 6.30; Cl , 18.99; Cr, 9.29; N, 7.50. Found: C, 49.18; H, 5.87; N, 5.75; Cl , 19.09; Cr, 9.63.

R =2,6-diisopropylphenyl R² =2,4,6-trimethylphenyl

Example 26 [Cr{l- (2, 6 -diisopropylphenyl) -3- (2- (2,6- diisopropylphenylimino)propyl) imidazolin-2-ylidene}Cl₃] (26) .

The silver carbene complex 6 was added to a stirred solution of CrCl₃(THF)₃ in dichloromethane. The solution turned green and white AgCl precipitated. The mixture was filtered and the filtrate was evaporated to dryness.

The product was dissolved in THF and crystallized upon the addition of ether.

R =2,6-diisopropylphenyl

Example 7

Polymerization Experiments Part I .

The reactors were charged with toluene, and MAO (2.7 mL, 12 mmol Al, PMAO from Akzo, 13% Al) . All complexes (0.03 mmol) were dissolved in toluene and added to the reactors. The polymerization lasted for 60 min with 1 bar ethene pressure and a reactor temperature of 30 °C.

Polymerization Experiments Part II. The reactors were charged with toluene, and MAO (Al/M=400, PMAO from Akzo, 13% Al) . All complexes were dissolved in toluene and added to the reactors. The polymerization lasted for 40 min with 1 bar ethene pressure and a reactor temperature of 30 °C.

* Calculated from mL ethene gas used.

** Isolated yield. Thermal analysis gave melting peak at

T= 127.6 °C, Area = 98.9mJ, delta H=109.8.

Polymerization Experiments Part III. The reactors were charged with toluene, and MAO (Al/M=400, PMAO from Akzo, 13% Al) . All complexes were dissolved in toluene and added to the reactors. The polymerization lasted for 40 min with 1 bar ethene pressure and a reactor temperature of 30 °C.

* ctivity was observed, but no polymer was separated. GC running to find oligomeres.

** Calculated from mL ethene gas used.

Example 28

[3 -phenyl-1-{2- (2, 6-diisopropylphenylimino) propyl} imidazolium] chloride (27) .

1-phenmylimidazole (485.4 mg, 3.37 mmol) and l-Chloro-2- (2 , 6-diisopropylphenylimino) ropane (847.8 mg, 3.36 mmol) were stirred in 3 mL THF at ambient temperature for 70 h. Diethyl ether was added to precipitate the product before filtration and washing with small portions of diethyl ether. Yield: 835 mg (62 %) . ^XH NMR (CDC1₃, 200 MHz) δ 11.13 (s, IH NCHN), 7.64 (m, 4H, NCHCHN and m-phenyl-H) , 7.51 (m, 3H, o- and p- phenyl-H) , 7.02 (m, 3H, m- and p-diisopropylphenyl-H) , 5.88 (s, 2H, CH,) , 2.51 (septet, J=6.7 Hz, 2H, CH(CH₃)₂), 1.86 (s, 3H, CH₃) , 1.11 and 0.95 (d, J=6.8 Hz, 12H, C(CH₃)₂) ."CjH} NMR (CDCI₃, 50 MHz) δ 163.6 (C=N), 144.1 (ipso-C, diisopropylphenyl) , 137.6 (NCHN) , 135.7 (o-C, diisopropylphenyl) , 134.4 (ipso-C, phenyl) , 130.6 (o-C, phenyl) , 103.3 (p-C, phenyl) , 124.6 and 119.4 (NC=CN) ,

124.1 (p-C, diisopropylphenyl) , 123.0 (m-C, diisopropylphenyl) , 121.8 (m-C, phenyl) , 55.45 (CH₂) ,

28.13 (CH(Me)₂) , 23.02 and 22.49 (C(CH₃)₂) , 18.98 (CCH₃) .

Anal Calcd for C24H30C1N3 (395.9751) ; C 72.80; H 7.64; Cl 8.95; N 10.61. Found C 68.20; H 7.79; Cl 8.43; N 9.57. MS(ES) : m/z 360 (M⁺-Cl) .

Example 29

[Ag (imino-imidazolin-2-yliden) ₂] [AgCl₂] .

(General procedure) . The imino-imidazolium chloride was dissolved in dichloromethane and added a slurry of Ag₂0 in CH₂C1₂. The mixture was stirred for 30 min. at ambient temperature before filtration through celite to remove the excess of Ag₂0. Dichloromethane was vaporized under vacuum and the product dried. Recrystallized from dichloromethane/pentane. Air stable yellowish powder.

Example 30

[Ag{3 -phenyl-1- [2- (2,6- diisopropylphenylimino) propyl] imidazolin-2- ylidene}₂] [AgCl₂] (28) .

[3 -phenyl-1- {2- (2 , 6-diisopropylphenylimino) propyl} - imidazolium] chloride (224 mg, 0.566 mmol), Ag₂0 (70 mg, 0.302 mmol), 10 mL CH₂C1₂. Yield: 196 mg (69%). ^XH NMR

(C₆D₆, 200 MHz, 25°C) δ 7.30 (m, 4H, aryl-H ), 7.03 (m, 12H aryl-H) 6.75 and 6.52 (d, J=l .7 Hz, 4H, HC=CH) , 4.92 (s, 4H, CH,) , 2.81 (septet, J^" = 6.8 Hz, 4H, CHMe₂) , 1.51 (s, 6H, MeC=N) , 1.24 and 1.13 (d, J= .8 Hz, 24H, CH(CH₃)₂). "CfH} NMR (C₆D₆, 50 MHz) δ 182.5 (NCN), 165.5 (C=N) , 145.8 (ipso-Ar-C diisopropylphenyl) , 140.3 (ipso- Ar-C phenyl), 136.0 (o- C) , 129.7 (phenyl-CH) 128.3 (phenyl- CH) , 124.1 (p-Ar-C diisopropylphenyl) , 124.0 (phenyl-CH), 123.4 (HC=CH) , 123.3 (m-Ar-C diisopropylphenyl) 120.8 (HC=CH) , 58.24 (CH₂), 28.58 (CHMe₂) , 23.54 and 22.98 (C(CH₃)₂), 18.63 (CCH₃) . IR

(CH₂C1₂) V_C=N 1684, 1666 cm^"1. MS (El): m/z 825 (M⁺-AgCl₂) .

Example 31

PdCl₂[3-phenyl-l-{2- (2,6- diisopropylphenylimino)propyl}imidazolin-2 -ylidene] (29) .

A 5 mL CH₂C1₂ solution of 51 mg (0.18 mmol) (C0D)PdCl₂ was carefully added a 1 mL CH₂C1₂ solution of 90 mg (0.089 mmol) of [Ag{3 -phenyl-1- [2 - (2 , 6- diisopropylphenylimino) propyl] imidazolin-2- ylidene}₂] [AgCl₂] . After 1 hour of stirring the mixture was filtered through celite. CH₂C1₂ was removed under vacuum and the residue washed with MeCN to remove excess of (COD)PdCl₂. The product is air and moisture stable for a shorter period of time. Yield: 22 mg (23 %) . ^XH-NMR (CH₂C1₂, 300 MHz, 25°C) δ 8.1 (d, 2H, J=7.4Hz, o-phenyl) , 7.61 (m, 2H, m-phenyl) , 7.50 (m, IH, p-phenyl) , 7.24 (d, IH, =1.9Hz, HC=CH near phenyl) , 7.18 (d, IH, J=1.9Hz, HC=CH near imin) , 7.10 (m, 3H, m- and p- diisopropylphenyl) , 5.40 (s, 2H, CH₂) , 2.74 (sep., 2H, -=6.8Hz, CHMe₂) , 1.66 (s, 3H, CH₃) , 1.17 and 1.14 (d, 12H, J=6.8Hz, CH(CH₃)₂) . "C^H} NMR (CD₂C1₂, 75 MHz, 25°C) δ 171.9 (NCN), 166.7 ( =N) , 145.6 (ipso- diisopropylphenyl) , 140.8 (ipso-phenyl) , 136.3 (o- diisopropylphenyl) , 129.4 (m-phenyl), 128.6 (p-phenyl), 126.4 (o-phenyl), 124.1 (p-diisopropylphenyl), 123.3 (m- diisopropylphenyl) , 122.8 (HC=CH, near phenyl), 121.8

(HC=CH, near imin), 58.45 (CH₂) , 28.36 (CHMe₂) , 23.44 and

23.05 (CH(CH₃)₂) , 19.08 (CH₃) .

Ar=2, 6-diisopropylpheny Example 32

Polymerization Experiments.

The reactors were charged with toluene and 0.02 mmol catalyst, and added MAO (Al/Pd=200, PMAO from Akzo, 13% Al) . No consumption of ethylene was observed. Experiment conditions: 1 bar ethylene pressure and a reactor temperature of 30 °C.

Claims

1. The use of a complex of a group 3 to 10 transition metal or a lanthanide (M) and a ligand of formula I

R*-L[A-L]_nA-L[A-L]_pA-L-R* (I)

A

L

I

(wherein each group A, which may be the same or different, is an M-coordinating carbon or heteroatom or η^q group, at least one group A being an M-coordinating carbene carbon, silicon, germanium or phosphorus (i.e. C:, Si:, Ge : or P : ) which is a ring member of a 4- or 5- ring atom heterocycle; each L, which may be the same or different, is a bond or bridging group providing a 1 to 5 atom chain between the groups it connects;

R is a hydrogen atom or a C_x_₂₀ hydrocarbyl group optionally attached by a silicon atom or a Si-O- group; each R* , which may be the same or different, is a group R or together both R* are a bond whereby to form an 8 to 22 ring atom macrocycle; n is 0 or 1; m is 0 or 1; p is 0, 1 or 2; and q is an integer having a value of 2 to 6; with the provisos that where n, m and p are o and each R* is a group R then one A group is a carbene silicon or germanium atom and the other A group is a carbene carbon, silicon, germanium or phosphorus atom, a nitrogen atom or a η^q group or one A group is a carbene carbon atom and the other A group is a carbene carbon, silicon, germanium or phosphorus atom, a ring nitrogen in a 5 or 6 membered heterocycle, an open chain η^q group, or less preferably an N^Θ, and that where the sum of n, m and p is zero or 1, each R* is a group R, one A is a carbene carbon atom and M is a group 6 transition metal then another A group is a carbene silicon, germanium or phosphorus atom, a ring nitrogen in a 5 or 6-membered heterocycle, an open chain η^g group or, less preferably, an N^θ) as a catalyst, procatalyst, or catalyst precursor, especially as a catalyst or procatalyst for olefin polymerization.

2. Use as claimed in claim 1 wherein at least one group A is of formula (II)

where Y is C:, Si: or Ge : ; each X is N or P; Z is N or CR³; each R³ independently is hydrogen or a group R²; and R² is a C₁_₂₀ hydrocarbyl group optionally interrupted by heteroatoms .

3. Use as claimed in claim 2 wherein at least one group A is of formula

wherein R³ is as hereinbefore defined.

4. Use as claimed in any one of claims 1 to 3 wherein said ligand is of formula (la)

R*-L" [A'-L-'J_nA'-L" [A²-L"]_pA²-L"-R* (la)

where R* , n and p are as hereinbefore defined; A¹ is a group of formula II as defined in claim 2 ; each A² independently is a group of formula II, or an M- coordinating η², η⁵, N or N^Θ; and each L" independently is a bridging group providing a 1, 2, 3 or 4 atom chain between the groups it connects.

5. Use as claimed in any one of claims 1 to 4 wherein n, m and p are zero.

6. Use as claimed in any one of claims 1 to 5 wherein said ligand is of formula III

where each R⁴ is H or - (CR⁵ ₂) _SNR⁵ ₂, - (CR⁵ ₂) _sN^θR⁵, or - (CR⁵ ₂) _tCR⁵=NR⁵, at least one R⁴ being other than H; s is 1, 2 or 3; t is 1 or 2 ; each R^s is hydrogen or a group R¹; R¹ is hydrogen or a C_x. ₂₀ hydrocarbyl group optionally interrupted by heteroatoms and optionally substituted by a group R²; X, R² and Z are as hereinbefore defined; and Y' is a carbene carbon or silicon atom.

7. Use as claimed in any one of claims 1 to 5 wherein R* is methyl, ethyl, C^-di or trialkylphenyl .

8. Use as claimed in claim 7 wherein the R* is 2,6- diisopropylphenyl or 2,4, 6-trimethvlrhenvl .

9. Use as claimed in any one of claims 1 to 8 wherein at least one group A is of formula

\\_

10. Use as claimed in any one of claims 1 to 9 wherein at least one group A is a nitrogen atom and is linked to an adjacent atom by an imino linkage.

11. Use as claimed in any one of claims 1 to 10 wherein said ligand is of formula

wherein R* ' is methyl or 2 , 4 , 6-trimethylphenyl, R* ' ' is 2 , 6-diisopropylphenyl or 2 , 4 , 6-triisopropylphenyl , and L' is a 2 to 4 carbon atom linking group, the link to the non-ring nitrogen being via an imino bond.

12. Use as claimed in any one of claims 1 to 11 wherein said metal is silver, palladium, chromium, nickel, iron or cobalt.

13. The use of a complex of a group 3 to 10 transition metal or lanthanide with a ligand of formula IV

R3

Z= R6—X X—R6 (^IV)

(wherein each X is N or P; Z is N or CR³; and each R³ independently is hydrogen or a group R²,

R² is a C_x_₂₀ hydrocarbyl group optionally interrupted by heteroatoms,

Y¹ is a carbene carbon or silicon atom; and each R⁶, which may be the same or different, is hydrogen or a group R² (as hereinbefore defined) or both R⁶ groups together form a group -CR³=CR³-, with the proviso that where R⁶ is hydrogen or a pendant R¹ group then either Y¹ is other than carbon or at least one X or Z is P) as an olefin polymerization catalyst or procatalyst .

14. An olefin polymerization catalyst system comprising (I) a complex as defined in any one of claims 1 to 12 or the reaction product thereof with a co-catalyst, optionally disposed within a porous particulate carrier and (II) a co-catalyst where said complex has not reacted therewith.

15. A process for olefin polymerization which process comprises polymerizing an α-olefin monomer, optionally together with at least one comonomer copolymerizable therewith, wherein as a catalyst is used a catalyst system as claimed in claim 14.

16. A process for the preparation of a complex as defined in any one of claims 1 to 12, said process comprising at least one of the following steps:

(A) metallating a ligand of formula I or IV with a group 3 to 10 transition metal or lanthanide;

(B) transmetallating a metal complex of a ligand of formula I or IV with a group 3 to 10 transition metal or lanthanide ; and

17. A ligand of formula I or IV or a salt or complex thereof .