Preparation of N-salicylideneamino-acid and -ester complexes of oxovanadium-(IV) and -(V)

Abstract

Bis(salicylaldehydato)aquo-oxovanadium(IV) and its pyridine analogue have been prepared. Reaction of the former with glycine ethyl ester gave oxobis-[N-(ethoxycarbonylmethyl)salicylidineiminato]vanadium(IV) which was converted by heating in methanol into the analogous methyl ester complex. Prolonged heating of this complex in aqueous methanol led to hydrolysis of the ester and oxidation to vanadium(V). The atmospheric oxidation in alcohols of oxo-[N-(carboxyalkyl)salicylidineiminato]aquovanadium(IV) complexes to mono- or bi-nuclear oxovanadium(V) species was also studied.