Activation of - N=CH - bond in a Schiff base by divalent nickel monitored by NMR evidence

Abstract

The Schiff base, 2-salicylidene-4-aminophenyl benzimidazole in ethanol undergoes activation of -N=CH- bond by Ni 2+ in the presence of ammonia or primary alkyl amine to produce nickel complexes of the formula Nio-C 6H 4(O)CH NR 2. n H 2O R=H, Me; n=0; R=Et, n=0.5 and 4-aminophenyl benzimidazole. The products have been identified by elemental analysis, magnetic susceptibility measurements and IR, ESR, mass and extensive NMR spectral studies. The possible mechanism for the activation of -N=CH - bond has also been proposed. Copyright © 2012 John Wiley & Sons, Ltd