N-Heterocyclic carbene complexes of cyclopentadienylnickel(II): Synthesis, structure and catalytic activity in styrene polymerization

• Published in: Journal of molecular catalysis. A, Chemical Vol. 257; no. 1; pp. 118 - 123
• Main Authors: Buchowicz, Włodzimierz, Kozioł, Andrzej, Jerzykiewicz, Lucjan B., Lis, Tadeusz, Pasynkiewicz, Stanisław, Pęcherzewska, Aleksandra, Pietrzykowski, Antoni
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.09.2006; Elsevier
• Subjects: Applied sciences; Crystal structure; Exact sciences and technology; N-Heterocyclic carbene; Nickel; Organic polymers; Physicochemistry of polymers; Polymerization; Preparation, kinetics, thermodynamics, mechanism and catalysts; Styrene; Polymerization; Nickel; Styrene; N-Heterocyclic carbene; Crystal structure; Ligand effect; Imidazole derivatives; Complex catalyst polymerization; Complex catalyst; Experimental study; Lattice parameters; Solution polymerization; Carbene; Reaction mechanism; Styrene polymer; Hapto complex; Chemical synthesis; Catalyst activity; Halo complex; Nickel II Complexes; Crystalline structure
• ISSN: 1381-1169; 1873-314X
• DOI: 10.1016/j.molcata.2006.05.061

Cyclopentadienylnickel(II) complexes with N-heterocyclic carbenes [NiCp(X)(NHC)] (X = Cl, Br or CH 3), combined with MAO have been used as catalysts for the polymerization of styrene. The catalytic activity of the systems depended mainly on the ease of the abstraction of X substituent by MAO and the stabilization of cationic species [NiCp(NHC)] +. The molecular structures of three title complexes have been determined by single-crystal X-ray diffraction. All three compounds crystallize in monoclinic crystal system with four molecules in the unit cell. Their structural parameters have been compared with data reported for similar complexes. Two of these complexes [NiCp(CH 3)(IMes)] and [NiCp(CH 3)(SIMes)] are the first examples of structurally characterized (unsubstituted)-cyclopentadienylnickel methyl compounds.