Reactivity of 2-methyl-3-butenenitrile in the presence of catalytic amounts of various cobalt complexes in ionic liquid

The behavior of 2-methyl-3-butenenitrile (2M3BN) in the presence of catalytic amount of several cobalt complexes was evaluated. Irrespective of the nature of cobalt complexes and the experimental conditions (presence of ligand [such as P(OPh)(3) or pyridine], or/and of Lewis acid [ZnCl2, AlCl3], organic solvent or ionic liquid), the product of isomerization 2-methyl-2-butenenitrile was obtained instead of the expected rearranged product 3-pentenenitrile (3PN). This result was explained by the activation of C-H bond instead of C-CN bond. With 3PN, the first example of a reversible cleavage of the C-CN with complex derived from Co+ was evidenced. (c) 2005 Elsevier B.V. All rights reserved.