Showing papers by "Edward I. Stiefel published in 2002"

[PdS2C2(COOMe)2](6n) (n = 0, -1, -2, -3, -4): hexanuclear homoleptic palladium dithiolene complexes.

Abstract: Reaction of a stoichiometric equivalent of the zinc-dithiolene complex, (tmeda)ZnS2C2(COOMe)2 (tmeda = tetramethylethylenediamine), with (MeCN)2PdCl2 results in a 1:1 homoleptic dithiolene that forms the hexanuclear cluster [PdS2C2(COOMe)2]6 (1). X-ray structure analysis of 1 indicates a Pd6S12 core comprised of six face-centered palladium atoms and 12 edge-centered sulfur atoms situated on an imaginary approximate cube. Complex 1 undergoes four distinct and reversible one-electron redox steps in dichloromethane at -186, -484, -1174, and -1524 mV versus a standard calomel electrode (ferrocenium+/ferrocene redox couple 409 mV). The two-electron reduction product of 1, [Bu4N]2[(PdS2C2(COOMe)2)6] (2), has been chemically isolated and characterized.

Sulfur-containing and sulfur-nitrogen-containing catalysts for polymerization of olefins and polar monomers

Abstract: The inventions disclosed herein are catalyst systems comprising a complex having one of the formulas LMX 1 X 2 and LML′ and an activating cocatalyst, and use of the catalyst system in polymerizing olefinic monomers. In either of the foregoing formulas, L is a chelating ligand containing sulfur donors; M is a transition metal selected from either copper, silver, gold, manganese, iron, cobalt, palladium or nickel; X 1 and X 2 are independently selected from either halides, hydride, triflate, acetate, borate, alkyl, alkoxyl, cycloalkyl, cycloalkoxyl, aryl, thiolate, carbon monoxide, cyanate or olefins; and L′ is a bidentate ligand selected from either dithiolene, dithiolate, diphosphine, bisimine, bispyridine, phenanthroline, oxolate, catecholate, thiolatoamide, thiolatoimine or thiolatophosphine.