D. McGuinness, W. Mueller, P. Wasserscheid
2002
Citations
0
Influential Citations
128
Citations
Quality indicators
Journal
Organometallics
Abstract
Nickel(II) heterocyclic carbene complexes of the formula NiI2(carbene)2 (carbene = 3-methyl-1-propylimidazolin-2-ylidene (1), 1-butyl-3-methylimidazolin-2-ylidene (2), 1-isopropyl-3-methylimidazolin-2-ylidene (3), 1,3-diisopropylimidazolin-2-ylidene (4)) have been prepared and fully characterized by both spectroscopic methods and single-crystal X-ray structure analysis. All complexes have “square-planar” nickel environments, with the donor atoms pairwise trans, all obligate, except for one of the two independent molecular types found in 2, in which, with different substituents at the nitrogen atoms, the two rotamers are observed as independent molecules in the one crystal. Complexes 1−4 were tested as catalysts for propene and 1-butene dimerization in both toluene and an imidazolium−chloroaluminate ionic liquid. While the complexes are inactive to sparingly active in toluene, highly active catalysts are produced in the ionic liquid. In all cases the complexes are more active toward 1-butene dimerization t...