Synthesis and characterization of cobalt (II) complexes with the ligand derived from salicylaldehyde and 3-(4e-methoxyphenyltelluro) propylamine

Abstract

A potentially tridentate (Te, N, 0) Schiff base type hybrid ligand, 1-(2'-hydroxyphenyl)-5- (4"-methoxyphenyltelluro )-2- azapent-1-ene (L_a) has been synthesized by the condensation of salicylaldehyde with (4-methoxyphenyltelluro) propylamine in an inert atmosphere and characterized. Its complexes with anhydrous CoBr2 of the types CoBnLa (1), CoBr₂ (L_a)₂(2), CoBr(L_aH) (3) and CoBr(L_a)₂. BPh₄ (4) are obtained under different sets of experimental conditions. Although Co(ll) in none of the above complexes including the complex CoBr(L_b)₂BPh₄(5) formed with (4- methoxyphenyltelluro ) propylamine (L_b), undergo aerial oxidation, it does when air is bubbled through a solution of anhydrous cobalt bromide, (4-methoxyphenyltelluro) ethylamine (Le) and NaBPh₄ in nitromethane resulting in the formation of [CoBr₂(L_c)₂]BPh₄ (6). These complexes have been characterized by elemental analyses, conductance and magnetic susceptibility measurements, electrochemical studies, FAB mass (2 and 3 only) and IR spectroscopy.