TITLE OF INVENTION

Novel Late Transition Metal Catalysts for Selective Polymer Formation

BACKGROUND OF THE INVENTION

Historically, catalyst technology for the polymerisation of olefins (e.g., polystyrene: PS) began with the use of inorganic halides (Ziegler-Natta polymerisation) as the homogeneous metal catalyst(s). These early systems, although quite effective, have certain disadvantages that have led to the continued exploration of new catalyst designs. One disadvantage of the early polymer catalysts is their low-selectivity for specific polymer architectures (e.g., syndiotactic-PS: sPS [N. Tomotsu, N. Ishihara, T.H. Newman, M.T. Malanga, J. Molec. Catal. A: Chemical, 1998, 128, 167-190] versus atactic- and/or isotactic-PS [J. Boor, "Ziegler-Natta Catalysts & Polymerizations" , Academic Press, 1979]. By the 1980s, cyclopentadiene (Cp) based catalysts (notably of Ti and Zr) began to move to the forefront of the developed technologies due to their high polymerisation activity and greatly improved selectivity [Z. Guan, Chem. Asian J., 2010, 5, 1058-1070; E.Y.-X. Chen, Chem. Rev., 2009, 109, 5157-5214]. These early transition metal (TM) systems are highly air-sensitive [N. Matsukawa, S.-I. Ishii, R. Furuyama, J. Saito, M. Mitani, H. Makio, H. Tanaka, T. Fujita, e-Polymers, 2003, 021, 1-25] [G. Odian, "Principles of Polymerization, 4 ^th Ed.", 2004, Ch. 8]. Attempted improvements to the technology have led to late transition metal (e.g., Ni) non-Cp systems being the subject of intense scrutiny. The first successful of these are the Shell Higher Olefin Process (SHOP) catalysts which show moderate activity for the production of polymers [K. J. Klabunde, J. Molec. Catal., 1987, 41, 123-134]. A wide variety of other second generation systems have since appeared [R. Grubbs, Science, 2000, 287, 460-462] which almost invariably require the incorporation of bulky ligands to impart useful catalytic activity; such ligands can often only be produced via multi-step syntheses, which may be costly. In addition, the use of large amounts (e.g., >50 fold excesses) of activators such as alkyl-lithiums or alkyl-aluminum polymers (e.g., MethylAluminOxane ("MAO") is usually a requirement. MAO is made by the hydrolysis of trimethylaluminum "TMA" and TMA is an expensive raw material. Furthermore, operating temperatures higher than room temperature are also necessary to give economically attractive polymerisation kinetics.

Stereoregular polymers such as sPS are currently marketed by a number of companies of which Idemitsu Kosan of Japan is an example of a primary world supplier of sPS under the tradename XAREC®; there is good market potential for this robust and recyclable {i.e., environmentally friendly) form of PS. Current technology for sPS production uses high concentrations of MAO together with an air-sensitive Zirconium- based catalyst system [see: Macromolecules, 1986, 19, 2464-6 & 1988, 21, 3356-60].

Metal clusters, a class of inorganic compounds typically characterised by a combination of a small number (typically under eight) of metal atoms linked by metal- metal bonds and/or ligands, were developed extensively in the 1970s and 1980s. Some examples of prototypical metal clusters include Ru ₃ (CO)i ₂ , the [Mo ₆ Cl ₈ ] ⁴⁺ cation, Rh (CO)i ₆ and the hydride complex H ₃ Ni ₃ Cp ₃ . Metal clusters have found considerable utility in hydrogenation chemistry but have rarely been evaluated for their polymerisation activity [G. Stiss-Fink, G. Meister, Adv. Organomet. Chem., 1993, 35, 41-134] and even less so for the production of stereospecific polymer architectures such as syndio-tactic or syndio-tactic rich polymers.

Syndio-tactic polymers are not typically produced via late transition metal catalysis [e.g., E.Y.-X. Chen, Dalton Trans., 2009, 8784-8793; N. Tomotsu, N. Ishihara, T.H. Newman, M.T. Malanga, J. Molec. Catal. A: Chemical, 1998, 128, 167-190]. Nickel-based catalytic systems have been previously exploited for the production of non- stereo-specific and/or non-syndio-tactic polymer architectures [L.C. Ferreira, M.A.S. Costa, M.R.M.P. Aguiar, P.I.C. Guimaraes, L.C. de Santa Maria, Polymer Bull., 2002, 48, 463-468; M.L. Dias, G.L. Crossetti, C. Bormioli, A. Giarusso, L.C. de Santa Maria, F.M.B. Coutinho, L. Porri, Polymer Bull, 1998, 40, 689-694; F.M.B. Coutinho, L.F. Monteiro, M.A.S. Costa, L.C. de Santa Maria, S.M.C. Menezes, Polymer Bull, 1998, 40, 423-429; C. Carlini, A.M. Raspolli Galletti, G. Sbrana, D. Caretti, Polymer, 2001, 42, 5069-5078; L.C. Ferreira, Jr., M.A.S. Costa, P.I.C. Guimaraes, L.C. de Santa Maria, Polymer, 2002, 43, 3857-3862; L.F. Groux, D. Zargarian, Organometallics, 2001, 20, 381 1-3817; C. Carlini, A. Macinai, A.M. Raspolli Galletti, G. Sbrana, Macromol. Symp., 2004, 213, 209-220; X. Mi, Z. Ma, L. Wang, Y. Hu, Macromol. Chem. Phys., 2003, 204, 868-876; R.S. Mauler, R.F. de Souza, D.V.V. Vesccia, L.C. Simon, Macromol. Rapid Commun., 2000, 21, 458-463; J.R. Ascenso, A.R. Dias, P.T. Gomes, C.C. Romao, I. Tkatchenko, A. Revillon, Q.-T. Pham, Macromolecules, 1996, 29, 4172-4179; K. Endo, Y. Yamanaka, Macromol. Rapid Commun., 2000, 21, 785-787; P. Longo, F. Grisi, A. Proto, A. Zambelli, Macromol. Rapid Commun., 1998, 19, 31-34; G.L. Crosetti, C. Bormioli, A. Ripa, A. Giarrusso, L. Porri, Macromol. Rapid Commun., 1997, 18, 801- 808; C. Pellecchia, A. Zambelli, Macromol. Rapid Commun., 1996, 17, 333-338; M. Jimenez-Tenorio, M.C. Puerta, I. Salcedo, P. Valerga, S.I. Costa, L.C. Silva, P.T. Gomes, Organometallics, 2004, 23, 3139-3146; R. Po, N. Cardi, R. Santi, A.M. Romano, C. Zannoni, S. Spera, J. Polym. Sci. A: Polym. Chem., 1998, 36, 21 19-2126; F. Peruch, H. Cramail, A. Deffieux, Macromol. Chem. Phys., 1998, 199, 2221-2227; K. Endo, Macromol. Chem. Phys., 1999, 200, 1722-1725; H. Gao, Y. Chen, F. Zhu, Q. Wu, J. Polym. Sci. A: Polym. Chem., 2006, 44, 5237-5246; A. Koppl, H.G. Alt, J. Molec. Catal. A: Chemical, 2000, 154, 45-53; P. Longo, A. Giulia Amendola, F. Grisi, A. Proto, Macromol. Chem. Phys., 1999, 200, 2461-2466; S. Yu, X. He, Y. Chen, Y. Liu, S. Hong, Q. Wu, J Appl. Polym. Sci., 2007, 105, 500-509; H. Sun, W. Li, X. Han, Q. Shen, Y. Zhang, J. Organomet. Chem., 2003, 688, 132-137; J. Li, M. Li, S. Li, L. Shi, C. Ren, D. Cui, Y. Wang, T. Tang, J Polym. Sci. A: Polym. Chem., 2008, 46, 1240-1248; H. Sun, Q. Shen, M. Yang, Eur. Polym. J, 2002, 38, 2045-2049; C.-T. Zhao, M. do Rosario Ribeiro, M. Farinha Portela, S. Pereira, T. Nunes, Eur. Polym. J., 2001, 37, 45-54; X. He, Y. Chen, Y. Liu, M. Chen, S. Yu, S. Hong, Q. Wu, e-Polymers, 2008, 083, 1-12; Y. Li, M. Gao, Q. Wu, Appl Organomet. Chem., 2008, 22, 659-663; CM. Killian, DJ. Tempel, L.K. Johnson, M. Brookhart, J Am. Chem. Soc, 1996, 118, 1 1664-1 1665; G.R. Tang, G.X. Jin, Chin. Sci. Bull., 2008, 53, 2764-2769; L.K. Johnson, CM. Killian, M. Brookhart, J. Am. Chem. Soc, 1995, 117, 6414-6415; H. Gao, L. Pei, K. Song, Q. Wu, Eur. Polym. J, 2007, 43, 908-914; M. Bialek, H. Cramail, A. Deffieux, S.M. Guillaume, Eur. Polym. J, 2005, 41, 2678-2684].

Nickel catalysts for the polymerisation of styrene usually result in either an atactic polystyrene (aPS) or an isotactic-rich aPS (J. Schellenberg. Prog. Polym. Sci., 2009, 34, 688-718). A syndiotactic-rich aPS has been obtained by Groux et al. in 2001 using a nickel compound containing a chelating amino-indenyl ligand. The polymerisation is carried out at 80°C with a silver halide catalyst and 2 d reaction time. The molecular weight (M _w ) of this PS was 77,338 Daltons with a polydispersity index (PDI) of 3.15 (L. F. Groux, D. Zargarian, Organometallics. 2001, 20, 3811-3817).

Many nickel compounds along with a large MAO excess have been reported to polymerize MMA usually producing syndio-rich but broad PDI (>2) pMMA (E. Y.-X. Chen, Chem. Rev. 2009, 109, 5157-5214).

Therefore, it would be advantageous to have a polymerisation process in which said process can be carried out at lower temperatures and ambient pressure resulting in a substantially syndio-tactic rich polymer exhibiting a substantially high M _w and a narrow substantially PDI.

Due to the industrial and domestic importance of polymers, including polymers such as sPS [M. van Heeringen, B. Vastenhout, R. Koopmans, L. Aerts, e-Polymers, 2005, 048, 1-3; E.Y.-X. Chen, Dalton Trans., 2009, 8784-8793], there remains a need for the development of improved nickel based catalyst technologies. In relation to the production of syndiotactic polymer architectures, preferably systems exhibiting at least one of the following characteristics are preferable: good selectivity, low cost, reduced [MAO] / [pre-catalyst] ratios and atmospheric stability with protocols that have improved energy efficiency (i.e. polymerisations can be conducted at room temperature and normal atmospheric pressure) and are therefore substantially more environmentally benign [R. Grubbs, Science, 2000, 287, 460^*62], and yield substantially high Mw and substantially narrow PDI polymer products.

Killian et al, [J Am. Chem Soc. 1996, 118, 1 1664-1 1665] describes the development of a procedure for living polymerisation of a-olefins based on nickel-a- diimine catalysts. There is no mention of syndiotactic end products.

Ascenso et al, [Macromolecules 1996, 29, 4172-4179] describes the oligomerisation of isotactic styrenics with a nickel phosphine-complex.

E. Zangrando et al. (Eur. J. Inorg. Chem., 2003, 2683-2692) discusses the synthesis and characterization of nickel(II) and cobalt(III) complexes containing a 2- (arylimino)-3-(hydroxyimino)butane ligand. Preliminary test polymerizations of methylmethacrylic acid in THF solvent were carried out on a cobalt(III) complex containing the (E,E)-2-(o-tolylimino)-3-(hydroxyimino)butane ligand using AIBN activator. AIBN alone gives a higher molecular weight polymer but the cobalt(III) complex activated with AIBN gives a polymer with a lower polydispersity.

A general discussion on syndiotactic polystyrene is found in "Syndiotactic Polystyrene" by J. Schellenberg (Editor), Wiley & Sons, Hoboken, 2010.

The following details the application of trinuclear nickel halide clusters as air- stable, pre-catalysts in the polymerisation of vinyl and alkyne monomers, including polar and apolar monomers to yield stereo-regular polymers, preferably substantially syndiotactic polymers.

SUMMARY OF THE INVENTION

According to one aspect of the invention there is provided a novel active cluster catalyst system useful for the polymerisation of vinyl and alkyne based monomers.

According to another aspect of the invention there is provided a process to manufacture nickel based active cluster catalyst systems.

According to another aspect of the invention there is provided a polymerisation process comprising the use of a nickel based active cluster catalyst systems, preferably said catalyst system is tri-nuclear nickel based, which has reduced activator

consumption, preferably reduced activator consumption of an alkylaluminoxane, preferably MethylAluminOxane.

According to another aspect of the invention there is provided an improved polymerisation process, incorporating said nickel based active cluster catalyst system.

According to yet another aspect of the invention there is provided a transition metal based cluster useful as a catalyst in the polymerisation of vinyl and alkyne based monomers.

According to still another aspect of the invention there is provided polymers of vinyl and alkyne based monomers, whenever produced by said process, preferably polystyrene, polymethacrylate and polymethylmethacrylate.

According to yet another aspect of the invention there is provided the preparation of an active, stereoregular olefin polymerisation transition metal cluster catalyst, preferably said transition metal is nickel. Preferably said preparation comprises the reaction of a transition metal cluster pre-catalyst of the formula [μ ₃ -(Α)-μ ₃ -(Β)-{μ-(Χ) ₃ - (NiL) ₃ }]C (1: A, C and X = CI, B=OH, L = tmeda or 2: A, C and X=C1, B=OH, L = 4,4- dimethyl-2-(o-anilinyl)-2-oxazoline or 3: A, C and X =Br, B=OH, L =4,4-dimethyl-2-(o- anilinyl)-2-oxazoline) and an alkylaluminoxane, preferably MethylAluminOxane (MAO). The ratio of the transition metal cluster pre-catalyst to alkylaluminoxane is from between about 1 : 1 to about 1 :6 equivalents, most preferably the ratio is 1 :1 equivalents.

According to yet another aspect of the invention, the active cluster catalyst system is suitable for the stereoregular, preferably substantially syndiotactic polymerisation of a variety of vinyl and alkyne monomers, such as olefin starting materials including but not limited to ethylene, propylene, other alkylvinyls, aryl vinyls including styrenics, methacrylates, acrylates, dienes, vinylhalides and the like, preferably the vinyl monomers styrene and methylmethacrylate, acetylene and alkyl or di-alkyl acetylenes.

Preferably, the polymerisation of monomers and the preparation of the active cluster catalyst system is carried out at substantially low temperatures, preferably between about 0°C to a temperature that substantially reduces the tendency of the monomer to undergo auto-polymerisation, most preferably at ambient temperature or 25°C.

Preferably, the polymerisation of monomers and the active cluster catalyst is carried out at substantially low pressures, preferably between about 1 to about 100 psi, most preferably at ambient atmospheric pressure.

In one embodiment, the polymerisations are carried out in bulk or in at least one organic solvent, preferably a non-polar aprotic solvent, most preferably toluene.

In another embodiment, the polystyrene, polymethacrylate and polymethylmethacrylate whenever produced from the reaction comprising styrene, methacrylate and methylmethacrylate, respectively, and the above mentioned active cluster catalyst system are of substantially high molecular weight, preferably in the range of between about 10,000 to about 1 ,000,000 Daltons.

In another embodiment, the polystyrene, polymethacrylate and polymethylmethacrylate whenever produced from the reaction comprising styrene, methacrylate and methylmethacrylate, respectively, and the above mentioned active cluster catalyst system have substantially low polydispersity indexes, preferably between about 1.0 to about 2.5. In another embodiment, the polystyrene, polymethacrylate and polymethylmethacrylate whenever produced from the reaction comprising styrene, methacrylate and methylmethacrylate, respectively, and the abovementioned active cluster catalyst system are substantially syndiotactic, preferably at least 65% syndiotactic in nature.

Preferably said cluster is substantially air stable.

Preferably said cluster is nickel based.

Preferably said nickel is tri-nuclear.

In another embodiment, there is provided a process for preparing a substantially stereo-regular polymer, from a vinyl or alkyne monomer, comprising activating said monomer with an effective amount of a trinuclear transition metal cluster in the presence of an aluminum based activator for an effective amount of time to initiate polymerisation at a temperature in the range of about 0°C to a temperature that substantially reduces the tendency of the monomer to undergo auto-polymerisation, preferably at room temperature, more preferably at about 25°C.

In another embodiment, there is provided a process for preparing a substantially stereo-regular polymer, from a vinyl or alkyne monomer, comprising activating said monomer with an effective amount of a trinuclear transition metal cluster in the presence of an aluminum based activator for an effective amount of time to initiate polymerisation at a pressure in the range of from 1 to about 100 psi, preferably at ambient atmospheric pressure, more preferably at 14.7 psi.

In another embodiment there is provided a stereo-regular polymer whenever produced by a process comprising the use of a tri-nuclear transition metal cluster.

Preferably said polymer is selected from the group consisting of polystyrene, polymethylacrylate and polymethylmethacrylate.

Preferably said polymer is substantially syndiotactic.

In another embodiment, there is provided a process for preparing a stereo-regular polymer comprising: contacting an olefin monomer with a trinuclear nickel based catalyst and an activator. According to yet another aspect of the invention, there is provided an active catalyst system, that is a reaction product of: a) a nickel cluster of the general formula

[μ ₃ -(Α)-μ ₃ -(Β)-{μ-(Χ) ₃ -(ΝΐΙ.) ₃ }^ wherein A and B are independently selected from halogen or hydroxyl; preferably said halogen is selected from the group consisting of chlorine, bromine and iodine;

X=halogen, preferably selected from the group consisting of chlorine, bromine and iodine

L-a primary, secondary and/or tertiary nitrogen based ligand, preferably an amine or imine based ligand, preferably selected from the group consisting of tetramethylethylenediamine, 1 ,2-(benzylamino)ethane and substituted 2-(o- anilinyl)-2-oxazoline, preferably said substituted 2-(o-anilinyl)-2-oxazoline is 4,4-dimethyl-2-(o-anilinyl)-2-oxazoline, a 2-(arylimino)-3- (hydroxyimino)alkane ligand; (E, E)-2-(phenylimino)-3 -(hydroxyimino)butane, (E,E)-2-[(2-isopropyl)phenylimino]-3-(hydroxyimino)butane, (E,E)-2-[(3,5- dimethyl)phenylimino]-3-(hydroxyimino)butane, (E,E)-2-(o-tolylimino)-3- (hydroxyimino)butane, (£,E)-2-[(2-t-butyl)phenylimino]-3- (hydroxyimino)butane, (E,E)-2-{(2,4,6-trimethyl)phenylimino]-3- (hydroxyimino)butane, (E,E)-2-(p-tolylimino)-3-(hydroxyamino), (E,E)-2- [(2,6-dimethyl)phenylimino)-3-(hydroxyimino)butane, (E,E)-2-[(2,6- diisopropyl)phenylimino]-3-(hydroxyimino)butane, 2-(2-methyl-3- chlorophenylimino)-3 -(2-methyl-3 -chlorophenylimino)butane, 2-(2-methy 1-4- chlorophenylimino)-3-(2-methyl-4-chlorophenylimino)butane, 2-(2-methyl-5- chlorophenylimino)-3-(2-methyl-5-chlorophenylimino)butane, 2-(2-methyl-3- chlorophenylimino)-3-(2-methyl-3-chlorophenylimino)pentane, 2-(2-methyl-4- chlorophenylimino)-3-(2-methyl-4-chlorophenylimino)pentane, 2-(2-methyl-5- chlorophenylimino)-3-(2-methyl-5-chlorophenylimino)pentane, 3-(2-methyl-3- chlorophenylimino)-4-(2-methyl-3-chlorophenylimino)hexane, 3-(2-methyl-5- chlorophenylimino)-4-(2-methyl-5-chlorophenylimino)hexane, 3-(2-chloro-4- methylphenylimino)-4-(2-chloro-4-methylphenylimino)hexane, 1 -(2-methyl-3 - chlorophenylimino)-2-(2-methyl-3-chlorophenylimino)- 1 ,2-diphenylethane, 1 - (2-methyl-4-chlorophenylimino)-2-(2-methyl-4-chlorophenylimi no)- 1 ,2- diphenylethane, 1 -(2-methyl-5-chlorophenylimino)-2-(2-methyl-5- chlorophenylimino)-l,2-diphenylethane, and l-(2-chloro-4- methylphenylimino)-2-(2-chloro-4-methylphenylimino)-l,2-diph enylethane; and

C=hydroxyl, halogen, preferably said halogen is selected from the group consisting of chlorine, bromine and iodine or a pseudo-halogen counter ion, said pseudo- halogen is preferably selected from the group consisting of triiodide, thiocyanate, isothiocyanate, cyanide, perchlorate, hexafluorophosphate, tetrafluoroborate, tetraphenylborate, antimonyhexafluoride and the like; and b) an D-aluminoxane, wherein D=alkyl, preferably said alkyl is selected from the group consisting of alkyl group, preferably methyl; wherein said reaction is optionally conducted in an aprotic solvent, preferably a non-polar aprotic solvent, preferably toluene, under a substantially moisture-free and oxygen-free environment, preferably under an argon or nitrogen environment, most preferably under a nitrogen environment. In one instance, A, C and X are independently selected from chlorine, bromine or iodine, L=tetramethylethylenediamine, 1 ,2-(benzylamino)ethane or 4,4-dimethyl-2-(o- anilinyl)-2-oxazoline, B=hydroxyl and D=methyl.

In another instance, A, C and X=chlorine, L- tetramethylethylenediamine, B=hydroxyl and D=methyl.

In another instance, A, C and X=chlorine, L=4,4-dimethyl-2-(o-anilinyl)-2- oxazoline, B=hydroxyl and D=methyl.

In another instance, A, C and X=bromine, L=4,4-dimethyl-2-(o-anilinyl)-2- oxazoline, B=hydroxyl and D=methyl.

According to yet another aspect of the invention, there is provided a method for preparing an active catalyst in situ comprising the steps of: a) providing a nickel cluster of the general formula

[μ ₃ -(Α)-μ ₃ -(Β)-{μ-(Χ) ₃ -(ΝΐΙ,) ₃ }^ wherein A, B are independently selected from halogen or hydroxyl; preferably said halogen is selected from the group consisting of chlorine, bromine and iodine;

X=halogen, preferably selected from the group consisting of chlorine, bromine and iodine

L=a primary, secondary and/or tertiary nitrogen based ligand, preferably an amine or imine based ligand, preferably selected from the group consisting of tetramethylethylenediamine, l,2-(benzylamino)ethane and substituted 2-(o- anilinyl)-2-oxazoline, preferably said substituted 2-(o-anilinyl)-2-oxazoline is 4,4-dimethyl-2-(o-anilinyl)-2-oxazoline, a 2-(arylimino)-3- (hydroxyimino)alkane ligand; (E, E)-2-(phenylimino)-3-(hydroxyimino)butane, (£ ^, ,£T)-2-[(2-isopropyl)phenylimino]-3-(hydroxyimino)but ane, (E,E)-2-[(3,5- dimethyl)phenylimino]-3-(hydroxyimino)butane, (E,E)-2-(o-tolylimino)-3- (hydroxyimino)butane, (E,E)-2-[(2-t-butyl)phenylimino]-3- (hydroxyimino)butane, (E,E)-2-{(2,4,6-trimethyl)phenylimino]-3- (hydroxyimino)butane, (E, E)-2-(p-tolylimino)-3 -(hydroxyamino), (E, E)-2- [(2,6-dimethyl)phenylimino)-3-(hydroxyimino)butane, (E,E)-2-[(2,6- diisopropyl)phenylimino]-3-(hydroxyimino)butane, 2-(2-methyl-3- chlorophenylimino)-3-(2-methyl-3-chlorophenylimino)butane, 2-(2-methyl-4- chlorophenylimino)-3-(2-methyl-4-chlorophenylimino)butane, 2-(2-methyl-5- chlorophenylimino)-3-(2-methyl-5-chlorophenylimino)butane, 2-(2-methyl-3- chlorophenylimino)-3-(2-methyl-3-chlorophenylimino)pentane, 2-(2-methyl-4- chlorophenylimino)-3-(2-methyl-4-chlorophenylimino)pentane, 2-(2-methyl-5- chlorophenylimino)-3-(2-methyl-5-chlorophenylimino)pentane, 3-(2-methyl-3- chlorophenylimino)-4-(2-methy]-3-chlorophenylimino)hexane, 3-(2-methyl-5- chlorophenylimino)-4-(2-methyl-5-chlorophenylimino)hexane, 3-(2-chloro-4- methylphenylimino)-4-(2-chloro-4-methylphenylimino)hexane, l-(2-methyl-3- chlorophenylimino)-2-(2-methyl-3 -chlorophenylimino)- 1 ,2-diphenylethane, 1 - (2-methyl-4-chlorophenylimino)-2-(2-methyl-4-chlorophenylimi no)-l,2- diphenylethane, 1 -(2-methyl-5-chlorophenylimino)-2-(2-methyl-5- chlorophenylimino)-l,2-diphenylethane, and l-(2-chloro-4- methylphenylimino)-2-(2-chloro-4-methylphenylimino)-l,2-diph enylethane; and

C=hydroxyl, halogen, preferably selected from the group consisting of chlorine and bromine or a pseudo-halogen counter ion, preferably selected from the group consisting of triiodide, thiocyanate, isothiocyanate, cyanide, perchlorate,

hexafluorophosphate, tetrafluoroborate, tetraphenylborate, antimonyhexafluoride and the like; and b) providing an D-aluminoxane, wherein D=alkyl, preferably selected from the group consisting of Ci-C ₆ alkyl group, more preferably methyl

c) optionally in the presence of an aprotic solvent, preferably a non-polar aprotic solvent, more preferably toluene,

d) stirring for at least a period of time to result in a change in colour of said reaction, preferably for a period of time from about 5 minutes to about 10 minutes, under a substantially moisture-free and oxygen-free environment. According to yet another aspect of the invention, there is provided a catalyst system for use in the polymerisation of vinyl and alkyne based monomers, said system comprising the reaction of

[μ3-(Α)-μ ₃ -(Β)-{μ-(Χ)3-(Ν^)3}]0 wherein A, B=halogen or hydroxyl; preferably said halogen is selected from the group consisting of chlorine, bromine and iodine;

X=halogen, preferably selected from the group consisting of chlorine, bromine and iodine

L=a primary, secondary and/or tertiary nitrogen based ligand, preferably an amine or imine based ligand preferably selected from the group consisting of tetramethylethylenediamine, 1 ,2-(benzylamino)ethane and substituted 2-(o- anilinyl)-2-oxazoline, preferably said substituted 2-(o-anilinyl)-2-oxazoline is 4,4-dimethyl-2-(o-anilinyl)-2-oxazoline, a 2-(arylimino)-3- (hydroxyimino)alkane ligand; (EE)-2-(phenylimino)-3-(hydroxyimino)butane, (£,E)-2-[(2-isopropyl)phenylimino]-3-(hydroxyimino)butane, (E,E)-2-[(3,5- dimethyl)phenylimino]-3-(hydroxyimino)butane, (E,E)-2-(o-tolylimino)-3- (hydroxyimino)butane, (E,£)-2-[(2-t-butyl)phenylimino]-3- (hydroxyimino)butane, (E,£)-2-{(2,4,6-trimethyl)phenylimino]-3- (hydroxyimino)butane, (E£)-2-(p-tolylimino)-3-(hydroxyamino), (E,E)-2- [(2,6-dimethyl)phenylimino)-3-(hydroxyimino)butane, (EE)-2-[(2,6- diisopropyl)phenylimino]-3-(hydroxyimino)butane, 2-(2-methyl-3- chlorophenylimino)-3-(2-methyl-3-chlorophenylimino)butane, 2-(2-methyl-4- chlorophenylimino)-3-(2-methyl-4-chlorophenylimino)butane, 2-(2-methyl-5- chlorophenylimino)-3 -(2-methyl-5 -chlorophenylimino)butane, 2-(2-methyl-3 - chlorophenylimino)-3 -(2-methyl-3 -chlorophenylimino)pentane, 2-(2 -methyl -4- chlorophenylimino)-3-(2-methyl-4-chlorophenylimino)pentane, 2-(2-mefhyl-5- chlorophenylimino)-3 -(2-methyl-5 -chlorophenylimino)pentane, 3 -(2-methyl-3 - chlorophenylimino)-4-(2-methyl-3-chlorophenylimino)hexane, 3-(2-methyl-5- chlorophenylimino)-4-(2-methyl-5-chlorophenylimino)hexane, 3-(2-chloro-4- methylphenylimino)-4-(2-chloro-4-methylphenylimino)hexane, 1 -(2-methyl-3 - chlorophenylimino)-2-(2-methyl-3 -chlorophenylimino)- 1 ,2-diphenyl ethane, 1 - (2-methyl-4-chlorophenylimino)-2-(2-methyl-4-chlorophenylimi no)-l,2- diphenylethane, 1 -(2-methyl-5-chlorophenylimino)-2-(2-methyl-5- chlorophenylimino)-l,2-diphenylethane, and 1 -(2-chloro-4- methylphenylimino)-2-(2-chloro-4-methylphenylimino)-l ,2-diphenylethane; and

C=hydroxyl, halogen, preferably selected from the group consisting of chlorine and bromine or a pseudo-halogen counter ion, preferably selected from the group consisting of triiodide, thiocyanate, isothiocyanate, cyanide, perchlorate,

hexafluorophosphate tetrafluoroborate, tetraphenylborate, antimonyhexafluoride and the like into a reactor, c) optionally introducing an aprotic solvent into the reactor, preferably a non-polar aprotic solvent, more preferably toluene,

d) introducing D-aluminoxane, wherein D=alkyl, preferably selected from the group consisting of Ci-C alkyl group, preferably methyl, into the reactor.

In another instance, the invention is useful for the polymerisation of vinyl and alkyne based monomers, said polymerisation results in a substantially syndiotactic polymer.

According to yet another aspect of the invention there is provided a process for polymerizing a vinyl or alkyne monomer comprising the steps of: a) introducing a nickel cluster of the general formula

[μ ₃ -(Α)-μ ₃ -(Β)-{μ-(Χ) ₃ -(ΝίΙ.) ₃ }]ΰ wherein A, B=halogen or hydroxyl; preferably said halogen is selected from the group consisting of chlorine, bromine and iodine;

X=halogen, preferably selected from the group consisting of chlorine, bromine and iodine

L=a primary, secondary and/or tertiary nitrogen based ligand, preferably an amine or imine based ligand, preferably selected from the group consisting of tetramethylethylenediamine, 1 ,2-(benzylamino)ethane and substituted 2-(o- anilinyl)-2-oxazoline, preferably said substituted 2-(o-anilinyl)-2-oxazoline is 4,4-dimethyl-2-(o-anilinyl)-2-oxazoline, a 2-(arylimino)-3- (hydroxyimino)alkane ligand, preferably selected from (E,E)-2-(phenylimino)- 3 -(hydroxyimino)butane, (E, E)-2-[(2-isopropyl)phenylimino] -3 - (hydroxyimino)butane, (E,E)-2-[(3,5-dimethyl)phenylimino]-3- (hydroxyimino)butane, (EE)-2-(o-tolylimino)-3-(hydroxyimino)butane, (E,E)- 2-[(2-t-butyl)phenylimino]-3-(hydroxyimino)butane, (E£)-2-{(2,4,6- trimethyl)phenylimino]-3-(hydroxyimino)butane, (E,E)-2-(p-tolylimino)-3- (hydroxyamino), (E£)-2-[(2,6-dimethyl)phenylimino)-3-(hydroxyimino)butane and (E,E)-2-[(2,6-diisopropyl)phenylimino]-3-(hydroxyimino)butan e; and C=hydroxyl, halogen, preferably selected from the group consisting of chlorine and bromine or a pseudo-halogen counter ion, preferably selected from the group consisting of triiodide, thiocyanate, isothiocyanate, cyanide, perchlorate,

hexafluorophosphate, tetrafluoroborate, tetraphenylborate, antimonyhexafluoride and the like into a reactor,

b) introducing the monomer into the reactor,

c) optionally introducing an aprotic solvent into the reactor, preferably a non-polar aprotic solvent, preferably toluene,

d) introducing D-aluminoxane, wherein D=alkyl, preferably selected from the group consisting of Cj-Q alkyl group preferably methyl, into the reactor,

e) maintaining the reactor under polymerisation conditions, preferably under an argon environment, most preferably under a nitrogen environment, and

f) retrieving the polymer. Preferably said polymer is substantially syndiotactic.

Preferably X is a halogen selected from the group consisting of chlorine, bromine and iodine.

Preferably L is an amine or amino based ligand selected from the group consisting of tetramethylethylenediamine, 1 ,2-(benzylamino)ethane, a 2-(arylimino)-3- (hydroxyimino)alkane ligand, preferably selected from (EE)-2-(phenylimino)-3- (hydroxyimino)butane; (E, E)-2- [(2-isopropyl)phenylimino] -3 -(hydroxyimino)butane, (E,E)-2-[(3,5-dimethyl)phenylimino]-3-(hydroxyimino)butane, (£,E)-2-(o-tolylimino)-3- (hydroxyimino)butane, (E,E)-2-[(2-t-butyl)phenylimino]-3-(hydroxyimino)butane, (E,E)- 2-{(2,4,6-trimethyl)phenylimino]-3-(hydroxyimino)butane, (E,E)-2-(p-tolylimino)-3- (hydroxyamino), (EE)-2-[(2,6-dimethyl)phenylimino)-3-(hydroxyimino)butane and (E,E)-2-[(2,6-diisopropyl)phenylimino]-3-(hydroxyimino)butan e, 2-(2-methyl-3- chlorophenylimino)-3-(2-methyl-3-chlorophenylimino)butane, 2-(2-methyl-4- chlorophenylimino)-3-(2-methyl-4-chlorophenylimino)butane, 2-(2-methyl-5- chlorophenylimino)-3-(2-methyl-5-chlorophenylimino)butane, 2-(2-methyl-3- chlorophenylimino)-3-(2-methyl-3-chlorophenylimino)pentane, 2-(2-methyl-4- chlorophenylimino)-3-(2-methyl-4-chlorophenylimino)pentane, 2-(2-methyl-5- chlorophenylimino)-3-(2-methyl-5-chlorophenylimino)pentane, 3-(2-methyl-3- chlorophenylimino)-4-(2-methyl-3-chlorophenylimino)hexane, 3-(2-methyl-5- chlorophenylimino)-4-(2-methyl-5 -chlorophenylimino)hexane, 3 -(2-chloro-4- methylphenylimino)-4-(2-chloro-4-methylphenylimino)hexane, l-(2-methyl-3- chlorophenylimino)-2-(2-methyl-3-chlorophenylimino)-l,2-diph enyl ethane, l-(2-methyl- 4-chlorophenylimino)-2-(2-methyl-4-chlorophenylimino)-l ,2-diphenylethane, 1 -(2- methyl-5-chlorophenylimino)-2-(2-methyl-5-chlorophenylimino) - 1 ,2-diphenylethane, and 1 -(2-chloro-4-methylphenylimino)-2-(2-chloro-4-methylphenylim ino)- 1 ,2- diphenylethane and substituted 2-(o-anilinyl)-2-oxazoline, preferably said substitution is 4,4-dimethyl.

Preferably Y is a halogen selected from the group consisting of chlorine, bromine and iodine.

In another instance Y is a pseudo halogen counter ion selected from the group consisting of triiodide, isothiocyanate, thiocyanate, cyanide, perchlorate,

hexafluorophosphate, tetraphenylborate, tetrafluoroborate, antimonyhexafluoride.

Preferably D is an alkyl selected from Ci-C ₆ alkyl group, preferably methyl. Preferably X=chlorine or bromine, L=tetramethylethylenediamine, 1 ,2-

(benzylamino)ethane, or 4,4-dimethyl-2-(o-anilinyl)-2-oxazoline, Y=hydroxyl and D=methyl.

In another instance X=chlorine, L= tetramethylethylenediamine, Y=hydroxyl and D=methyl.

In another instance X=chlorine, L=4,4-dimethyl-2-(o-anilinyl)-2-oxazoline,

Y=hydroxyl and D=methyl.

In another instance X=bromine, L=4,4-dimethyl-2-(o-anilinyl)-2-oxazoline, Y=hydroxyl and D=methyl.

Preferably, in any of the above, the nickel cluster and the D-aluminoxane is present in a ratio from about 1 : 1 to about 1 :6 equivalents respectively, more preferably the ratio is 1 : 1.

Preferably, in any of the above, said process is conducted at a temperature range of from 0°C to a temperature that substantially reduces the tendency of the monomer to undergo auto-polymerisation, preferably said temperature is about 25°C. Preferably, in any of the above, said process is conducted at a pressure range of from 1 to 100 psi, more preferably said pressure is ambient atmospheric pressure, most preferably 14.7 psi.

Preferably, in any of the above, said vinyl or alkyne monomer is selected from styrene, methacrylate and methylmethacrylate.

Preferably said nickel cluster and D-aluminoxane are present in a ratio of about 1 : 1 to about 1 :6 equivalents respectively, more preferably said ratio is 1 : 1.

More preferably said polymer is at least 60% syndiotactic.

Preferably said polymer has a molecular weight from about 10,000 to about 1 ,000,000 Daltons.

Preferably said polymer has a polydispersity index from about 1.0 to about 2.5.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 is an ORTEP representation of the cationic structural component of 1 of the present invention.

Figure 1 -A is an ORTEP representation of the cationic structural component of 2 of the present invention.

Figure 1-B is an ORTEP representation of the cationic structural component of 3 of the present invention.

Figure 1-C is a full ORTEP diagram with atomic numbering scheme of 3 of the present invention.

Figure 2 is the GPC results of polystyrene polymerized with crude 1 of the present invention with refractive index, viscometry and low angle light scattering peaks shown.

Figure 3 is the GPC results of polystyrene polymerized with 2 of the present invention with refractive index, viscometry and low angle light scattering peaks shown.

Figure 4 is the GPC results of polystyrene polymerized with crystalline 1 of the present invention with refractive index, viscometry and low angle light scattering peaks shown.

Figure 5 is the 1H NMR spectrum of polystyrene polymerized with crude 1 of the present invention. Figure 6 is the T _g of polystyrene polymerized with crude 1 of the present invention.

Figure 7 is the T _m of polystyrene polymerized with crude 1 of the present invention.

Figure 8 is the GPC results of polymethylmethacrylate polymerized with crystalline 1 of the present invention with refractive index, viscometry and low angle light scattering peaks shown.

Figure 9 is the increase of absolute M _w of polymethylmethacrylate polymerized with crystalline 1 over a five day reaction period, according to the present invention.

Figure 10 is the ^] H-NMR spectrum of polymethylmethacrylate polymerized with crystalline 1 according to the present invention.

Figure 1 1 is the T _g close up of polymethylmethacrylate polymerized with crystalline 1 according to the present invention.

Figure 12 is the FTIR spectrum of cross-linked polymethyacrylate polymerized with crystalline 1 according to the present invention.

DETAILED DESCRIPTION OF THE INVENTION

The following examples illustrate various aspects of the invention.

Confirmation of the Structure of {rNi^H^ ^C OHICl (1)

The basic structure of the {[Ni(C ₆ H ₁₆ N ₂ )] ₃ Cl ₄ OH}Cl (Figure 1) contains one bridging chloride connecting each Ni to one adjacent Ni atom for a total of three bridging chlorides and three Ni centres. Each Ni atom is distorted octahedral around its centre. A chloride atom and a hydroxide group are arranged one above and one below the plane formed by the Ni and bridging chloride atoms (i.e. "capping" groups). One tmeda ligand chelates each Ni in a ν^-Ν,Ν fashion. The hydrogen of the hydroxide group is found to be hydrogen bonded to a single chloride counteranion. The crystal structure data shows one coordinated DCM molecule per molecule of 1 which comes from the re- crystallization solvent. The structure of 1 was first reported in 1976 [U. Turpeinen, A. Pajunen, Finn. Chem. Lett., 1976, 6-1 1]. The data presented is of better accuracy than previously presented structures. The selected angles (Table, below) confirm that there is symmetry in the complex. Table 1 Selected bonds and angles of 1.

Selected Bond Lengths (A) Selected Bond Angles (°)

Ni(l)-Cl(l) 2.5429(56) Cl(2a)-Ni(l)-Cl(2) 163.59(6)

Ni(2c)-Cl(l) 2.5220(12) Cl(2a)-Ni(2c)-Cl(3) 162.79(4)

Ni(2)-Cl(l) 2.5220(12) Cl(3)-Ni(2)-Cl(2) 162.79(4)

Ni(l)-0(1) 2.050(4)

Ni(2c)-0(1) 2.028(3)

Ni(2)-0(1) 2.028(3)

Materials

Toluene was obtained from an M. Braun Solvent Purification System, dried using CaCl ₂ for 2 h and distilled under vacuum prior to use. Other solvents were used as purchased: dichloromethane (DCM: BDH, 99.5%), tetrahydrofuran (THF: EMD, 99.9%), methyl alcohol (MeOH: EMD, 98%), rc-hexane (EMD, 95%). Styrene and methyl methacrylate (MMA) monomers were purchased from Sigma-Aldrich, distilled prior to use and stored at -65°C. MAO was purchased from Sigma-Aldrich as a 10% wt. solution in toluene and used as is. NiCl ₂ -6H ₂ 0 (Alfa Aesar; 98%) was used as purchased. N,N, N, N-tetramethylethane-l,2-diamine (tmeda) was used as purchased (Sigma- Aldrich; 99%).

Characterization of the Polymers

All polymers prepared herein were dissolved in THF and characterized by gel permeation chromatography ("GPC") on a Viscotek GPCmax VE2001 GPC Solvent/Sample module against polystyrene broad and narrow standards using a triple detection system (Refractive Index, Light Scattering, Viscometer) for their absolute molecular weight (M _w ) and polydispersity index (PDI). Proton Nuclear Magnetic Resonance (1H-NMR) spectra were recorded on a Bruker Avance 11-400 spectrometer at 400 MHz and room temperature using chloroform-of (CDC1 ₃ ) (Sigma-Aldrich) as the solvent and internal standard. The thermal properties of the polymers, specifically the glass transition temperature (T _g ) and melting point (T _m ) were analyzed by differential scanning calorimetry (DSC) on a Perkin Elmer PYRIS Diamond Differential Scanning Calorimeter using a constant heating rate of 10°C/min.

Pre-catalyst cluster (1) [U. Turpeinen, A. Pajunen, Finn. Chem. Lett., 1976, 6-11) was prepared based on a method previously reported [D.A. Handley, P.B. Hitchcock, G.J. Leigh, Inorg. Chim. Acta, 2001, 314, 1-13] using 0.90 g (3.8 mmol) of NiCl ₂ -6H ₂ 0 and a 5 mL portion (33 mmol) of tetramethylethylene diamine which were added together in 125 mL of THF. The mixture was then heated to reflux temperature. A 0.83 g sample of a light green powder was isolated by filtration of the reaction mixture. (91.2 % yield based on Ni). To re-crystallize this material, the light green powder was dissolved in DCM and slowly layered with n-hexane. After one day, emerald coloured crystals were visible. Characterization of this material was carried out using IR spectroscopy. Decomposition of crystalline material was observed at 220°C. Its composition was confirmed by the single crystal X-ray diffraction study (k09121) below.

Table 1-1. Crystal data and structure for k09121 (catalyst 1).

Identification code k09121

Empirical formula C19 H51 C17 N6 Ni3 0

Formula weight 803.94

Temperature 150(2) K

Wavelength 0.71073 A

Crystal system Monoclinic

Space group C 2/m

Unit cell dimensions a = 16.9215(8) A oc= 90°.

b = 12.8791(6) A β= 1 13.207(2)°. c = 17.0089(8) A γ = 90°.

Volume 3406.9(3) A ³

Z 4

Density (calculated) 1.567 Mg/m ³

Absorption coefficient 2.214 mm- ¹

F(000) 1672

Crystal size 0.22 x 0.18 x 0.10 mm ³

Theta range for data collection 2.61 to 27.45°.

Index ranges -21 <=h<=21 , -15<=k<= 16, -22<=1<=22 Reflections collected 9384

Independent reflections 4007 [R(int) = 0.0521]

Completeness to theta = 27.45° 99.3 %

Absorption correction Semi-empirical from equivalents

Max. and min. transmission 0.828 and 0.720

Refinement method Full-matrix least-squares on F ²

Data / restraints / parameters 4007 / 0 / 193

Goodness-of-fit on F ² 1.051

Final R indices [I>2sigma(l)] Rl = 0.0487, wR2 = 0.1 125

R indices (all data) Rl = 0.0900, wR2 = 0.1383

Largest diff. peak and hole 0.939 and -0.946 e.A ^"3 Table 1-2. Atomic coordinates ( x 10 ⁴ ) and equivalent isotropic displacement parameters (A ² x 10 ³ ) for k09121. U(eq) is defined as one third of the trace of the orthogonahzed U« tensor.

X y z U(eq)

Ni(l) 1819(1) 0 4129(1) 19(1)

Ni(2) 667(1) 1179(1) 2550(1) 20(1)

Cl(l) 184(1) 0 3459(1) 24(1)

Cl(2) 1665(1) 1859(1) 3922(1) 26(1)

Cl(3) -226(1) 0 1404(1) 27(1)

Cl(4) 3133(1) 0 2255(1) 31(1)

0(1) 1529(3) 0 2840(2) 19(1)

N(l) 3190(3) 0 4704(3) 27(1)

N(2) 1889(3) 0 5414(3) 26(1)

N(3) 1069(2) 2113(3) 1740(2) 24(1)

N(4) -257(2) 2349(3) 2395(2) 26(1)

C(l) 3384(5) -319(6) 5617(5) 28(2)

C(2) 2801(5) 304(6) 5920(5) 27(2)

C(3) 3586(3) 916(4) 4496(4) 45(1)

C(4) 1498(4) -913(4) 5624(3) 50(2)

C(5) 361(3) 2886(4) 1381(3) 30(1)

C(6) 52(3) 3249(3) 2058(3) 30(1)

C(7) 1 171(3) 1535(4) 1033(3) 30(1)

C(8) 1889(3) 2661(4) 2220(3) 32(1)

C(9) -1 131(3) 2054(4) 1782(3) 36(1)

C(10) -345(3) 2676(4) 3199(3) 36(1)

Cl(5) -3042(1) -1 132(2) 109(1) 90(1)

C(l l) -2597(5) 0 -76(4) 35(2)

Table 1-3. Bond lengths [A] and angles [°] for k09121.

Ni(l)-0(1) 2.050(4)

Ni(l)-N(l) 2.133(5)

Ni(l)-N(2) 2.141(5)

Ni(l)-Cl(2)# l 2.4189( 10)

Ni(l)-Cl(2) 2.4189(10)

Ni(l)-Cl(l) 2.5429( 16)

Ni(2)-0(1) 2.028(3)

Ni(2)-N(4) 2.1 12(3)

Ni(2)-N(3) 2.132(3)

Ni(2)-Cl(2) 2.4409(11)

Ni(2)-Cl(3) 2.4640( 12)

Ni(2)-Cl(l ) 2.5220(12)

Cl(l)-Ni(2)#l 2.5220(12)

Cl(3)-Ni(2)# l 2.4640( 12)

0(1)-Ni(2)#l 2.028(3)

N(l)-C(3) 1.467(6)

N(l)-C(3)#l 1.467(6)

N(l)-C(l)# l 1.512(9)

N(l )-C(l) 1.512(9)

N(2)-C(4)#l 1.461(6)

N(2)-C(4) 1.461(6)

N(2)-C(2) 1.494(9)

N(2)-C(2)#l 1.494(9)

N(3)-C(7) 1.481(5)

N(3)-C(8) 1.482(5)

N(3)-C(5) 1.491(5)

N(4)-C(6) 1.478(5)

N(4)-C(9) 1.484(6)

N(4)-C(10) 1.494(6)

C(l)-C(2) 1.51 1(1 1)

C(5)-C(6) 1.513(6)

Cl(5)-C(l l ) 1.726(4)

C(1 1)-C1(5)#1 1.726(4) 0(1)-Ni(l)-N(l) 104.37(18)

0(1)-Ni(l)-N(2) 170.26(18)

N(l)-Ni(l)-N(2) 85.37(19)

0(1)-Ni(l )-Cl(2)#l 82.98(3)

N(l)-Ni( l)-Cl(2)#l 95.84(3)

N(2)-Ni(l)-Cl(2)#l 96.20(3)

0(1)-Ni(l)-Cl(2) 82.98(3)

N(l)-Ni(l )-Cl(2) 95.84(3)

N(2)-Ni(l)-Cl(2) 96.20(3)

Cl(2)#l-Ni(l)-Cl(2) 163.59(6)

0(1)-Ni(l)-Cl(l) 76.22(12)

N(l)-Ni(l)-Cl(l) 179.41(14)

N(2)-Ni(l )-Cl(l) 94.05(14)

Cl(2)#l -Ni(l)-Cl(l ) 84.22(3)

Cl(2)-Ni(l)-Cl(l ) 84.22(3)

0(1)-Ni(2)-N(4) 172.43(15)

0(1)-Ni(2)-N(3) 101.36(14)

N(4)-Ni(2)-N(3) 85.74(13)

0(1)-Ni(2)-Cl(2) 82.87(10)

N(4)-Ni(2)-Cl(2) 93.62(10)

N(3)-Ni(2)-Cl(2) 97.97(10)

0(1)-Ni(2)-Cl(3) 83.61(9)

N(4)-Ni(2)-Cl(3) 98.49(10)

N(3)-Ni(2)-Cl(3) 95.09(10)

Cl(2)-Ni(2)-Cl(3) 162.79(4)

0(1 )-Ni(2)-Cl( l) 77.07(1 1)

N(4)-Ni(2)-Cl( l) 95.94(10)

N(3)-Ni(2)-Cl(l) 177.17(10)

Cl(2)-Ni(2)-Cl(l) 84.22(4)

Cl(3)-Ni(2)-Cl(l) 82.42(4)

Ni(2)-Cl( l)-Ni(2)# l 74.06(4)

Ni(2)-Cl(l)-Ni(l) 73.53(4)

Ni(2)#l -Cl( l)-Ni(l) 73.53(4)

Ni(l)-Cl(2)-Ni(2) 77.19(4) Ni(2)-Cl(3)-Ni(2)#l 76.11(5)

Ni(2)#l-0(1)-Ni(2) 96.99(18)

Ni(2)#l-0(1)-Ni(l) 96.04(14)

Ni(2)-0(1)-Ni(l) 96.04(14)

C(3)-N(l)-C(3)#l 107.1(5)

C(3)-N(l)-C(l)#l 95.4(4)

C(3)#l-N(l)-C(l)#l 122.0(5)

C(3)-N(l)-C(l) 122.0(5)

C(3)#l-N(l)-C(l) 95.4(4)

C(l)#l-N(l)-C(l) 31.5(6)

C(3)-N(l)-Ni(l) 114.0(3)

C(3)#l-N(l)-Ni(l) 1 14.0(3)

C(l)#l-N(l)-Ni(l) 103.2(4)

C(l)-N(l)-Ni(l) 103.2(4)

C(4)#l-N(2)-C(4) 107.2(6)

C(4)#l-N(2)-C(2) 96.5(4)

C(4)-N(2)-C(2) 122.4(5)

C(4)#l-N(2)-C(2)#l 122.4(5)

C(4)-N(2)-C(2)#l 96.5(4)

C(2)-N(2)-C(2)#l 30.4(6)

C(4)#l-N(2)-Ni(l) 1 13.7(3)

C(4)-N(2)-Ni(l) 1 13.7(3)

C(2)-N(2)-Ni(l) 102.6(4)

C(2)#l-N(2)-Ni(l) 102.6(4)

C(7)-N(3)-C(8) 107.6(3)

C(7)-N(3)-C(5) 109.6(3)

C(8)-N(3)-C(5) 109.6(4)

C(7)-N(3)-Ni(2) 1 14.2(3)

C(8)-N(3)-Ni(2) 1 12.4(3)

C(5)-N(3)-Ni(2) 103.4(2)

C(6)-N(4)-C(9) 109.6(3)

C(6)-N(4)-C(10) 108.2(3)

C(9)-N(4)-C(10) 106.5(3)

C(6)-N(4)-Ni(2) 104.5(2)

C(9)-N(4)-Ni(2) 1 12.9(3) C(10)-N(4)-Ni(2) 1 15.0(3)

C(2)-C(l)-N(l) 107.4(6)

N(2)-C(2)-C(l) 109.2(6)

N(3)-C(5)-C(6) 1 10.9(3)

N(4)-C(6)-C(5) 109.5(4)

C1(5)#1-C(1 1)-C1(5) 1 15.2(4)

Symmetry transformations used to generate equivalent atoms:

#1 x,-y,z

Table 1-4. Anisotropic displacement parameters (A ² x 10 ³ ) for k09121. The anisotropic displacement factor exponent takes the form: -2π ² [ h ² a* ² U" + ... + 2 h k a* b* U ¹² ]

U" U ²² u ³³ u" u ¹³ u ¹²

Ni(l) 19(1) 21(1) 19(1) 0 8(1) 0

Ni(2) 18(1) 22(1) 21 (1) 1(1) 8(1) 1(1)

Cl(l) 20(1) 28(1 ) 29(1) 0 13(1) 0

Cl(2) 28(1) 22(1 ) 23(1) -1(1 ) 7(1) 0(1)

Cl(3) 21 (1) 29( 1) 27(1) 0 5(1) 0

Cl(4) 25(1) 40(1) 29(1) 0 12(1) 0

0(1) 15(2) 23(2) 19(2) 0 6(2) 0

N(l) 21(3) 37(3) 23(3) 0 8(2) 0

N(2) 26(3) 32(3) 20(3) 0 1 1(2) 0

N(3) 18(2) 29(2) 24(2) 1 (2) 9(2) 1 (2)

N(4) 22(2) 26(2) 32(2) 3(2) 12(2) 2(2)

C(l) 27(4) 37(6) 22(4) 6(3) 13(4) -3(3)

C(2) 16(4) 35(7) 22(4) -3(3) -2(3) -7(3)

C(3) 20(2) 27(3) 83(4) -7(3) 17(3) -7(2)

C(4) 94(5) 34(3) 39(3) -2(2) 46(3) -12(3)

C(5) 24(2) 30(2) 34(2) 13(2) 9(2) 5(2)

C(6) 30(2) 22(2) 42(3) 6(2) 18(2) 5(2)

C(7) 37(3) 35(3) 23(2) 5(2) 17(2) 2(2)

C(8) 26(2) 37(3) 35(3) 9(2) 13(2) -7(2)

C(9) 21(2) 33(3) 48(3) -2(2) 8(2) 3(2)

C(10) 43(3) 34(3) 39(3) 2(2) 25(2) 15(2)

Cl(5) 102(2) 80(1) 57( 1) 24( 1) -4(1) -50(1) U ¹¹ u ²² u ³³ u ²³ u ¹³ u ¹²

C(l lT 35(4) 43(4) 27(3) 0 13(3) 0

Table 1-5. Hydrogen coordinates ( x 10 ⁴ ) and isotropic displacement parameters (A ² x 10 ³ ) for k09121.

X y z U(eq)

H(10) 1990(50) 0 2760(50) 50(30)

H(1A) 3276 -1071 5645 33

H(1 B) 3994 -176 5982 33

H(2A) 2951 171 6536 33

H(2B) 2877 1055 5845 33

H(3A) 4210 893 4821 67

H(3B) 3352 1546 4647 67

H(3C) 3460 921 3882 67

H(4A) 1566 -873 6223 75

H(4B) 1780 -1541 5538 75

H(4C) 885 -936 5253 75

H(5A) -124 2568 901 36

H(5B) 568 3490 1 155 36

H(6A) 529 3594 2528 36

H(6B) -419 3759 1807 36

H(7A) 1296 2024 655 45

H(7B) 639 1 158 707 45

H(7C) 1647 1041 1270 45

H(8A) 2014 3139 1835 49

H(8B) 2356 2153 2448 49

H(8C) 1841 3053 2692 49

H(9A) - 1528 2632 1719 53

H(9B) -1327 1442 1997 53

H(9C) -1 1 15 1893 1225 53

H(10A) -748 3260 3076 54

H(10B) 217 2891 3622 54

H( 10C) -563 2094 3426 54

H(1 1A) -1 75 0 291 42 U(eq)

H(1 1B) -2656 -679 42

Table 1-6. Hydrogen bonds for k09121 [A and °].

D-H...A d(D-H) d(H...A) d(D...A) <(DHA)

0(1)-H(10)...C1(4) 0.85(8) 2.40(8) 3.237(4) 170(7)

Symmetry transformations used to generate equivalent atoms:

#1 x,-y,z

Treatment of alcoholic solutions of hydrated NiX ₂ (X = CI or Br) salts with bidentate nitrogen-donor ligand (L-K ² N,iV) lead to halide-bridged Ni clusters in the case where L is either the ligand N,N,A^,A etramethylethylenediamine (tmeda) or the organic azole 4,4-dimethyl-2-{2'-anilinyl}-2-oxazoline ("0XNH2") [U. Turpeinen, A. Pajunen, Finn. Chem. Lett., 1976, 6-11 ;] binding in a K ² jV,iV coordination motif. These clusters have the general formula [μ ₃ -(Χ)-μ ₃ -(ΟΗ)-{μ-(Χ) ₃ -(Νΐί) ₃ }]Χ (1: X = CI, L = tmeda [U. Turpeinen, A. Pajunen, Finn. Chem. Lett., 1976, 6-1 1]; 2: X = CI, L = oxNH ₂ and 3: X = Br, L = oxNH ₂ . In this case of clusters (2) and (3), both have been fully characterised (IR, μ _βίΐ , elemental analysis, single crystal X-ray diffraction).

Example 2 - Preparation of (rNirC _j ^MN^O^C OHIPre-catalyst cluster 2

Compound 2 was synthesised by the following method. A sample of NiCl ₂ ^» 6(H ₂ 0) (0.217 g: 0.913 mmol) and 0.52 g (2.7 mmol) of 4,4-dimethyl-2-(2'- anilinyl)-2-oxazoline (made according to K. M. Button & R. A. Gossage, J Heterocyclic Chem., 2003, 40, 513-517) were dissolved in 95% aq. EtOH (20 mL) and heated to reflux temperature in a 50 mL round-bottomed flask for a period of 4 h. The resulting green coloured solution was then evaporated to dryness (vacuo) and the residue washed with Et ₂ 0 (3 x 20 mL) to give the resulting green coloured product in a yield of 0.20 g (71%). Elemental analysis; calculated for C ₃₃ H ₄₃ N ₆ 0 ₄ Cl ₅ Ni3 (found): C 42.12 (41.88); H 4.61 (4.88); N 8.93 (9.09)%. The structural aspects of 2 were confirmed by the single crystal X-ray diffraction study (1070, below) of a sample of 2 that had been recrystallised from THF / hexanes mixtures.

Table 2-1. Crystal data and structure refinement for 1070.

Identification code 1070 (catalyst 2)

Empirical formula C33 H43 C15 N6 Ni3 04

Formula weight 941.05

Temperature 173(2)

Wavelength 0.71073 A

Crystal system Triclinic

Space group P -l

Unit cell dimensions a = 1 1.4038(4) A <x= 93.865(2)°.

b = 1 1.9005(4) A β= 104.381(2)°. c = 17.2457(6) A γ = 1 16.686(2)°.

Volume 1981.83(13) A ³

Z 2

Density (calculated) 1.577 Mg/m ³

Absorption coefficient 1.792 mm ^"1

F(000) 968

Crystal size 0.07 x 0.05 x 0.05 mm ³

Theta range for data collection 2.53 to 27.52°.

Index ranges -14<=h<=14, -15<=k<=15, -2 K=1<=22

Reflections collected 28922

Independent reflections 9086 [R(int) = 0.0934]

Completeness to theta = 27.52° 99.5 %

Absorption correction Psi-scan

Max. and min. transmission 0.914 and 0.861

Refinement method Full-matrix least-squares on F ²

Data / restraints / parameters 9086 / 0 / 478

Goodness-of-fit on F ² 1.024

Final R indices [I>2sigma(I)] Rl = 0.0510, wR2 = 0.0953

R indices (all data) Rl = 0.0885, wR2 = 0.1 108

Extinction coefficient 0.0036(4)

Largest diff. peak and hole 0.830 and -0.603 e.A" ³ Table 2-2. Atomic coordinates ( x 10 ⁴ ) and equivalent isotropic displacement parameters (A ² x 10 ³ ) for 1070. U(eq) is defined as one third of the trace of the orthogonalized U' ^J tensor.

X y z U(eq)

Cl(l) 303(1) 3921(1) 2987(1) 26(1)

Cl(2) 4550(1) 8001(1) 3622(1) 25(1)

Cl(3) 1375(1) 6415(1) 867(1) 24(1)

Cl(4) 1 143(1) 6976(1) 2759(1) 25(1)

Cl(5) 6207(2) 5788(2) 8239(5) 46(1)

Cl(6) 6279(6) 5695(7) 8717(14) 35(4)

0(4) 2475(3) 5650(2) 2357(2) 19(1)

Ni(l) 476(1 ) 4906(1) 1786(1) 19(1)

0(1) -3718(3) 2596(3) 458(2) 28(1)

N(l) 423(3) 3518(3) 969(2) 20(1)

N(2) -1584(3) 4138(3) 1202(2) 20(1)

C(l) -620(4) 2215(4) 853(2) 20(1)

C(2) -1986(4) 1949(4) 727(2) 21(1)

C(3) -301 1 (4) 659(4) 568(2) 26(1)

C(4) -2680(5) -323(4) 552(3) 29(1)

C(5) -1320(5) -46(4) 709(3) 33(1)

C(6) -297(5) 1224(4) 851 (3) 27(1)

C(7) -2360(4) 2971(4) 809(2) 22(1 )

C(8) -2484(4) 4733(4) 1235(2) 22(1)

C(9) -3863(5) 3745(4) 592(3) 32(1)

C(10) -1936(5) 6042(4) 1004(3) 33(1)

C(l l) -261 1(5) 4803(4) 2096(3) 29(1)

Ni(2) 2478(1 ) 5946(1) 3508(1) 20(1)

0(21) 2738(4) 5859(3) 5966(2) 41(1)

N(21) 3761 (4) 5158(3) 3893(2) 23(1)

N(22) 2506(3) 6251(3) 4695(2) 21(1)

C(21) 3364(4) 4220(4) 4384(3) 24(1)

C(22) 2904(4) 4439(4) 5032(3) 28(1)

C(23) 2553(5) 3506(5) 5516(3) 38(1)

C(24) 2629(5) 2390(5) 5346(3) 45(1)

C(25) 3042(5) 2179(5) 4695(3) 44(1)

C(26) 3415(5) 3084(4) 4219(3) 36(1)

C(27) 2724(5) 5566(4) 5193(2) 29(1)

C(28) 2221(5) 7192(4) 5128(3) 30(1) X y z U(eq)

C(29) 2513(5) 6960(5) 6006(3) 40(1)

C(30) 710(5) 6848(5) 4763(3) 44(1)

C(31) 3180(6) 8563(5) 5088(3) 49(2)

Ni(3) 3175(1) 7447(1) 2206(1) 19(1)

0(41) 5599(3) 1 1250(3) 2056(2) 28(1)

N(41) 4626(3) 7393(3) 1697(2) 24(1)

N(42) 3936(3) 9297(3) 2065(2) 20(1)

C(41) 6029(4) 8378(4) 2107(2) 23(1)

C(42) 6306(4) 9660(4) 2264(2) 23(1)

C(43) 7687(5) 10618(4) 2623(3) 31(1)

C(44) 8734(5) 10319(5) 2840(3) 41(1)

C(45) 8431(5) 9031(5) 2704(3) 41(1)

C(46) 7083(5) 8071(4) 2337(3) 34(1)

C(47) 5202(4) 10012(4) 21 10(2) 22(1)

C(48) 3280(4) 10134(4) 2046(3) 25(1)

C(49) 4331(5) 11330(4) 1824(3) 32(1)

C(50) 3179(5) 10430(4) 2894(3) 35(1)

C(51) 1862(5) 9505(4) 1408(3) 40(1)

Table2-3. Bond lengths [A] and angles [°] for 1070.

Cl(l)-Ni(2) 2.4493(11) C(8)-C(l l) 1.527(5) C(30)-H(30A) 0.9800

Cl(l)-Ni(l) 2.4550(11) C(8)-C(9) 1.543(6) C(30)-H(30B) 0.9800

Cl(2)-Ni(3) 2.4094(11) C(9)-H(9A) 0.9900 C(30)-H(30C) 0.9800

Cl(2)-Ni(2) 2.4739(11) C(9)-H(9B) 0.9900 C(31)-H(31A) 0.9800

Cl(3)-Ni(3) 2.4612(11) C(10)-H(10A) 0.9800 C(31)-H(31B) 0.9800

Cl(3)-Ni(l) 2.5153(11) C(10)-H(10B) 0.9800 C(31)-H(31C) 0.9800

Cl(4)-Ni(2) 2.5302(12) C(10)-H(10C) 0.9800 Ni(3)-N(42) 2.030(3)

Cl(4)-Ni(l) 2.5666(11) C(11)-H(11A) 0.9800 Ni(3)-N(41) 2.079(3)

Cl(4)-Ni(3) 2.5676(11) C(11)-H(11B) 0.9800 0(41)-C(47) 1.351(5)

C1(5)-C1(6) 0.826(17) C(11)-H(11C) 0.9800 0(41)-C(49) 1.449(5)

0(4)-Ni(l) 1.976(3) Ni(2)-N(22) 2.044(3) N(41)-C(41) 1.441(5)

0(4)-Ni(3) 1.980(3) Ni(2)-N(21) 2.072(3) N(41)-H(41A) 0.9200

0(4)-Ni(2) 1.991(3) 0(21)-C(27) 1.349(5) N(41)-H(41B) 0.9200

0(4)-H(4A) 1.0000 0(21)-C(29) 1.445(6) N(42)-C(47) 1.284(5)

Ni(l)-N(2) 2.035(3) N(21)-C(21) 1.426(5) N(42)-C(48) 1.489(5)

Ni(l)-N(l) 2.067(3) N(21)-H(21A) 0.9200 C(41)-C(46) 1.383(6)

0(1)-C(7) 1.357(5) N(21)-H(21B) 0.9200 C(41)-C(42) 1.403(5)

0(1)-C(9) 1.459(5) N(22)-C(27) 1.280(5) C(42)-C(43) 1.404(6)

N(l)-C(l) 1.429(5) N(22)-C(28) 1.501(5) C(42)-C(47) 1.467(6)

N(1)-H(1A) 0.9200 C(21)-C(26) 1.392(6) C(43)-C(44) 1.368(7)

N(1)-H(1B) 0.9200 C(21)-C(22) 1.402(6) C(43)-H(43) 0.9500

N(2)-C(7) 1.282(5) C(22)-C(23) 1.407(6) C(44)-C(45) 1.400(7)

N(2)-C(8) 1.494(5) C(22)-C(27) 1.464(6) C(44)-H(44) 0.9500

C(l)-C(6) 1.385(6) C(23)-C(24) 1.385(7) C(45)-C(46) 1.383(7)

C(l)-C(2) 1.398(6) C(23)-H(23) 0.9500 C(45)-H(45) 0.9500

C(2)-C(3) 1.404(5) C(24)-C(25) 1.371(8) C(46)-H(46) 0.9500

C(2)-C(7) 1.468(6) C(24)-H(24) 0.9500 C(48)-C(51) 1.518(6)

C(3)-C(4) 1.381(6) C(25)-C(26) 1.377(7) C(48)-C(50) 1.525(6)

C(3)-H(3) 0.9500 C(25)-H(25) 0.9500 C(48)-C(49) 1.543(6)

C(4)-C(5) 1.380(6) C(26)-H(26) 0.9500 C(49)-H(49A) 0.9900

C(4)-H(4) 0.9500 C(28)-C(31) 1.520(6) C(49)-H(49B) 0.9900

C(5)-C(6) 1.389(6) C(28)-C(30) 1.526(7) C(50)-H(50A) 0.9800

C(5)-H(5) 0.9500 C(28)-C(29) 1.539(6) C(50)-H(50B) 0.9800

C(6)-H(6) 0.9500 C(29)-H(29A) 0.9900 C(50)-H(50C) 0.9800

C(8)-C(10) 1.520(6) C(29)-H(29B) 0.9900 C(51)-H(51A) 0.9800 C(51)-H(51B) 0.9800 C(51)-H(51C) 0.9800

Ni(2)-Cl(l)-Ni(l) 76.22(3) C(7)-N(2)-Ni(l) 123.7(3) C(8)-C(10)-H(10A) 109.5

Ni(3)-Cl(2)-Ni(2) 75.85(3) C(8)-N(2)-Ni(l) 127.7(2) C(8)-C(10)-H(10B) 109.5

Ni(3)-Cl(3)-Ni(l) 75.94(3) C(6)-C(l)-C(2) 120.1(4) H(10A)-C(10)-H(10B) 109.5

Ni(2)-Cl(4)-Ni(l) 72.86(3) C(6)-C(l)-N(l) 121.0(4) C(8)-C(10)-H(10C) 109.5

Ni(2)-Cl(4)-Ni(3) 72.15(3) C(2)-C(l)-N(l) 1 18.9(4) H(10A)-C(10)-H(10C) 109.5

Ni(l)-Cl(4)-Ni(3) 73.23(3) C(l)-C(2)-C(3) 1 18.3(4) H(10B)-C(10)-H(10C) 109.5

Ni(l)-0(4)-Ni(3) 101.46(12) C(l)-C(2)-C(7) 122.1(4) C(8)-C(11)-H(11A) 109.5

Ni(l)-0(4)-Ni(2) 99.46(12) C(3)-C(2)-C(7) 1 19.5(4) C(8)-C(11)-H(11B) 109.5

Ni(3)-0(4)-Ni(2) 98.22(11) C(4)-C(3)-C(2) 121.0(4) H(11A)-C(11)-H(11B) 109.5

Ni(l)-0(4)-H(4A) 1 18.0 C(4)-C(3)-H(3) 1 19.5 C(8)-C(1 1)-H(11C) 109.5

Ni(3)-0(4)-H(4A) 118.0 C(2)-C(3)-H(3) 1 19.5 H(11A)-C(11)-H(11C) 109.5

Ni(2)-0(4)-H(4A) 118.0 C(5)-C(4)-C(3) 120.2(4) H(11B)-C(11)-H(11C) 109.5

0(4)-Ni(l)-N(2) 179.76(12) C(5)-C(4)-H(4) 119.9 0(4)-Ni(2)-N(22) 179.23(13)

0(4)-Ni(l)-N(l) 93.74(12) C(3)-C(4)-H(4) 1 19.9 0(4)-Ni(2)-N(21) 92.09(12)

N(2)-Ni(l)-N(l) 86.39(13) C(4)-C(5)-C(6) 1 19.5(4) N(22)-Ni(2)-N(21) 87.23(13)

0(4)-Ni(l)-Cl(l) 82.17(8) C(4)-C(5)-H(5) 120.2 0(4)-Ni(2)-Cl(l) 82.01(8)

N(2)-Ni(l)-Cl(l) 97.60(9) C(6)-C(5)-H(5) 120.2 N(22)-Ni(2)-Cl(l) 98.43(10)

N(l)-Ni(l)-Cl(l) 102.09(9) C(l)-C(6)-C(5) 120.8(4) N(21)-Ni(2)-Cl(l) 97.24(10)

0(4)-Ni(l)-Cl(3) 81.41(8) C(l)-C(6)-H(6) 1 19.6 0(4)-Ni(2)-Cl(2) 82.81(8)

N(2)-Ni(l)-Cl(3) 98.80(9) C(5)-C(6)-H(6) 1 19.6 N(22)-Ni(2)-Cl(2) 96.80(10)

N(l)-Ni(l)-Cl(3) 86.24(9) N(2)-C(7)-0(l) 116.9(4) N(21)-Ni(2)-Cl(2) 88.58(10)

Cl(l)-Ni(l)-Cl(3) 162.03(4) N(2)-C(7)-C(2) 128.2(4) Cl(l)-Ni(2)-Cl(2) 163.92(4)

0(4)-Ni(l)-Cl(4) 74.63(8) 0(1)-C(7)-C(2) 1 14.8(3) 0(4)-Ni(2)-Cl(4) 75.25(8)

N(2)-Ni(l)-Cl(4) 105.28(10) N(2)-C(8)-C(10) 112.2(3) N(22)-Ni(2)-Cl(4) 105.39(10)

N(l)-Ni(l)-Cl(4) 165.50(9) N(2)-C(8)-C(l l) 107.5(3) N(21)-Ni(2)-Cl(4) 166.41(9)

C1(l)-Ni(l)-Cl(4) 85.14(4) C(10)-C(8)-C(l l) 112.1(4) Cl(l )-Ni(2)-Cl(4) 86.05(4)

Cl(3)-Ni(l)-Cl(4) 83.51(3) N(2)-C(8)-C(9) 101.8(3) Cl(2)-Ni(2)-Cl(4) 84.98(4)

C(7)-0(l)-C(9) 106.1(3) C(10)-C(8)-C(9) 1 1 1.0(4) C(27)-0(21)-C(29) 106.2(4)

C(l)-N(l)-Ni(l) 1 18.4(2) C(l l)-C(8)-C(9) 1 11.7(3) C(21)-N(21)-Ni(2) 1 17.4(3)

C(1)-N(1)-H(1A) 107.7 0(1)-C(9)-C(8) 104.4(3) C(21)-N(21)-H(21A) 107.9

Ni(l)-N(l)-H(1A) 107.7 0(1)-C(9)-H(9A) 110.9 Ni(2)-N(21)-H(21A) 107.9

C(1)-N(1)-H(1B) 107.7 C(8)-C(9)-H(9A) 110.9 C(21)-N(21)-H(21B) 107.9

Ni(l)-N(l)-H(1B) 107.7 0(1)-C(9)-H(9B) 1 10.9 Ni(2)-N(21)-H(21B) 107.9

H(1A)-N(1)-H(1B) 107.1 C(8)-C(9)-H(9B) 1 10.9 H(21A)-N(21)-H(21B) 107.2

C(7)-N(2)-C(8) 108.1(3) H(9A)-C(9)-H(9B) 108.9 C(27)-N(22)-C(28) 108.1(3) C(27) -N(22) -Ni(2) 122.4(3) H(30A)-C(30)-H(30B) 109.5 C(42) -C(41) -N(41) 1 18.5(4)

C(28) -N(22) -Ni(2) 129.4(3) C(28)-C(30)-H(30C) 109.5 C(41) -C(42) -C(43) 118.0(4)

C(26) -C(21) -C(22) 119.9(4) H(30A)-C(30)-H(30C) 109.5 C(41) -C(42) -C(47) 122.2(4)

C(26) -C(21) -N(21) 120.5(4) H(30B)-C(30)-H(30C) 109.5 C(43) -C(42) -C(47) 1 19.7(4)

C(22) -C(21) -N(21) 119.6(4) C(28)-C(31)-H(31A) 109.5 C(44) -C(43) -C(42) 121.5(4)

C(21) -C(22) -C(23) 118.0(4) C(28)-C(31)-H(31B) 109.5 C(44) -C(43) -H(43) 1 19.2

C(21) -C(22) -C(27) 122.3(4) H(31A)-C(31)-H(31 B) 109.5 C(42) -C(43) -H(43) 1 19.2

C(23) -C(22) -C(27) 119.6(4) C(28)-C(31)-H(31C) 109.5 C(43) -C(44) -C(45) 1 19.6(4)

C(24) -C(23) -C(22) 121.1(5) H(31A)-C(31)-H(31C) 109.5 C(43) -C(44) -H(44) 120.2

C(24) -C(23) -H(23) 119.5 H(31B)-C(31)-H(31C) 109.5 C(45) -C(44) -H(44) 120.2

C(22) -C(23) -H(23) 119.5 0(4)-Ni(3)-N(42) 178.74(13) C(46) -C(45) -C(44) 120.0(5)

C(25) -C(24) -C(23) 119.9(5) 0(4)-Ni(3)-N(41) 93.53(12) C(46) -C(45) -H(45) 120.0

C(25) -C(24) -H(24) 120.1 N(42)-Ni(3)-N(41) 85.71(13) C(44) -C(45) -H(45) 120.0

C(23) -C(24) -H(24) 120.1 0(4)-Ni(3)-Cl(2) 84.76(8) C(45) -C(46) -C(41) 120.2(4)

C(24) -C(25) -C(26) 120.4(5) N(42)-Ni(3)-Cl(2) 94.34(10) C(45) -C(46) -H(46) 119.9

C(24) -C(25) -H(25) 119.8 N(41)-Ni(3)-Cl(2) 97.44(10) C(41) -C(46) -H(46) 1 19.9

C(26) -C(25) -H(25) 119.8 0(4)-Ni(3)-Cl(3) 82.75(8) N(42; -C(47 -0(41) 1 17.2(4)

C(25) -C(26) -C(21) 120.7(5) N(42)-Ni(3)-Cl(3) 98.24(10) N(42; -C(47^ -C(42) 127.2(4)

C(25) -C(26) -H(26) 119.6 N(41)-Ni(3)-Cl(3) 90.17(10) o(4 i; -C(47) -C(42) 1 15.4(3)

C(21) -C(26) -H(26) 119.6 Cl(2)-Ni(3)-Cl(3) 165.75(4) N(42; -C(48 -C(51) 1 11.4(3)

N(22; -C(27 -0(21) 117.6(4) 0(4)-Ni(3)-Cl(4) 74.55(8) N(42; -C(48; -C(50) 108.8(3)

N(22; -C(27 -C(22) 128.5(4) N(42)-Ni(3)-Cl(4) 106.28(10) C(51) -C(48) -C(50) 1 10.6(4)

0(2 r -C(27 -C(22) 113.9(4) N(41)-Ni(3)-Cl(4) 167.47(9) N(42] -C(48 -C(49) 101.1(3)

N(22; -C(28, -C(31) 111.1(4) Cl(2)-Ni(3)-Cl(4) 85.50(4) C(51) -C(48) -C(49) 1 12.2(4)

N(22; -C(28; -C(30) 109.8(4) Cl(3)-Ni(3)-Cl(4) 84.57(4) C(50) -C(48) -C(49) 1 12.3(4)

C(31) -C(28) -C(30) 111.2(4) C(47)-0(41)-C(49) 105.2(3) 0( 1; -C(49^ -C(48) 104.2(3)

N(22; -C(28; -C(29) 101.7(4) C(41)-N(41)-Ni(3) 1 14.8(2) o(4i; -C(49^ -H(49A) 1 10.9

C(31) -C(28) -C(29) 111.9(4) C(41)-N(41)-H(41A) 108.6 C(48) -C(49) -H(49A) 1 10.9

C(30) -C(28) -C(29) 110.8(4) Ni(3)-N(41)-H(41A) 108.6 0(41; -C(49) -H(49B) 1 10.9

0(21; -C(29; -C(28) 105.9(3) C(41)-N(41)-H(41B) 108.6 C(48) -C(49) -H(49B) 110.9

0(2 I; -C(29] -H(29A) 110.6 Ni(3)-N(41)-H(41 B) 108.6 H(49A)-C(49)-H(49B) 108.9

C(28) -C(29) -H(29A) 110.6 H(41A)-N(41)-H(41 B) 107.6 C(48) -C(50) -H(50A) 109.5

0(2 I ; -C(29) -H(29B) 110.6 C(47)-N(42)-C(48) 107.4(3) C(48) -C(50) -H(50B) 109.5

C(28) -C(29) -H(29B) 110.6 C(47)-N(42)-Ni(3) 123.1(3) H(50A)-C(50)-H(50B) 109.5

H(29A)-C(29)-H(29B) 108.7 C(48)-N(42)-Ni(3) 128.7(3) C(48)-C(50)-H(50C) 109.5

C(28) -C(30) -H(30A) 109.5 C(46)-C(41)-C(42) 120.6(4) H(50A)-C(50)-H(50C) 109.5

C(28) -C(30) -H(30B) 109.5 C(46)-C(41)-N(41) 120.9(4) H(50B)-C(50)-H(50C) 109.5 C(48)-C(51)-H(51A) 109.5 H(51A)-C(51)-H(51B) 109.5 H(51A)-C(51)-H(51C) 109.5

C(48)-C(51)-H(51B) 109.5 C(48)-C(51)-H(51C) 109.5 H(51B)-C(51)-H(51C) 109.5

Table 2-4. Anisotropic displacement parameters (A½ 10 ³ ) for 1070. The anisotropic

displacement factor exponent takes the form: -2π ² [ h ² a* ² U ⁿ + ... + 2 h k a* b* U ¹² ]

U ¹¹ U" u ³³ U ²³ U ¹³ U ¹²

Cl(l) 22(1) 23(1) 24(1) 7(1) 7(1) 4(1)

Cl(2) 21(1 ) 22(1) 22(1) 3(1) 3(1) 5(1)

Cl(3) 25(1) 20(1) 20(1) 4(1) 4(1) 7(1)

Cl(4) 23(1) 24(1) 25(1) 3(1) 6(1) 1 1(1)

Cl(5) 29(1) 34(1) 76(4) -2(1) 15(1) 20(1)

Cl(6) 18(3) 29(3) 53(9) -8(4) 4(3) 12(2)

0(4) 20(1) 15(1) 18(1) 4(1) 5(1) 5(1)

Ni(l) 16(1) 17(1) 19(1) 2(1) 4(1) 6(1)

O(l) 13(1) 28(2) 35(2) 0(1) 2(1) 7(1)

N(l) 13(2) 20(2) 22(2) 3(1) 4(1) 5(1)

N(2) 19(2) 23(2) 20(2) 5(D 7(1) 10(1)

C(l) 17(2) 20(2) 20(2) 2(2) 4(2) 7(2)

C(2) 19(2) 19(2) 21(2) -1(2) 4(2) 6(2)

C(3) 20(2) 21(2) 24(2) 0(2) 4(2) 2(2)

C(4) 32(3) 19(2) 27(2) 1(2) 6(2) 7(2)

C(5) 37(3) 22(2) 36(3) 10(2) 6(2) 14(2)

C(6) 24(2) 26(2) 32(2) 7(2) 4(2) 14(2)

C(7) 12(2) 27(2) 21(2) 5(2) 4(2) 6(2)

C(8) 17(2) 28(2) 25(2) 5(2) 7(2) 14(2)

C(9) 25(2) 38(3) 36(3) 2(2) 6(2) 21(2)

C(10) 31(3) 36(3) 40(3) 10(2) 1 1(2) 23(2)

C(l l) 31(2) 32(2) 26(2) 1 (2) 13(2) 16(2)

Ni(2) 19(1) 19(1) 18(1) 3(1) 5(1) 7(1)

0(21) 51(2) 62(2) 20(2) 1 1(2) 16(2) 34(2)

N(21) 24(2) 24(2) 19(2) 1(1) 6(1) 1 1(2)

N(22) 18(2) 23(2) 19(2) 0(1) 5(1) 9(1)

C(21) 19(2) 24(2) 28(2) 8(2) 2(2) 10(2)

C(22) 22(2) 34(2) 27(2) 13(2) 7(2) 14(2)

C(23) 30(3) 51(3) 42(3) 28(2) 16(2) 22(2)

C(24) 36(3) 47(3) 59(3) 36(3) 13(3) 22(2) U ¹¹ u ²² u ³³ u ²³ u ¹³ u ¹²

C(25) 37(3) 30(3) 62(4) 12(2) 6(3) 19(2)

C(26) 36(3) 31(2) 37(3) 6(2) 5(2) 16(2)

C(27) 26(2) 37(2) 18(2) 3(2) 6(2) 12(2)

C(28) 29(2) 32(2) 27(2) -4(2) 12(2) 13(2)

C(29) 36(3) 49(3) 25(2) -7(2) 1 1(2) 14(2)

C(30) 43(3) 59(3) 40(3) 5(3) 17(2) 33(3)

C(31) 59(4) 31(3) 51(3) -5(2) 27(3) 12(3)

Ni(3) 19(1) 16(1) 21(1) 4(1) 6(1) 6(1)

0(41) 31(2) 16(1) 38(2) 7(1) 12(1) 10(1)

N(41) 26(2) 17(2) 26(2) 1(1) 12(2) 7(2)

N(42) 24(2) 17(2) 20(2) 5(D 6(1) 10(1)

C(41 ) 21 (2) 20(2) 26(2) 4(2) 13(2) 6(2)

C(42) 26(2) 20(2) 22(2) 5(2) 12(2) 8(2)

C(43) 26(2) 25(2) 36(3) 4(2) 16(2) 5(2)

C(44) 23(3) 37(3) 52(3) 3(2) 14(2) 6(2)

C(45) 27(3) 43(3) 53(3) 1 1(2) 15(2) 16(2)

C(46) 35(3) 29(2) 44(3) 1 1(2) 20(2) 17(2)

C(47) 29(2) 15(2) 19(2) 2(2) 9(2) 7(2)

C(48) 28(2) 21 (2) 28(2) 6(2) 9(2) 14(2)

C(49) 36(3) 18(2) 44(3) 12(2) 12(2) 14(2)

C(50) 36(3) 27(2) 39(3) -1(2) 12(2) 16(2)

C(51) 34(3) 26(2) 52(3) 5(2) -1(2) 16(2)

Table 2-5. Hydrogen coordinates ( x 10 ⁴ ) and isotropic displacement parameters (A½ 10 ³ ) for 1070.

X y z U(eq)

H(4A) 2955 5174 2221 23

H(1A) 331 3749 468 24

H(1B) 1268 3543 1136 24

H(3) -3948 458 470 31

H(4) -3389 -1191 433 35

H(5) -1087 -718 720 39

H(6) 637 1414 948 32

H(9A) -4650 3567 800 38

H(9B) -4007 4061 79 38

H(10A) -1041 6640 1407 50

H(10B) -2590 6367 996 50

H(10C) -1824 5962 461 50

H(1 1A) -2926 3949 2230 43

H(1 1B) -3278 5099 2120 43

H(1 1C) -1708 5406 2491 43

H(21A) 3840 4790 3436 27

H(21B) 4625 5819 4183 27

H(23) 2259 3644 5965 45

H(24) 2394 1772 5681 54

H(25) 3072 1404 4571 52

H(26) 3710 2931 3772 43

H(29A) 3342 7722 6381 47

H(29B) 1717 6785 6205 47

H(30A) 534 6955 4195 65

H(30B) 507 7414 5081 65

H(30C) 116 5952 4780 65

H(31A) 4142 8743 5297 74

H(31B) 3040 9163 5423 74

H(31C) 2978 8668 4520 74

H(41A) 4585 6603 1699 29

H(41B) 4388 7466 1 160 29

H(43) 7898 11494 2716 37

H(44) 9662 10982 3081 49

H(45) 9152 8817 2865 49 x y z U(eq)

H(46) 6880 7198 2242 41

H(49A) 4027 11309 1230 39

H(49B) 4455 12129 2131 39

H(50A) 2677 9623 3063 52

H(50B) 2685 10926 2878 52

H(50C) 41 10 10930 3286 52

H(51A) 1924 9200 885 60

H(5 IB) 1529 10132 1340 60

H(51 C) 1219 8776 1585 60

Table 2-6. Torsion angles [°] for 1070.

Ni(3)-0(4)-Ni()>N(l) 121.02(13) Ni(2)-Cl(4)-Ni(l)-N(l) -76.2(4)

Ήί(2)-0(4)--Νϊ(1)-Ν(1) -138.52(12) Ni(3)-Cl(4)-Ni(l)-N(l) -0.2(4)

Ni(3)-0(4)-Mi(l)-Cl(l) -137.27(10) Ni(2)-Cl(4)-Ni(l)-Cl(l) 44.53(3)

Ni(2)-0(4)-Ni(l)-Cl(l) -36.81(8) Ni(3)-Cl(4)-Ni(l)-Cl(l) 120.52(4)

Ni(3)-0(4)-Ni( l)-Cl(3) 35.39(9) Ni(2)-CI(4)-Ni(l )-Cl(3) -121.51(4)

Ni(2)-0(4)-Ni( l)-Cl(3) 135.85(10) Ni(3)-Cl(4)-Ni(l)-Cl(3) -45.53(3)

Ni(3)-0(4)-Ni(l)-Cl(4) -50.19(8) 0(4)-Ni(l)-N(l)-C(l) 130.7(3)

Ni(2)-0(4)-Ni(l)-Cl(4) 50.27(8) N(2)-Ni(l)-N(l)-C(l) -49.1(3)

Ni(2)-CI(l)-Ni(l)-0(4) 29.65(8) Cl(l)-Ni(l)-N(l)-C(l) 47.9(3)

Ni(2)-Cl(l)-Ni(l)-N(2) -150.26(10) Cl(3)-Ni(l)-N(l)-C(l) -148.2(3)

Ni(2)-Cl(l)-Ni(l)-N(l) 121.82(9) Cl(4)-Ni(l)-N(l)-C(I) 166.7(3)

Ni(2)-Cl(l)-Ni(l)-Cl(3) 5.49(14) N(l)-Ni(l)-N(2)-C(7) 25.2(3)

Ni(2)-Cl(l)-Ni(l)-Cl(4) -45.46(3) Cl(l)-Ni(l)-N(2)-C(7) -76.5(3)

Ni(3)-Cl(3)-Ni(l)-0(4) -28.07(8) Cl(3)-Ni(l)-N(2)-C(7) 110.9(3)

Ni(3)-Cl(3)-Ni(l )-N(2) 151.81(10) Cl(4)-Ni(l)-N(2)-C(7) -163.5(3)

Ni(3)-Cl(3)-Ni(l)-N(l) -122 43(9) N(l)-Ni(l)-N(2)-C(8) -163.2(3)

Ni(3)-Cl(3)-Ni(l)-Cl(l) -3.87(14) Cl(l)-Ni(l)-N(2)-C(8) 95.0(3)

Ni(3)-Cl(3)-Ni(l>Cl(4) 47.29(3) Cl(3)-Ni(l)-N(2)-C(8) -77.6(3)

Ni(2)-Cl(4)-Ni( l)-0(4) -38.67(8) Cl(4)-Ni(l)-N(2)-C(8) 8.0(3)

Ni(3)-Cl(4)-Ni(l)-0(4) 37.32(8) Ni(l)-N(l)-C(l)-C(6) -133.6(3)

Ni(2)-Cl(4)-Ni(l)-N(2) 141.10(10) Ni(l)-N(l)-C(l)-C(2) 47.3(5)

Ni(3)-Cl(4)--Ni(l)-N(2) -142.92(10) C(6)-C(l)-C(2)-C(3) -2.5(6) N(l)-C(l)-C(2)-C(3) 176.5(3) Ni(3)-0(4)-Ni(2)-Cl(4) 52.09(9)

C(6)-C(l)-C(2)-C(7) 173.4(4) Ni(l)-Cl(l)-Ni(2)-0(4) -29.41(8)

N(l)-C(l)-C(2)-C(7) -7.5(6) Ni(l)-Cl(l)-Ni(2)-N(22) 151.23(10)

C(l)-C(2)-C(3)-C(4) 1.3(6) Ni(l)-Cl(l)-Ni(2)-N(21) -120.52(9)

C(7)-C(2)-C(3)-C(4) -174.7(4) Ni(l)-Cl(l)-Ni(2)-Cl(2) -9.97(16)

C(2)-C(3)-C(4)-C(5) 1.2(6) Ni(l)-CI(l)-Ni(2)-Cl(4) 46.23(3)

C(3)-C(4)-C(5)-C(6) -2.5(7) Ni(3)-Cl(2)-Ni(2)-0(4) 28.43(8)

C(2)-C(l)-C(6)-C(5) 1.3(6) Ni(3)-Cl(2)-Ni(2)-N(22) -152.25(10)

N(l)-C(l)-C(6)-C(5) -177.8(4) Ni(3)-Cl(2)-Ni(2)-N(21 ) 120.72(9)

C(4)-C(5)-C(6)-C(l) 1.3(7) Ni(3)-Cl(2)-Ni(2)-Cl(l) 9.03(16)

C(8)-N(2)-C(7)-0(l) 6.5(5) Ni(3)-Cl(2)-Ni(2)-Cl(4) -47.30(3)

Ni(l)-N(2)-C(7)-0(1) 179.4(2) Ni(l)-Cl(4)-Ni(2)-0(4) 38.18(8)

C(8)-N(2)-C(7)-C(2) -169.6(4) Ni(3)-Cl(4)-Ni(2)-0(4) -39.24(8)

Ni(l)-N(2)-C(7)-C(2) 3.3(6) Ni(l)-Cl(4)-Ni(2)-N(22) -142.26(10)

C(9)-0(l)-C(7)-N(2) 4.6(5) Ni(3)-Cl(4)-Ni(2)-N(22) 140.33(10)

C(9)-0(l)-C(7)-C(2) -178.8(3) Ni(l)-Cl(4)-Ni(2)-N(21) 60.0(4)

C(l)-C(2)-C(7)-N(2) -21.2(7) Ni(3)-Cl(4)-Ni(2)-N(21) -17.4(4)

C(3)-C(2)-C(7)-N(2) 154.7(4) Ni(l)-Cl(4)-Ni(2)-Cl(l) -44.59(3)

C(l)-C(2)-C(7)-0(1) 162.7(4) Ni(3)-Cl(4)-Ni(2)-Cl(l) -122.01(3)

C(3)-C(2)-C(7)-0(l) -21.5(5) Ni(l)-Cl(4)-Ni(2)-Cl(2) 122.05(3)

C(7)-N(2)-C(8)-C(10) -132.5(4) Ni(3)-Cl(4)-Ni(2)-Cl(2) 44.64(3)

Ni(l)-N(2)-C(8)-C(10) 54.9(4) 0(4)-Ni(2)-N(21)-C(21) -131.3(3)

C(7)-N(2)-C(8)-C(l l) 103.8(4) N(22)-Ni(2)-N(21)-C(21) 49.0(3)

Ni(l)-N(2)-C(8)-C(l l) -68.8(4) Cl(l)-Ni(2)-N(21)-C(21) -49.1(3)

C(7)-N(2)-C(8)-C(9) -13.7(4) Cl(2)-Ni(2)-N(21)-C(21) 145.9(3)

Ni(l)-N(2)-C(8)-C(9) 173.6(3) Cl(4)-Ni(2)-N(21)-C(21) -152.4(3)

C(7)-0(l)-C(9)-C(8) -12.9(4) N(21)-Ni(2)-N(22)-C(27) -26.1(3)

N(2)-C(8)-C(9)-0(l) 15.8(4) Cl(l)-Ni(2)-N(22)-C(27) 70.8(3)

C(10)-C(8)-C(9)-O(l) 135.4(4) Cl(2)-Ni(2)-N(22)-C(27) -114.3(3)

C(l l)-C(8)-C(9)-0(1) -98.7(4) Cl(4)-Ni(2)-N(22)-C(27) 159.0(3)

Ni(l)-0(4)-Ni(2)-N(21) 133.95(13) N(21 )-Ni(2)-N(22)-C(28) 157.6(3)

Ni(3)-0(4)-Ni(2)-N(21) -122.90(13) Cl(l)-Ni(2)-N(22)-C(28) -105.5(3)

Ni(l)-0(4)-Ni(2)-Cl(l) 36.93(8) Cl(2)-Ni(2)-N(22)-C(28) 69.4(3)

Ni(3)-0(4)-Ni(2)-Cl(l) 140.08( 10) Cl(4)-Ni(2)-N(22)-C(28) -17.3(3)

Ni(l)-0(4)-Ni(2)-Cl(2) -137.74(10) Ni(2)-N(21)-C(21)-C(26) 134.2(4)

Ni(3)-0(4)-Ni(2)-Cl(2) -34.59(9) Ni(2)-N(21 )-C(21)-C(22) -45.1(5)

Ni(l)-0(4)-Ni(2)-Cl(4) -51.07(8) C(26)-C(21)-C(22)-C(23) 2.2(6) N(21)-C(21)-C(22)-C(23) -178.5(4) Ni(2)-0(4)-lMi(3)-Cl(4) -51.27(8)

C(26)-C(21)-C(22)-C(27) -175.0(4) Ni(2)-Cl(2)-Ni(3)-0(4) -28.50(8)

N(21)-C(21)-C(22)-C(27) 4.3(6) Ni(2)-Cl(2)-Ni(3)-N(42) 152.38(10)

C(21)-C(22)-C(23)-C(24) -1.4(7) Ni(2)-Cl(2)-Ni(3)-N(4l) -121.39(9)

C(27)-C(22)-C(23)-C(24) 175.9(5) Ni(2)-Cl(2)-Ni(3)-Cl(3) 0.39(18)

C(22)-C(23)-C(24)-C(25) -0.5(8) Ni(2)-Cl(2)-Ni(3)-Cl(4) 46.36(3)

C(23)-C(24)-C(25)-C(26) 1.5(8) Ni(l)-Cl(3)-Ni(3)-0(4) 27.92(8)

C(24)-C(25)-C(26)-C(21) -0.7(8) Ni(l)-Cl(3)-Ni(3)-N(42) -152.85(10)

C(22)-C(21 )-C(26)-C(25) -1.2(7) Ni(l)-Cl(3)-Ni(3)-N(41) 121.46(10)

N(21)-C(21)-C(26)-C(25) 179.5(4) Ni(l)-Cl(3)-Ni(3)-Cl(2) -1.09(18)

C(28)-N(22)-C(27)-0(21) -3.8(5) Ni(l)-CI(3)-Ni(3)-Cl(4) -47.15(3)

Ni(2)-N(22)-C(27)-0(21) 179.2(3) Ni(2)-Cl(4)-Ni(3)-0(4) 39.67(8)

C(28)-N(22)-C(27)-C(22) 173.1(4) Ni(l)-Cl(4)-Ni(3)-0(4) -37.25(8)

Ni(2)-N(22)-C(27)-C(22) -3.9(6) Ni(2)-Cl(4)-Ni(3)-N(42) -139.34(10)

C(29)-0(21)-C(27)-N(22) -1.2(5) Ni(l)-Cl(4)-Ni(3)-N(42) 143.74(10)

C(29)-0(21)-C(27)-C(22) -178.6(4) Ni(2)-Cl(4)-Ni(3)-N(41) 58.0(5)

C(21)-C(22)-C(27)-N(22) 24.3(7) Ni(l)-Cl(4)-Ni(3)-N(41) -18.9(5)

C(23)-C(22)-C(27)-N(22) -152.9(5) Ni(2)-Cl(4)-Ni(3)-Cl(2) -46.12(3)

C(21)-C(22)-C(27)-0(21) -158.8(4) Ni(l)-Cl(4)-Ni(3)-Cl(2) -123.05(3)

C(23)-C(22)-C(27)-0(21) 24.1(6) Ni(2)-Cl(4)-Ni(3)-Cl(3) 123.63(3)

C(27)-N(22)-C(28)-C(31) 125.8(4) Ni(l)-Cl(4)-Ni(3)-Cl(3) 46.71(3)

Ni(2)-N(22)-C(28)-C(31) -57.4(5) 0(4)-Ni(3)-N(41)-C(41) -124.2(3)

C(27)-N(22)-C(28)-C(30) -110.8(4) N(42)-Ni(3)-N(41>C(41) 54.8(3)

Ni(2)-N(22)-C(28)-C(30) 66.0(5) Cl(2)-Ni(3)-N(41)-C(41) -39.0(3)

C(27)-N(22)-C(28)-C(29) 6.6(4) Cl(3)-Ni(3)-N(41)-C(41) 153.1(3)

Ni(2)-N(22)-C(28)-C(29) -176.6(3) Cl(4)-Ni(3)-N(41 )-C(41) -141.9(4)

C(27)-0(21 )-C(29)-C(28) 5.5(5) N(41)-Ni(3)-N(42)-C(47) -31.5(3)

N(22)-C(28)-C(29)-0(21) -7.2(4) Cl(2)-Ni(3)-N(42)-C(47) 65.6(3)

C(31)-C(28)-C(29)-0(21) -125.8(4) Cl(3)-Ni(3)-N(42)-C(47) -121.1 (3)

C(30)-C(28)-C(29)-O(21) 109.5(4) Cl(4)-Ni(3)-N(42)-C(47) 152.2(3)

Ni(l)-0(4)-Ni(3)-N(41) -125.88(13) N(41 )-Ni(3)-N(42)-C(48) 160.4(3)

Ni(2)-0(4)-Ni(3)-N(41) 132.66(13) Cl(2)-Ni(3)-N(42)-C(48) -102.5(3)

Ni(l)-0(4)-Ni(3)-Cl(2) 136.96(10) Cl(3)-Ni(3)-N(42)-C(48) 70.8(3)

Ni(2)-0(4)-Ni(3)-Cl(2) 35.50(9) Cl(4)-Ni(3)-N(42)-C(48) -15.9(3)

Ni(l)-0(4)-Ni(3)-Cl(3) -36.15(9) Ni(3)-N(41 )-C(41)-C(46) 129.7(4)

Ni(2)-0(4)-Ni(3)-Cl(3) -137.62(10) Ni(3)-N(41)-C(41)-C(42) -50.8(4)

Ni(l)-0(4)-Ni(3)-Cl(4) 50.19(8) C(46)-C(41)-C(42)-C(43) 3.1(6) N(41 )-C(41 )-C(42)-C(43) - 176.4(3)

C(46)-C(41 )-C(42)-C(47) - 173.4(4)

N(41)-C(41)-C(42)-C(47) 7.1(6)

C(41)-C(42)-C(43)-C(44) -2.2(6)

C(47)-C(42)-C(43)-C(44) 174.4(4)

C(42)-C(43)-C(44)-C(45) 0.0(7)

C(43)-C(44)-C(45)-C(46) 1.4(8)

C(44)-C(45)-C(46)-C(41) -0.5(7)

C(42)-C(41)-C(46)-C(45) -1.8(7)

N(41)-C(41)-C(46)-C(45) 177.7(4)

C(48)-N(42)-C(47)-0(41 ) -5.7(5)

Ni(3)-N(42)-C(47)-0(41 ) - 176.0(2)

C(48)-N(42)-C(47)-C(42) 170.3(4)

Ni(3)-N(42)-C(47)-C(42) 0.0(6)

C(49)-0(41)-C(47)-N(42) -9.1(5)

C(49)-0(41)-C(47)-C(42) 174.4(3)

C(41)-C(42)-C(47)-N(42) 22.6(6)

C(43)-C(42)-C(47)-N(42) -153.8(4)

C(41 )-C(42)-C(47)-0(41 ) -161.3(4)

C(43)-C(42)-C(47)-0(41) 22.3(5)

C(47)-N(42)-C(48)-C(51) 136.1(4)

Ni(3)-N(42)-C(48)-C(51) -54.3(5)

C(47)-N(42)-C(48)-C(50) - 101.6(4)

Ni(3)-N(42)-C(48)-C(50) 67.9(4)

C(47)-N(42)-C(48)-C(49) 16.7(4)

Ni(3)-N(42)-C(48)-C(49) -173.7(3)

C(47)-0(41)-C(49)-C(48) 18.9(4)

N(42)-C(48)-C(49)-0(41) -21.3(4)

C(51 )-C(48)-C(49)-0(41 ) - 140.1 (4)

C(50)-C(48)-C(49)-O(41) 94.5(4) Table 2-7. Hydrogen bonds for 1070 [A and °].

D-H...A d(D-H) d(H...A) d(D...A) <(DHA)

0(4)-H(4A)...Cl(5)#l 1.00 2.02 3.015(4) 170.9

0(4)-H(4A)...Cl(6)# l 1.00 2.40 3.31 1(13) 151.9

N(1)-H(1A)...C1(3)#2 0.92 2.55 3.345(3) 145.2

N(1)-H(1B)...C1(6)#1 0.92 2.46 3.327(7) 157.2

N(1)-H(1B)...C1(5)#1 0.92 2.52 3.421 (4) 165.0

N(21)-H(21A)...C1(5)#1 0.92 2.91 3.786(8) 160.8

N(41)-H(41A)...C1(6)#1 0.92 2.43 3.309(8) 158.7

N(41)-H(41A)...C1(5)#1 0.92 2.59 3.482(4) 163.6

Symmetry transformations used to generate equivalent atoms:

# 1 -x+ 1 ,-y+ 1 ,-z+ 1 #2 -x,-y+ 1 ,-z

Figure 1-A is an ORTEP diagram of the cationic component of 2. Example 3 - Preparation of Pre-Catalyst Cluster 3

Compound 3 was synthesised by the following method. A sample of ΝΪΒΓ ₂ ·3(Η20) (0.29 g: 1.1 mmol) and 0.41 g (2.2 mmol) of 4,4-dimethyl-2-(2'-anilinyl)-2-oxazoline (made according to: K. M. Button & R. A. Gossage, J. Heterocyclic Chem., 2003, 40, 513-517) were dissolved in 95% aq. EtOH (20 mL) and heated to reflux temperature in a 50 mL round-bottomed flask for a period of 12 h. The resulting green coloured solution was then evaporated to dryness {vacuo) and the residue washed with Et ₂ 0 (3 x 20 mL) and hexanes (10 mL) to give the resulting green coloured product in a yield of 0.31 g (69%). Elemental analysis; calculated for C3 ₃ H ₄ 3N ₆ 0 ₄ Br ₅ Ni3'(hexane)o _. 75 (found): C 36.68 (36.85); H 4.39 (4.57); N 7.22 (7.24)%. The structural aspects of 3 were confirmed by the single crystal X-ray diffraction study (1092, below) of a sample of 3 that had been recrystallised from THF / hexanes mixtures.

Table 3-1. Crystal data and structure refinement for 1092 (Pre-Catalyst 3).

Identification code 1092

Empirical formula C33 H43 Br5 N6 Ni3 04

Formula weight 1 163.41

Temperature 173(2) K

Wavelength 0.71073 A

Crystal system Triclinic

Space group P -l

Unit cell dimensions a = 1 1.648(2) A oc= 73.57(3)°.

b = 1 1.780(2) A β= 71.43(3)°. c = 17.747(4) A γ = 64.57(3)°.

Volume 2054.1 (9) A ³

Z 2

Density (calculated) 1.881 Mg/m ³

Absorption coefficient 6.267 mm ^-1

F(000) 1 148

Crystal size 0.05 x 0.02 x 0.02 mm ³

Theta range for data collection 3.26 to 23.26°.

Index ranges -12<=h<=12, -13<=k<=l 1 , -19<=1<=18 Reflections collected 12086

Independent reflections 5713 [R(int) = 0.1 145]

Completeness to theta = 23.26° 97.0 %

Absorption correction Psi-scan

Max. and min. transmission 0.882 and 0.759

Refinement method Full-matrix least-squares on F ²

Data / restraints / parameters 5713 / 36 / 467

Goodness-of-fit on F ² 1.061

Final R indices [I>2sigma(I)] Rl = 0.0718, wR2 = 0.1283

R indices (all data) Rl = 0.131 l , wR2 = 0.1503

Extinction coefficient 0.0019(3)

Largest diff. peak and hole 0.718 and -0.844 e.A" ³ Table 3-2. Atomic coordinates ( x 10 ⁴ ) and equivalent isotropic displacement parameters (A ² x 10 ³ ) for 1092. U(eq) is defined as one third of the trace of the orthogonalized U'J tensor.

X y z U(eq)

Br(l) 2873(1) 4032(1) 1951(1) 30(1)

Br(2) -820(1) 8256(1) 1267(1) 30(1)

Br(3) -471(1) 6541(1) 4193(1) 32(1)

Br(4) 1718(1) 7291(2) 2307(1) 36(1)

Br(5) 821 1(1) 4312(2) 2962(1) 38(1)

Ni(l) 1450(2) 5093(2) 3190(1) 23(1)

Ni(2) 11 10(2) 6110(2) 1425(1) 24(1)

Ni(3) -874(2) 7651(2) 2766(1) 23(1)

0(1) 4120(10) 2808(10) 4648(6) 43(3)

0(4) 77(8) 5880(8) 2556(5) 17(2)

0(21) 3223(10) 5576(1 1) -924(6) 45(3)

0(41) -3578(9) 1 1352(9) 2989(6) 30(2)

N(l) 832(10) 3619(9) 3815(6) 20(3)

N(2) 2806(10) 4326(11) 3880(6) 26(3)

N(21) 182(10) 5290(11) 1028(6) 22(3)

N(22) 2181(10) 6242(11) 268(6) 26(3)

N(41) -2708(9) 7509(10) 3140(6) 22(3)

N(42) -1872(10) 9476(11) 2991(6) 28(3)

C(l) 1795(14) 2322(14) 3899(7) 28(4)

C(2) 2910(13) 21 15(13) 4140(8) 29(4)

C(3) 3768(13) 875(15) 4302(8) 34(4)

C(4) 3567(15) -130(16) 4184(8) 35(4)

C(5) 2482(13) 85(14) 3905(8) 30(3)

C(6) 1632(14) 1342(15) 3752(8) 35(4)

C(7) 3217(12) 3162(13) 4216(7) 23(3)

C(8) 3597(15) 4928(15) 4001(9) 38(4)

C(9) 4258(16) 3937(16) 4679(11) 55(5)

C(10) 2763(18) 6226(16) 4281(1 1) 57(5)

C(l l) 4600(15) 5031(17) 3208(10) 55(5)

C(21) 1031(13) 4223(14) 635(7) 24(3)

C(22) 21 10(14) 4305(14) 19(8) 30(4)

C(23) 2895(13) 3248(17) -365(9) 39(4)

C(24) 2643(16) 2153(17) -135(10) 46(5)

C(25) 1637(16) 2042(17) 476(10) 46(5) X y z U(eq)

C(26) 788(15) 3103(15) 873(8) 39(4)

C(27) 2457(13) 5391(14) -169(7) 27(4)

C(28) 2906(13) 7100(15) -189(8) 36(4)

C(29) 3407(15) 6752(16) -1018(9) 42(4)

C(30) 4014(14) 6831(17) 217(9) 46(5)

C(31) 2007(16) 8484(16) -226(1 1) 58(5)

C(41) -3679(12) 8450(13) 2700(8) 25(3)

C(42) -3861(13) 9715(13) 2620(8) 26(3)

C(43) -4829(14) 10647(16) 2230(9) 39(4)

C(44) -5545(16) 10298(16) 1915(9) 44(5)

C(45) -5323(13) 9024(16) 2007(9) 41(4)

C(46) -4378(12) 8100(15) 2392(9) 32(4)

C(47) -3045(13) 10124(13) 2870(8) 24(3)

C(48) -1425(14) 10362(13) 3174(8) 30(4)

C(49) -2714(14) 11479(15) 3371(10) 39(4)

C(50) -496(13) 10716(15) 2405(8) 35(4)

C(51) -775(14) 9743(14) 3875(8) 34(4)

Table 3-3. Bond lengths [A] and angles [°] for 1092.

Br(l)-Ni(l) 2.569(2) 0(21)-C(29) 1.45(2) C(8)-C(9) 1.559(19)

Br(l)-Ni(2) 2.587(2) 0(41)-C(47) 1.357(16) C(21)-C(26) 1.39(2)

Br(2)-Ni(3) 2.539(2) 0(41)-C(49) 1.454(18) C(21)-C(22) 1.398(19)

Br(2)-Ni(2) 2.576(2) N(l)-C(l) 1.456(16) C(22)-C(23) 1.40(2)

Br(3)-Ni(3) 2.588(2) N(2)-C(7) 1.273(17) C(22)-C(27) 1.42(2)

Br(3)-Ni(l) 2.643(2) N(2)-C(8) 1.47(2) C(23)-C(24) 1.37(2)

Br(4)-Ni(l) 2.710(3) N(21)-C(21) 1.426(17) C(24)-C(25) 1.34(2)

Br(4)-Ni(3) 2.737(2) N(22)-C(27) 1.309(19) C(25)-C(26) 1.42(2)

Br(4)-Ni(2) 2.770(3) N(22)-C(28) 1.492(1 ) C(28)-C(29) 1.50(2)

Ni(l)-0(4) 1.991(8) N(41)-C(41) 1.454(15) C(28)-C(31) 1.51(2)

Ni(l)-N(2) 2.046(10) N(42)-C(47) 1.301(16) C(28)-C(30) 1.55(2)

Ni(l)-N(l) 2.059(11) N(42)-C(48) 1.494(19) C(41)-C(46) 1.35(2)

Ni(2)-0(4) 1.996(8) C(l)-C(6) 1.35(2) C(41)-C(42) 1.38(2)

Ni(2)-N(22) 2.037(11) C(l)-C(2) 1.40(2) C(42)-C(43) 1.400(18)

Ni(2)-N(21) 2.089(12) C(2)-C(3) 1.381(19) C(42)-C(47) 1.46(2)

Ni(3)-0(4) 1.978(8) C(2)-C(7) 1.47(2) C(43)-C(44) 1.38(2)

Ni(3)-N(42) 2.044(12) C(3)-C(4) 1.38(2) C(44)-C(45) 1.38(2)

Ni(3)-N(41) 2.091(11) C(4)-C(5) 1.40(2) C(45)-C(46) 1.376(19)

0(1)-C(7) 1.350(16) C(5)-C(6) 1.390(19) C(48)-C( 1) 1.505(19)

0(1)-C(9) 1.42(2) C(8)-C(ll) 1.53(2) C(48)-C(50) 1.527(19)

0(21)-C(27) 1.370(16) C(8)-C(10) 1.54(2) C(48)-C(49) 1.529(19)

Ni(l)-Br(l)-Ni(2) 74.19(7) N(l)-Ni(l)-Br(3) 87.6(3) N(22)-Ni(2)-Br(l) 94.6(3)

Ni(3)-Br(2)-Ni(2) 74.74(7) Br(l)-Ni(l)-Br(3) 163.87(8) N(21)-Ni(2)-Br(l) 98.3(3)

Ni(3)-Br(3)-Ni(l) 74.29(7) 0(4)-Ni(l)-Br(4) 74.3(3) Br(2)-Ni(2)-Br(l) 165.78(8)

Ni(l)-Br(4)-Ni(3) 70.89(7) N(2)-Ni(l)-Br(4) 105.7(3) 0(4)-Ni(2)-Br(4) 72.8(3)

Ni(l)-Br(4)-Ni(2) 69.14(7) N(l)-Ni(l)-Br(4) 167.2(3) N(22)-Ni(2)-Br(4) 109.7(4)

Ni(3)-Br(4)-Ni(2) 68.64(7) Br(l)-Ni(l)-Br(4) 87.49(7) N(21)-Ni(2)-Br(4) 163.7(3)

0(4)-Ni(l)-N(2) 177.6(4) Br(3)-Ni(l)-Br(4) 85.94(8) Br(2)-Ni(2)-Br(4) 84.07(7)

0(4)-Ni(l)-N(l) 93.7(4) 0(4)-Ni(2)-N(22) 176.7(5) Br(l)-Ni(2)-Br(4) 85.89(7)

N(2)-Ni(l)-N(l) 86.1(4) 0(4)-Ni(2)-N(21) 92.0(4) 0(4)-Ni(3)-N(42) 179.5(4)

0(4)-Ni(l)-Br(l) 84.0(2) N(22)-Ni(2)-N(21) 85.7(5) 0(4)-Ni(3)-N(41) 94.4(4)

N(2)-Ni(l)-Br(l) 98.4(3) 0(4)-Ni(2)-Br(2) 84.0(2) N(42)-Ni(3)-N(41) 85.1(4)

N(l)-Ni(l)-Br(l) 95.8(3) N(22)-Ni(2)-Br(2) 98.3(3) 0(4)-Ni(3)-Br(2) 85.4(2)

0(4)-Ni(l)-Br(3) 80.0(2) N(21)-Ni(2)-Br(2) 88.8(3) N(42)-Ni(3)-Br(2) 94.9(3)

N(2)-Ni(l)-Br(3) 97.6(3) 0(4)-Ni(2)-Br(l) 83.4(2) N(41)-Ni(3)-Br(2) 96.4(3) 0(4)-Ni(3)-Br(3) 81.7(2) N(2)-C(7)-C(2) 127.9(12) C(41)-C(46)-C(45) 119.4(15)

N(42)-Ni(3)-Br(3) 98.1(3) 0(1)-C(7)-C(2) 115.1( 12) N(42)-C(47)-0(41) 115.7(13)

N(41)-Ni(3)-Br(3) 89.3(3) N(2)-C(8)-C(ll) 106.9( 13) N(42)-C(47)-C(42) 128.9(13)

Br(2)-Ni(3)-Br(3) 166.22(8) N(2)-C(8)-C(10) 112.7( 13) 0(41)-C(47)-C(42) 115.5(11)

0(4)-Ni(3)-Br(4) 73.8(3) C(ll)-C(8)-C(10) 112.5( 15) N(42)-C(48)-C(51) 110.8(11)

N(42)-Ni(3)-Br(4) 106.7(3) N(2)-C(8)-C(9) 102.3( 12) N(42)-C(48)-C(50) 106.7(11)

N(41)-Ni(3)-Br(4) 167.9(3) C(ll) -C(8)-C(9) 111.5( 13) C(51)-C(48)-C(50) 112.0(12)

Br(2)-Ni(3)-Br(4) 85.44(7) C(10) -C(8)-C(9) 110.4( 14) N(42)-C(48)-C(49) 101.4(12)

Br(3)-Ni(3)-Br(4) 86.48(7) 0(1)- C(9)-C(8) 102.8( 13) C(51)-C(48)-C(49) 112.6(12)

C(7)-0(l)-C(9) 107.2(11) C(26) -C(21)-C(22) 120.4( 13) C(50)-C(48)-C(49) 112.8(12)

Ni(3)-0(4)-Ni(l) 105.5(4) C(26) -C(21)-N(21) 119.8( 12) 0(41)-C(49)-C(48) 104.3(12)

Ni(3)-0(4)-Ni(2) 102.8(4) C(22) -C(21)-N(21) 119.9( 13)

Ni(l)-0(4)-Ni(2) 102.5(4) C(23) -C(22)-C(21) 117.9( 15)

C(27)-0(21)-C(29) 107.4(12) C(23) -C(22)-C(27) 121.0( 14)

C(47)-0(41)-C(49) 105.9(10) C(21 -C(22)-C(27) 120.9( 13)

C(l)-N(l)-Ni(l) 119.0(9) C(24) -C(23)-C(22) 121.5( 15)

C(7)-N(2)-C(8) 107.2(11) C(25) -C(24)-C(23) 121.3( 15)

C(7)-N(2)-Ni(l) 124.4(10) C(24) -C(25)-C(26) 119.4( 17)

C(8)-N(2)-Ni(l) 128.0(9) C(21} -C(26)-C(25) 119.5 ;i5)

C(21)-N(21)-Ni(2) 115.3(8) N(22 )-C(27)-0(21) 113.91 :i )

C(27)-N(22)-C(28) 108.5(11) N(22 )-C(27)-C(22) 130.61 ;i3)

C(27)-N(22)-Ni(2) 120.5(10) 0(21 )-C(27)-C(22) 115.5 ;i3)

C(28)-N(22)-Ni(2) 130.5(10) N(22 )-C(28)-C(29) 102.9 :i )

C(41)-N(41)-Ni(3) 115.6(8) N(22 )-C(28)-C(31) 111.21 ;ii)

C(47)-N(42)-C(48) 107.9(12) C(29; -C(28)-C(31) 110.1 ;i3)

C(47)-N(42)-Ni(3) 120.8(11) N(22 )-C(28)-C(30) 109.5

C(48)-N(42)-Ni(3) 130.6(8) C(29 -C(28)-C(30) 112.9 ;i2)

C(6)-C(l)-C(2) 120.4(13) c(3i; -C(28)-C(30) 110.0 116)

C(6)-C(l)-N(l) 121.9(13) 0(21 )-C(29)-C(28) 105.4 ;i2)

C(2)-C(l)-N(l) 117.7(14) C(46 -C(41)-C(42) 121.9 ;i3)

C(3)-C(2)-C(l) 118.3(15) C(46} -C(41)-N(41) 121.3 ;i3)

C(3)-C(2)-C(7) 118.8(13) C(42 -C(41)-N(41) 116.8 ;i )

C(l)-C(2)-C(7) 122.8(12) C(41] -C(42)-C(43) 118.U ;i5)

C(2)-C(3)-C(4) 120.8(14) C(41 -C(42)-C(47) 123.6 ;i2)

C(3)-C(4)-C(5) 120.8(15) C(43) -C(42)-C(47) 118.1 :i3)

C(6)-C(5)-C(4) 117.1(15) C(44) -C(43)-C(42) 120.3 ,16)

C(l)-C(6)-C(5) 122.2(14) C(43) -C(44)-C(45) 119.41 Ί4)

N(2)-C(7)-0(l) 116.9(14) C(46J -C(45)-C(44) 120.9( 17) Table 3-4. Anisotropic displacement parameters (A ² x 10 ³ )for 1092. The anisotropic displacement factor exponent takes the form: -2π ² [ h ² a* ² U" + ... + 2 h k a* b* U ¹² ]

U ¹¹ u" u ³³ u ²³ u ¹³ U ¹²

Br(l) 23(1) 26(1) 27(1) -2(1) -5(1) 2(1)

Br(2) 29(1) 24(1) 29(1) 0(1) -9(1) -4(1)

Br(3) 35(1) 28(1) 25(1) -3(1) -7(1) -5(1)

Br(4) 31(1) 33(1) 43(1) 1(1) -13(1) -14(1)

Br(5) 30(1) 28(1) 59(1 ) -5(1) -14(1) -13(1)

Ni(l) 20(1) 22(1) 23(1) 2(1) -7(1) -7(1)

Ni(2) 20(1) 23(1) 22(1) 0(1) -5(1 ) -5(1)

Ni(3) 21(1) 17(1) 26(1) -1(1) -6(1) -4(1)

0(1) 43(6) 44(7) 48(6) 10(5) -36(5) -14(6)

0(4) 14(4) 1 1(5) 28(5) -5(4) -5(4) -6(4)

0(21) 35(6) 57(8) 26(6) -2(5) 3(5) -12(6)

0(41) 22(5) 21(6) 43(6) -9(4) 1(4) -7(4)

N(l) 20(6) 12(6) 21(6) 2(5) -8(5) 0(5)

N(2) 25(6) 31(7) 23(6) 4(5) -9(5) -16(6)

N(21) 16(6) 31(7) 9(5) -5(5) 1(4) -2(5)

N(22) 19(6) 24(7) 24(6) 4(5) -8(5) 1(5)

N(41) 19(5) 10(5) 36(5) -4(4) -8(4) -3(4)

N(42) 9(6) 32(7) 25(6) -3(5) 2(5) 2(5)

C(l ) 36(9) 27(9) 19(7) -2(6) -10(6) -8(7)

C(2) 27(8) 18(8) 37(8) -9(6) -1(7) -9(7)

C(3) 21(8) 35(10) 31(8) 6(7) -7(6) -3(7)

C(4) 45(10) 42(10) 23(8) -4(7) -5(7) -24(8)

C(5) 36(5) 23(5) 29(5) -10(4) -1 (4) -10(4)

C(6) 32(9) 42(10) 28(8) -3(7) -10(7) -1 1(8)

C(7) 15(5) 26(5) 22(5) 5(4) -3(4) -8(4)

C(8) 38(9) 32(10) 49(10) -1(8) -22(8) -1 1(8)

C(9) 46(10) 32(1 1) 93(14) 22(9) -52(10) -15(9)

C(10) 67(1 1) 37(10) 90(12) -9(9) -45(9) -23(8)

C(l l) 41(10) 48(12) 79(13) 22(10) -36(10) -23(9)

C(21) 30(8) 33(9) 13(7) -2(6) -7(6) -15(7)

C(22) 36(9) 32(9) 25(8) -7(7) -10(7) -1 1(7)

C(23) 17(8) 56(12) 37(9) -27(8) -4(7) 4(8)

C(24) 37(10) 40(1 1) 61(1 1) -25(9) -19(9) 3(9) U ¹¹ U22 u ³³ U ²³ u ¹³ U ¹²

C(25) 44(10) 47(1 1) 67(12) -23(9) -23(10) -19(9)

C(26) 43(10) 45(1 1) 24(8) -7(7) 0(7) -18(9)

C(27) 30(8) 32(9) 18(7) 0(7) -11(6) -9(7)

C(28) 22(8) 36(10) 35(9) 2(7) 2(7) -9(7)

C(29) 35(9) 41(1 1) 44(9) 10(8) -16(8) -13(8)

C(30) 37(9) 60(12) 47(10) -14(9) 0(8) -27(9)

C(31) 47(9) 42(10) 63(10) 14(8) 9(8) -25(8)

C(41) 20(7) 18(8) 24(7) 2(6) 6(6) -4(6)

C(42) 30(8) 14(8) 34(8) -7(6) -7(6) -6(6)

C(43) 36(9) 36(10) 40(9) 2(7) -10(8) -13(8)

C(44) 53(11) 35(11) 36(9) 3(7) -24(8) -6(9)

C(45) 18(8) 44(1 1) 52(10) -15(8) -8(7) 2(8)

C(46) 17(7) 28(9) 53(9) -16(7) -7(7) -6(7)

C(47) 34(7) 13(6) 24(6) 2(5) -4(5) -13(5)

C(48) 48(9) 18(8) 33(8) -12(6) -12(7) -14(7)

C(49) 34(9) 27(9) 55(10) -15(8) -3(8) -10(7)

C(50) 27(8) 35(9) 43(9) 0(7) -8(7) -17(7)

C(51) 46(9) 22(8) 41(9) -14(7) -3(7) -19(7)

Hydrogen coordinates ( x 10 ⁴ ) and isotropic displacement parameters (A ² x 10 ³ )

X y z U(eq)

H(4A) -487 5386 2652 21

H(1A) 388 3793 4326 24

H(1B) 238 3633 3570 24

H(21A) -390 5036 1465 26

H(21B) -301 5905 677 26

H(41A) -2604 6709 3094 26

H(41B) -3027 7577 3677 26

H(3) 4505 71 1 4497 41

H(4) 4172 -976 4294 42

H(5) 2334 -600 3823 36

H(6) 912 1519 3537 42

H(9A) 5190 3812 4567 66

H(9B) 3807 4205 5212 66

H(10A) 2300 6819 3866 85

H(10B) 3331 6571 4369 85

H(10C) 2129 61 12 4785 85

H(1 1A) 5135 4178 3071 83

H(1 1B) 5160 541 1 3267 83

H(1 1C) 4146 5569 2777 83

H(23) 3619 3293 -795 47

H(24) 3191 1455 -412 55

H(25) 1493 1264 641 56

H(26) 62 3044 1297 46

H(29A) 2909 7430 -1400 51

H(29B) 4342 6627 -1221 51

H(30A) 3655 6872 793 69

H(30B) 441 1 7472 -36 69

H(30C) 4678 5980 150 69

H(31A) 1276 8633 -450 87

H(31 B) 2489 9023 -572 87

H(31C) 1672 8696 318 87

H(43) -4993 1 1524 2182 47

H(44) -6185 10929 1637 53

H(45) -5829 8782 1802 49 X y z U(eq)

H(46) -4219 7223 2442 38

H(49A) -3065 11422 3961 47

H(49B) -2598 12304 3147 47

H(50A) 186 9937 2219 52

H(50B) -94 11213 2516 52

H(50C) -985 11226 1986 52

H(51A) -1326 9360 4318 51

H(51B) -651 10386 4056 51

H(51C) 75 9078 3707 51

Table 3-6. Torsion angles [°] for 1092.

Ni(2)-Br(l)-Ni(l)-0(4) 25.8(3)

Ni(2)-Br(l)-Ni(l)-N(2) -154.2(3)

Ni(2)-Br(l)-Ni(l)-N(l) 118.9(3)

Ni(2)-Br(l)-Ni(l)-Br(3) 17.4(4)

Ni(2)-Br(l)-Ni(l)-Br(4) -48.66(7)

Ni(3)-Br(3)-Ni(l)-0(4) -27.2(3)

Ni(3)-Br(3)-Ni(l)-N(2) 152.9(3)

Ni(3)-Br(3)-Ni(l)-N(l) -121.3(3)

Ni(3)-Br(3)-Ni(l)-Br(l) -18.7(4)

Ni(3)-Br(3)-Ni(l)-Br(4) 47.57(7)

Ni(3)-Br(4)-Ni(l)-0(4) 35.5(2)

Ni(2)-Br(4)-Ni(l)-0(4) -38.3(2)

Nt(3)-Br(4)-Ni(l)-N(2) -142.1(3)

Ni(2)-Br(4)-Ni(l)-N(2) 144.2(3)

Ni(3)-Br(4)-Ni(l)-N(l) 14.8(14)

Ni(2)-Br(4)-Ni(l)-N(l) -58.9(14)

Ni(3)-Br(4)-Ni(l)-Br(l) 119.94(8)

Ni(2)-Br(4)-Ni(l)-Br(l) 46.23(6)

Ni(3)-Br(4)-Ni(l)-Br(3) -45.32(6)

Ni(2)-Br(4)-Ni(l)-Br(3) -119.03(7)

Ni(3)-Br(2)-Ni(2)-0(4) 23.5(3)

Ni(3)-Br(2)-Ni(2)-N(22) -158.8(4) Ni(3)-Br(2)-Ni(2)-N(21) 1 15.7(3)

Ni(3)-Br(2)-Ni(2)-Br(l) -4.4(4)

Ni(3)-Br(2)-Ni(2)-Br(4) -49.71(7)

Ni(l)-Br(l)-Ni(2)-0(4) -25.7(3)

Ni(l)-Br(l)-Ni(2)-N(22) 156.8(4)

Ni(l)-Br(l)-Ni(2)-N(21) -1 16.8(3)

Ni(l)-Br(l)-Ni(2)-Br(2) 2.3(4)

Ni(l)-Br(l)-Ni(2)-Br(4) 47.38(7)

Ni(l)-Br(4)-Ni(2)-0(4) 38.5(2)

Ni(3)-Br(4)-Ni(2)-0(4) -38.4(2)

Ni(l)-Br(4)-Ni(2)-N(22) -139.3(3)

Ni(3)-Br(4)-Ni(2)-N(22) 143.8(3)

Ni(l)-Br(4)-Ni(2)-N(21) 59.7(10)

Ni(3)-Br(4)-Ni(2)-N(21) -17.2(10)

Ni(l)-Br(4)-Ni(2)-Br(2) 124.01(7)

Ni(3)-Br(4)-Ni(2)-Br(2) 47.14(6)

Ni(l )-Br(4)-Ni(2)-Br(l) -45.91 (6)

Ni(3)-Br(4)-Ni(2)-Br(l) -122.78(8)

Ni(2)-Br(2)-Ni(3)-0(4) -23.7(3)

Ni(2)-Br(2)-Ni(3)-N(42) 156.8(3)

Ni(2)-Br(2)-Ni(3)-N(41) - 1 17.7(3)

Ni(2)-Br(2)-Ni(3)-Br(3) -3.9(4)

Ni(2)-Br(2)-Ni(3)-Br(4) 50.37(7)

Ni(l)-Br(3)-Ni(3)-0(4) 27.2(3)

Ni(l)-Br(3)-Ni(3)-N(42) -153.3(3)

Ni(l)-Br(3)-Ni(3)-N(41) 121.8(3)

Ni(l)-Br(3)-Ni(3)-Br(2) 7.2(4)

Ni(l)-Br(3)-Ni(3)-Br(4) -46.92(7)

Ni(l)-Br(4)-Ni(3)-0(4) -35.8(2)

Ni(2)-Br(4)-Ni(3)-0(4) 38.6(2)

Ni(l)-Br(4)-Ni(3)-N(42) 143.9(3)

Ni(2)-Br(4)-Ni(3)-N(42) -141.7(3)

Ni(l)-Br(4)-Ni(3)-N(41) -22.9(14)

Ni(2)-Br(4)-Ni(3)-N(41) 51.5(14)

Ni(l)-Br(4)-Ni(3)-Br(2) -122.30(8)

Ni(2)-Br(4)-Ni(3)-Br(2) -47.91 (6) Ni(l)-Br(4)-Ni(3)-Br(3) 46.53(7)

Ni(2)-Br(4)-Ni(3)-Br(3) 120.92(7)

N(41)-Ni(3)-0(4)-Ni(l) -126.0(4)

Br(2)-Ni(3)-0(4)-Ni(l) 138.0(3)

Br(3)-Ni(3)-0(4)-Ni(l) -37.4(3)

Br(4)-Ni(3)-0(4)-Ni(l) 51.4(3)

N(41)-Ni(3)-0(4)-Ni(2) 127.0(4)

Br(2)-Ni(3)-0(4)-Ni(2) 30.9(3)

Br(3)-Ni(3)-0(4)-Ni(2) -144.4(3)

Br(4)-Ni(3)-0(4)-Ni(2) -55.7(3)

N(l)-Ni(l)-0(4)-Ni(3) 123.6(4)

Br(l)-Ni(l)-0(4)-Ni(3) -141.0(3)

Br(3)-Ni(l)-0(4)-Ni(3) 36.6(3)

Br(4)-Ni(l)-0(4)-Ni(3) -51.9(3)

N(l)-Ni(l)-0(4)-Ni(2) -129.2(4)

Br(l)-Ni(l)-0(4)-Ni(2) -33.8(3)

Br(3)-Ni(l)-0(4)-Ni(2) 143.9(4)

Br(4)-Ni(l)-0(4)-Ni(2) 55.3(3)

N(21)-Ni(2)-0(4)-Ni(3) -1 19.0(4)

Br(2)-Ni(2)-0(4)-Ni(3) -30.5(3)

Br(l)-Ni(2)-0(4)-Ni(3) 142.9(3)

Br(4)-Ni(2)-0(4)-Ni(3) 55.1(3)

N(21)-Ni(2)-0(4)-Ni(l) 131.6(4)

Br(2)-Ni(2)-0(4)-Ni(l) -139.8(3)

Br(l)-Ni(2)-0(4)-Ni(l) 33.5(3)

Br(4)-Ni(2)-0(4)-Ni(l) -54.2(3)

0(4)-Ni(l)-N(l)-C(l) 133.6(9)

N(2)-Ni(l)-N(l)-C(l) -48.8(9)

Br(l)-Ni(l)-N(l)-C(l) 49.2(9)

Br(3)-Ni(l)-N(l)-C(l) -146.6(9)

Br(4)-Ni(l)-N(l)-C(l) 153.5(10)

N(l)-Ni(l)-N(2)-C(7) 23.9(1 1)

Br(l)-Ni(l)-N(2)-C(7) -71.4(10)

Br(3)-Ni(l)-N(2)-C(7) 1 1 1.0(10)

Br(4)-Ni(l)-N(2)-C(7) -161.1(10)

N(l)-Ni(l)-N(2)-C(8) -164.4(12) Br(l)-Ni(l)-N(2)-C(8) 100.4(1 1)

Br(3)-Ni(l)-N(2)-C(8) -77.3(1 1)

Br(4)-Ni(l)-N(2)-C(8) 10.6(12)

0(4)-Ni(2)-N(21)-C(21) -123.8(8)

N(22)-Ni(2)-N(21)-C(21) 53.8(8)

Br(2)-Ni(2)-N(21)-C(21) 152.2(8)

Br(l)-Ni(2)-N(21)-C(21) -40.2(8)

Br(4)-Ni(2)-N(21)-C(21) -144.1 (8)

N(21)-Ni(2)-N(22)-C(27) -31.6(10)

Br(2)-Ni(2)-N(22)-C(27) - 1 19.7(9)

Br(l)-Ni(2)-N(22)-C(27) 66.4(10)

Br(4)-Ni(2)-N(22)-C(27) 153.7(9)

N(21)-Ni(2)-N(22)-C(28) 157.2(1 1)

Br(2)-Ni(2)-N(22)-C(28) 69.1(10)

Br(l)-Ni(2)-N(22)-C(28) -104.8(10)

Br(4)-Ni(2)-N(22)-C(28) -17.5(1 1)

0(4)-Ni(3)-N(41)-C(41) -123.8(9)

N(42)-Ni(3)-N(41)-C(41) 56.5(9)

Br(2)-Ni(3)-N(41)-C(41) -37.9(9)

Br(3)-Ni(3)-N(41)-C(41) 154.7(9)

Br(4)-Ni(3)-N(41)-C(41) -136.2(12)

N(41)-Ni(3)-N(42)-C(47) -33.7(10)

Br(2)-Ni(3)-N(42)-C(47) 62.4(10)

Br(3)-Ni(3)-N(42)-C(47) -122.2(9)

Br(4)-Ni(3)-N(42)-C(47) 149.1(9)

N(41)-Ni(3)-N(42)-C(48) 156.9(1 1)

Br(2)-Ni(3)-N(42)-C(48) -107.1 (1 1)

Br(3)-Ni(3)-N(42)-C(48) 68.3(1 1)

Br(4)-Ni(3)-N(42)-C(48) -20.4(1 1)

Ni(l)-N(l)-C(l)-C(6) -132.5(12)

Ni(l)-N(l )-C( l)-C(2) 47.5(14)

C(6)-C(l)-C(2)-C(3) -6(2)

N(l)-C(l)-C(2)-C(3) 173.5(1 1)

C(6)-C(l)-C(2)-C(7) 172.6(13)

N(l)-C(l)-C(2)-C(7) -7.4(19)

C(l)-C(2)-C(3)-C(4) 4(2) C(7)-C(2)-C(3)-C(4) -175.4(13)

C(2)-C(3)-C(4)-C(5) -1(2)

C(3)-C(4)-C(5)-C(6) 0(2)

C(2)-C(l)-C(6)-C(5) 6(2)

N(l)-C(l)-C(6)-C(5) -173.7(11)

C(4)-C(5)-C(6)-C(l) -3(2)

C(8)-N(2)-C(7)-0(l) 6.5(16)

Ni(l)-N(2)-C(7)-0(1) 179.7(8)

C(8)-N(2)-C(7)-C(2) -168.0(13)

Ni(l)-N(2)-C(7)-C(2) 5.2(19)

C(9)-0(l)-C(7)-N(2) 6.6(17)

C(9)-0(l)-C(7)-C(2) -178.2(13)

C(3)-C(2)-C(7)-N(2) 157.1(13)

C(l)-C(2)-C(7)-N(2) -22(2)

C(3)-C(2)-C(7)-0(l) -17.5(18)

C(l)-C(2)-C(7)-0(1) 163.5(12)

C(7)-N(2)-C(8)-C(l l) 102.0(13)

Ni(l)-N(2)-C(8)-C(l l) -70.9(14)

C(7)-N(2)-C(8)-C(10) -133.9(13)

Ni(l)-N(2)-C(8)-C(10) 53.3(17)

C(7)-N(2)-C(8)-C(9) -15.3(15)

Ni(l)-N(2)-C(8)-C(9) 171.8(10)

C(7)-0(l)-C(9)-C(8) -15.5(17)

N(2)-C(8)-C(9)-0(l) 18.4(16)

C(l l)-C(8)-C(9)-0(1) -95.5(16)

C(10)-C(8)-C(9)-O(l) 138.6(15)

Ni(2)-N(21)-C(21)-C(26) 130.0(12)

Ni(2)-N(21)-C(21)-C(22) -49.3(13)

C(26)-C(21)-C(22)-C(23) 2.5(19)

N(21)-C(21)-C(22)-C(23) -178.3(12)

C(26)-C(21)-C(22)-C(27) -172.7(13)

N(21)-C(21)-C(22)-C(27) 6.6(18)

C(21)-C(22)-C(23)-C(24) -2(2)

C(27)-C(22)-C(23)-C(24) 173.5(14)

C(22)-C(23)-C(24)-C(25) -1(2)

C(23)-C(24)-C(25)-C(26) 2(2) C(22)-C(21)-C(26)-C(25) -1(2)

N(21)-C(21)-C(26)-C(25) 179.8(12)

C(24)-C(25)-C(26)-C(21) -1(2)

C(28)-N(22)-C(27)-0(21 ) -4.8(15)

Ni(2)-N(22)-C(27)-0(21) -177.8(8)

C(28)-N(22)-C(27)-C(22) 174.0(14)

Ni(2)-N(22)-C(27)-C(22) 1.0(19)

C(29)-0(21)-C(27)-N(22) -4.2(15)

C(29)-0(21)-C(27)-C(22) 176.8(12)

C(23)-C(22)-C(27)-N(22) -153.0(14)

C(21)-C(22)-C(27)-N(22) 22(2)

C(23)-C(22)-C(27)-0(21) 25.7(18)

C(21)-C(22)-C(27)-0(21) -159.2(11)

C(27)-N(22)-C(28)-C(29) 11.3(14)

Ni(2)-N(22)-C(28)-C(29) -176.7(9)

C(27)-N(22)-C(28)-C(31) 129.2(14)

Ni(2)-N(22)-C(28)-C(31) -58.8(17)

C(27)-N(22)-C(28)-C(30) -109.0(14)

Ni(2)-N(22)-C(28)-C(30) 63.0(15)

C(27)-0(21)-C(29)-C(28) 1 1.2(14)

N(22)-C(28)-C(29)-0(21) -13.3(14)

C(31)-C(28)-C(29)-0(21) -132.0(13)

C(30)-C(28)-C(29)-O(21) 104.6(15)

Ni(3)-N(41)-C(41)-C(46) 129.9(1 1)

Ni(3)-N(41)-C(41)-C(42) -50.9(14)

C(46)-C(41)-C(42)-C(43) 2(2)

N(41 )-C(41 )-C(42)-C(43) -177.3(11)

C(46)-C(41)-C(42)-C(47) -173.7(13)

N(41)-C(41)-C(42)-C(47) 7.1(19)

C(41)-C(42)-C(43)-C(44) -2(2)

C(47)-C(42)-C(43)-C(44) 173.9(14)

C(42)-C(43)-C(44)-C(45) 2(2)

C(43)-C(44)-C(45)-C(46) -1(2)

C(42)-C(41)-C(46)-C(45) -2(2)

N(41)-C(41)-C(46)-C(45) 177.5(12)

C(44)-C(45)-C(46)-C(41) 1(2) C(48)-N(42)-C(47)-0(41) -4.2(15)

Ni(3)-N(42)-C(47)-0(41) - 175.8(8)

C(48)-N(42)-C(47)-C(42) 175.4(13)

Ni(3)-N(42)-C(47)-C(42) 3.8(19)

C(49)-0(41)-C(47)-N(42) -10.5(15)

C(49)-0(41)-C(47)-C(42) 169.9(12)

C(41)-C(42)-C(47)-N(42) 20(2)

C(43)-C(42)-C(47)-N(42) -155.3(13)

C(41)-C(42)-C(47)-0(41) -160.0(12)

C(43)-C(42)-C(47)-0(41) 24.3(18)

C(47)-N(42)-C(48)-C(51) 135.8(12)

Ni(3)-N(42)-C(48)-C(51) -53.7(15)

C(47)-N(42)-C(48)-C(50) -102.2(12)

Ni(3)-N(42)-C(48)-C(50) 68.4(14)

C(47)-N(42)-C(48)-C(49) 16.0(14)

Ni(3)-N(42)-C(48)-C(49) -173.5(9)

C(47)-0(41)-C(49)-C(48) 19.9(14)

N(42)-C(48)-C(49)-0(41) -21.4(14)

C(51)-C(48)-C(49)-0(41) -139.8(13)

C(50)-C(48)-C(49)-O(41) 92.3(14)

Figure 1-B is an ORTEP diagram of the cationic component of 3.

Figure 1-C is a full ORTEP diagram of 3. The X-ray characterisation of complex 1 was carried out at the University of

Toronto's X-ray diffraction facility according to the techniques described in: M.W. Chojnacka, A.J. Lough, R.S. Wylie and R.A. Gossage, J. Molec. Struct., 2011, 991, 158- 161. The diffraction data for complexes 2 and 3 was obtained and refined at the Department of Chemistry, University of Saskatchewan in a similar fashion to that described in: R.C. Jones, M.W. Chojnacka, J.W. Quail, M.G. Gardiner, A. Decken, B.F. Yates and R.A. Gossage, Dalton Trans., 2011, 40, 1594-1600.

All polymerisations were carried out under a nitrogen (N ₂ (g)) atmosphere using standard Schlenk techniques in a flame dried 50 or 100 mL Schlenk flask containing a magnetic stir bar. Control Polymerisations

Example 4 - Styrene and MAO (no pre-catalyst cluster)

For a control, polymerisation of styrene with only MAO and the styrene monomer was undertaken. Styrene and MAO were added to a flame dried flask containing a stir bar under Schlenk techniques. Styrene (5 mL, 40mmol) was added first via syringe. MAO (0.80 mmol, 0.6 mL) was added last via syringe. Precipitation in a large excess of MeOH yielded 3.7% PS and a PDI of 6.

Example 5 - Pre-catalyst cluster 1 and styrene (no MAO)

A reaction containing pre-catalyst cluster 1 (crude, dried under vacuum; 0.26 mmol, 210 mg) and the styrene monomer (5 mL, 40 mmol) yielded no polymer.

Example 6 - Methylmethacrylate (MMA) and MAO (no pre-catalyst cluster)

A control reaction of MMA (5 mL, 47 mmol) with MAO (0.94 mmol, 0.6 mL) yielded no polymer.

The polymerisation of styrene and MMA was attempted without the use of the nickel pre-catalyst clusters with only MAO, toluene and monomer present for the reaction. The control polymerisation of styrene gave only a yield of 3.7% PS and a very broad PDI (>6) after a reaction time of 8 d. The same control with MMA produced no pMMA. A control of styrene with the nickel pre-catalyst cluster 1 only and no MAO was also performed. This control did not yield any polymer. It appears that both initiator nickel pre-catalyst and initiator (MAO) are required for adequate polymerisation.

Polymerisation of Styrene

Example 7 - Catalyst System with crude Pre-catalyst cluster 1 Catalyzed Polymerisation of Styrene

After being dried under vacuum for 20 minutes, pre-catalyst cluster 1 was added (0.27 mmol, 190 mg) to the reaction flask. Styrene (40 mmol 5 mL) was added next via syringe. A 10% toluene solution of MAO (0.80 mmol, 0.6 mL) was syringed in drop-wise to initiate the polymerisation. After 8 d, PS was precipitated in a large excess of MeOH and collected by filtration. The PS was then dissolved in THF, re-precipitated in MeOH and then dried under vacuum. The yield of PS was determined by gravimetry. Yield of PS was 62%. Typical M _w of a PS sample polymerized using the crude form of 1 was 190,000 Daltons with an average PDI of 1.7. Example 8 - Catalyst System with Crystalline Pre-catalyst cluster 1 Catalyzed Polymerisation of Styrene

Pre-catalyst cluster 1 was added (0.26 mmol, 210 mg) to the reaction flask. After being crushed with a mortar and pestle before being dried under vacuum for 20 min, pre- catalyst 1 was added (0.26 mmol, 210 mg) to the reaction flask. Styrene (40 mmol 5 mL) was then added via syringe. A 10% toluene solution of MAO (0.80 mmol, 0.6 mL) was syringed in drop-wise to initiate the polymerisation. After 8 d, PS was precipitated in a large excess of MeOH and collected by filtration. The PS was then dissolved in THF, re- precipitated in MeOH and then dried under vacuum. The yield of PS was determined by gravimetry. PS polymerized using the crystalline form of 1 was found to be bimodal with yields of 75%. The M _w was 220,238 Daltons and PDI = 4.6.

Example 9 - (Catalyst System with Crystalline Pre-Catalyst cluster 2 Catalyzed Polymerisation of Styrene

Pre-Catalyst cluster 2 was added (powder; 0.12 mmol, 109 mg) to the reaction flask. It was then dried under vacuum for 20 min. Styrene (17 mmol, 2 mL) was then added via syringe. A 10% toluene solution of MAO (0.35 mmol, 0.2 mL) was syringed in drop-wise (about 15 drops per minute) to initiate the polymerisation. After 8 d (RT, ambient pressure under an N ₂ atmosphere), the reaction mixture was precipitated in a large excess of MeOH. The reaction yielded 14% PS by gravimetry. The M _w of the PS was 85,000 Daltons with a PDI of 3.5.

Polystyrene (PS)

Polymerisation of Styrene with {[Ni(C ₆ Hi ₆ N ₂ )] ₃ Cl ₄ OH}Cl (1)

The amount of catalyst 1 was calculated according to one third of 2% of the mol amount of the added monomer due to the pre-catalyst cluster having three Ni. The amount of MAO added was 2% mol of the mol amount of monomer. This amount is equal to a Al/Ni ratio of 1 : 1. Upon addition of MAO to the reaction mixture containing pre-catalyst cluster 1, a colour change of green to red occurred which then persisted for approximately 12 hours afterwards when the crystalline form of pre-catalyst cluster used (as well as any dilution due to solvent addition). Reaction mixtures using the crystalline form appear to retain the red colour for longer periods of time. After 8 d, the reaction mixture is quenched and the polymers precipitated by the addition of MeOH. The active catalyst cluster and/or pre-catalyst cluster by-products are somewhat soluble in MeOH and with the large excesses of the solvent that are used during precipitation and re- precipitation it essentially transfers all active catalyst residue(s) in the solvent. Thus, only a white fluffy powder of PS was recovered. Figure 2 shows a GPC result of a typical PS sample catalyzed using crude pre-catalyst cluster 1 as per Example 7. All three detectors show a monomodal distribution of the polymer and absolute M _w 's of about 190,000 Daltons with a PDI of 1.7 (Figure 2).

Polymerisation of Styrene using {[Ni(C _n Hi ₄ N ₂ 0)] ₃ Cl ₄ OH}Cl (2)

The oxazoline analogue 2 of 1 was also employed in the polymerisation of styrene. The polymerisation yielded 14% PS after 8 days. The M _w of the resulting PS was found to be 85,000 Daltons with a PDI of 3.5. The GPC peaks of this PS were much broader and less refined than those of a 1 polymerized PS Figure 3 provides the GPC peaks of the PS produced as per Example 9.

Crude Versus Crystalline Pre-Catalyst 1

The experiment to test the effect of addition of the crude pre-catalyst vs. crystalline form of 1 (re-crystallized from DCM / hexanes as above) demonstrates that the crystalline form is more active in the polymerisation of styrene. A red colour change persisted with the crystalline form throughout the polymerisation experiment(s) while this red colour of the reaction mixture faded back to green using the powdered crude form . The crystalline form produced (by Example 8) bimodal polystyrene (Figure 4). The crystalline form produced a greater yield after 8 d reaction time of 75% compared to a maximum of 62% with the crude form.

Tacticity

The T _g , T _m , and Ή-NMR PS were examined to determine the tacticity of the synthesized polymer. Figure 5 shows a typical Ή-NMR spectrum of the PS prepared using the crude pre-catalyst cluster 1 as per Example 7. In the 6.3 - 7.3 ppm range, the aromatic protons resonate and in the 2.0 to 1.2 ppm range the methine and methylene protons are identified. For isotactic PS, the shifts of the methylene and methine protons are greater than 1.5 and 2.0 ppm, respectively. The experimental shift of the methylene protons is 1.44 ppm and of the methine proton 1.86 ppm, both indicative of a sPS. The peaks are not well-defined and exhibit broadness which suggests some atactic nature of this PS sample (N. Ishihara, T. Seimiya, M. Kuramoto, M. Uoi, Polym. Prepr. Jpn. 1986, 35, 240-241).

The DSC results are also consistent with a largely sPS. The T _g values for both sPS and iPS are 101°C and the T _m 270°C and 240°C, respectively (S. Yu, X. Yu, Y. Chen, Y. Liu, S. Hong, Q. Wu, J Appl. Polym. ScL, 2007, 105, 500-509). The experimental PS T _g value is 99°C with onsets at 96°C (Figure 6). The T _m for this polymer was found to be 265°C (Figure 7).

Polymerisation of Methyl Methacrylate

Example 10 - Crystalline Pre-Catalyst Cluster 1 catalyzed polymerisation of methylmethacrylate

Pre-catalyst cluster 1 was added first (crude; 0.31 mmol, 225 mg, crystalline; 0.31 mmol, 252 mg). If used as the crude powder it was first dried under vacuum for 20 minutes. If crystalline catalyst was used it was first crushed with a mortar and pestle before being dried under vacuum for 20 minutes. Toluene was added second via syringe. MMA was added third (47 mmol, 5 mL) via syringe. A 10% toluene solution of MAO (0.94 mmol, 0.6 mL) was syringed in drop-wise to initiate the polymerisation. After 3 to 5 d, pMMA was precipitated in a large excess of MeOH and collected by filtration. It was then dissolved in THF, re-precipitated in MeOH and dried under vacuum and pMMA yield was determined by gravimetry. Yields using the crude form of 1 reached 48% after a 5d reaction time. M _w of a pMMA sample polymerized using the crude form of 1 was 203,630 Daltons with a PDI of 1.8. Yield using the crystalline form was 37% after a 3d reaction time. Using the crystalline form of 1 the M _w of the pMMA was 580,000 Daltons with a PDI of 1.9.

In an experiment to observe the polymerisation rate of MMA, a 0.5 mL sample of the reaction mixture was syringed out every 24 h for four consecutive days. On the fifth day additional distilled 5 mL toluene was added in order to dilute the reaction mixture due to the high viscosity of the reaction mixture. The samples were precipitated in MeOH, dissolved in THF, re-precipitated in MeOH and dried under vacuum.

Poly(methyl methacrylate)

The Polymerisation of Methyl Methacrylate with 1 The addition of MAO to a MMA, toluene and 1 reaction mixture does not produce a colour change during the polymerisation process. The pMMA mixture becomes steadily more viscous each day and thus the use of a solvent is desirable to reduce this viscosity. Toluene was chosen for this purpose due to literature precedence. The GPC results show clean monomodal peaks (Figure 8).

The increasing molecular weight of the polymer can be seen in Figure 9. A sample was extracted every 24 h for five consecutive days. There is also a general decrease in PDI with the sample extracted at day 1 having a PDI of 2.3 and at day 5 a PDI of 1.6. This may be due to a joining of polymer chains with increasing reaction time and decreasing monomer availability. The graph in Figure 9 shows a steady increase in M _w with the allowed reaction time reaching about 7.3 lO ⁵ Daltons by day 5 at which point the high viscosity of the reaction mixture required additional toluene in order for a sample to be extracted.

Tacticity

Poly(methyl methacrylate) tacticity can be determined by a collective examination of the Ή-NMR, ¹³ C-NMR, T _g and T _m . As seen in Figure 10 the typical pMMA product using 1, exhibits three different groups of protons. At 3.61 ppm, a sharp singlet corresponding to the three methyl group protons directly connected to the methoxy group (H _a ), can be seen. The a-methyl resonances (H _c ) appear at 0.86 ppm and 1.03 ppm which correspond to syndiotactic and atactic pMMA respectively and are found in a ratio of 2.12 : 0.90 or about 70% syndiotactic. The methylene group protons (¾) appear as a sharp singlet and as a cluster of smaller broader resonances. The singlet is centred at 1.82 ppm and integrates for approximately 1.14 protons while the broader area has 6 _H values of 1.89, 1.91, 1.94 and 1.98 ppm with a combined integration of 0.63 protons. The methylene group signals suggest that the pMMA is 64% syndiotactic and the rest (36%) atactic [D. Braun, H. Cherdron, M. Rehahn, H. Ritter, B. Voit, Polymer Synthesis: Theory and Practice; Springer- Verlag: Berlin, 2005]. The integrations of both ¾ and H _c suggest 65-75% syndio-tacticity.

The DSC T _g data for a crystalline 1 catalyzed pMMA sample is shown in Figure 11 The DSC shows a large heat transition increase immediately after the T _g and peaking at 178°C which appears to be a melt however, further characterization is needed. A predominantly isotactic pMMA (95%) has a T _g of 41.5°C and a more syndiotactic (81%) pMMA has a T _g of 134°C (W. Wunderlich, Physical Constants of Poly(Methyl Methacrylate), 2005, 87-90). The experimental T _g was about 136°C indicating the presence of a highly syndiotactic polymer. The presence of about 81% syndiotactic polymer is suggested although the 1H-NMR data suggests a 64% syndiotactic pMMA. The discrepancy is due to variation in equipment sensitivity.

Example 1 1 - Catalyst System with Crystalline Pre-catalyst cluster 1 Catalyzed Polymerisation of Methylacrylate

After being dried under vacuum for 20 minutes, pre-catalyst cluster 1 was added (0.26 mmol, 209 mg) to the reaction flask. 5 mL of Toluene was then added to the flask via syringe and the solution was stirred. A 10% toluene solution of MAO (0.90 mmol, 0.6 mL) was syringed in drop-wise to activate the catalyst and stirred for 2hrs.

Methylacrylate (45 mmol, 4.08 mL) was added next via syringe. After 8 d, the toluene mixture was precipitated in a large excess of MeOH and the polymethacrylate collected by filtration. The recovered polymethacrylate was transparent and observed to be highly cross-linked and could not be readily redissolved in polar solvents (THF). The recovered polymethacrylate was then dried under vacuum and analyzed by FT-IR which confirmed the presence of C=0 stretch at 1620 cm ^"1 for the polymethacrylate. The yield of polymethacrylate was determined by gravimetry. Yield of polymethacrylate was 13%.

The following is a chart outlining the examples of the present invention and associated data.

Generally, it was observed that exposure of the polymerisation reaction to air causes quenching of the polymerisation and little or no yield depending on the time of exposure. MAO is typically used in large excess in olefin polymerisations both as an activator and as a scavenger. The low Al/Ni (MAO: Nickel cluster) ratio of 1 :1 in the present invention is therefore unusual in comparison to the typical ratios of hundreds to thousands of equivalents of Al to the transition metal. For example, Schellenberg found that styrene does not polymerize using a half Titanocene catalyst and MAO initiator system with ratios lower than 6:1 of Al/Ti (L. Schellenberg, Eur. Polym. J. 2005, 41, 3026-3030).

Polymerisation of MMA may be faster than that of PS as can be seen by the higher M _w of 700,000 Daltons after a reaction time of only 5 d compared to 300,000 after 8 d. This can also be seen by the rapidly increasing viscosity of the pMMA reaction mixture. If the polymerisation is occurring via a transition metal-mediated path as proposed, this may be due to an attraction of the polar monomer towards the cationic transition metal centre.

The polymerisations appear to be living judging by the increasing M _w observed every day of the pMMA samples. A living reaction is also characterized by a relatively narrow PDI and the PDI of PS and pMMA catalyzed by 1 both crude and crystalline demonstrate a relatively narrow PDI.

The 1H-NMR and DSC that have been obtained give strong evidence of predominantly syndiotactic polymers of both PS and pMMA. In particular the high T _m of 265°C of crystalline 1 polymerized PS demonstrates the high crystallinity of the syndiotactic polymer.

These results clearly indicate that the catalyst system of the present invention is useful for the selective and inexpensive production of sybstantially sydio-tactic rich polymers.

While the foregoing provides a detailed description of a preferred embodiment of the invention, it is to be understood that this description is illustrative only of the principles of the invention and not limitative. Furthermore, as many changes can be made to the invention without departing from the scope of the invention, it is intended that all material contained herein be interpreted as illustrative of the invention and not in a limiting sense.