Synthesis and Structure of Low-valent η4 -Cinnamaldehyde Cobalt Complexes

Abstract

Three η4-(C=C–C=O) coordination cobalt(I) complexes 1–3 were synthesized by the reactions of cinnamaldehyde, p-fluorocinnamaldehyde, and p-chlorocinnamaldehyde with CoMe(PMe3)4. Complex 4 as η2-(C=C) coordination was prepared by the reaction of chalcone with Co(PMe3)4. The structures of complexes 1–4 were confirmed by single-crystal X-ray diffraction. Although the reactions didn't undergo C–H bond activation and decarbonylation, the formation of complexes 1–4 deepens our understanding of the reactions between α,β-unsaturated aldehyde or ketone with low-valent central cobalt atom.