Metal complexes of aromatic Schiff bases. Part II. Cobalt complexes of N-(2 -dialkylaminophenyl)salicylideneimines

Abstract

The Schiff bases, H–SalphenNR₂, derived from salicylaldehyde and NN-dialkyl-o-phenylenediamines, where R = Me, Et, Prⁿ, and Buⁿ react with cobalt acetate to give complexes which have been assigned a structure involving bridging acetate groups. Only when R = Me were complexes isolated with cobalt halides, the far-infrared spectra of which suggests halogen-bridged dimers of SalphenNMe₂·Co^II·X, in which the cobalt(II) ion is pentaco-ordinate. Bis(salicylaldehydato)cobalt(II) reacts stepwise with NN-dimethyl- and NN-diethyl-o-phenylenediamine to give SalphenNR₂·Co^II·Sal and (SalphenNR₂)₂Co^II. The salicylaldehyde moiety in SalphenNR₂·Co^II·Sal reacts with other amines to give mixed 2:1 Schiff-base complexes.