On the reduced form of (imidazole-N3)(N-salicylidene-alaninato-O,N,O′) copper(II)

The geometries of the (imidazole-N3)(N-salicylidene-alaninato-O,N,O′) copper(II) and of its anion as well as of six models of its neutral hydrogenated form with the additional hydrogen at oxygen or nitrogen sites modeling its reduced copper(I) form are optimized using the gaussian 98 program package at B3LYP/6-31G* level of theory. Energy data indicate the highest stability of the structures with additional hydrogen bonded to some of carboxyl oxygens with released (or significantly weakened) Cu-O(carboxyl) bond. Hydrogen atom is inserted into this bond in the second most stable model system (with ca. 1 kJ/mol higher energy).