Cobalt(III) Schiff base complex: Synthesis, X-ray structure and aerobic epoxidation of olefins

A new Co(III) Schiff-base complex, [Co(HL)2]NO3·H2O (1) (H2L = 1-(N-3-methoxy-salicylideneimino)-ethane-2-ol), has been synthesized and characterized by several physicochemical methods. X-ray crystal structure analysis revealed that complex 1 features a distorted octahedral coordination geometry and the metal center is surrounded by two tridented N,O,O-donor Schiff base ligands (HL−). [Co(HL)2]NO3·H2O (1) is capable of activating dioxygen in air to catalyze the epoxidation of various alkenes using isobutraldehyde as a co-reductant under homogeneous conditions. It was observed that the yield of the epoxides and their selectivity is highest in acetonitrile medium.

Graphical abstractReaction of Co(II) nitrate with the Schiff base ligand H2L (1-(N-3-methoxy-salicylideneimino)-ethane-2-ol) in ethanol led to a new octahedral Co(III) complex, [Co(HL)2]NO3·H2O, whose structure and catalytic activity in the aerobic epoxidation of various alkenes are presented.Figure optionsDownload full-size imageDownload as PowerPoint slide