title: Unusual cationic trinuclear nickel clusters incorporating oxazolines or N,N,N',N'-tetramethylethylene-1,2-diamine: applications in olefin polymerization.
abstract: The synthesis and characterization of two rare examples of the nickel(II)-containing trinuclear clusters of the general formula μ(3)-halido-μ(3)-hydroxotris(μ-halido)tris(L) trinickel(II) halide [halide = Cl (2), Br (3); L = 4,4-dimethyl-2-(o-anilinyl)-2-oxazoline] are described. These materials are compared and contrasted to the "parent" chloride salt (1) of this series (L = N,N,N',N'-tetramethylethylene-1,2-diamine and halide = Cl) and its congeners; 2 and 3 represent the first oxazoline-containing clusters of this structural class. Both 1 and 2 are shown to be active catalysts for the polymerization of olefins (styrene, methyl methacrylate, etc.) using a stoichiometric equivalent of methylaluminoxane as the copromoter, a situation that gives good yields of syndiotactic rich polymers. Density functional theory (B3LYP/6-31G*/LANL2DZ) is employed to hypothesize the likely origin of the activity demonstrated by these compounds.
authors.affiliation: Department of Chemistry & Biology, Ryerson University, 350 Victoria Street, Toronto, Ontario M5B 2K3, Canada.
authors.forename: Sanja
authors.initials: S
authors.lastname: Resanović
authors.forename: R Stephen
authors.initials: RS
authors.lastname: Wylie
authors.forename: J Wilson
authors.initials: JW
authors.lastname: Quail
authors.forename: Daniel A
authors.initials: DA
authors.lastname: Foucher
authors.forename: Robert A
authors.initials: RA
authors.lastname: Gossage