Metal–ligand cooperativity of a Co–P moiety†
A novel cobalt system featuring a Co–P moiety has been synthesized to study its metal–ligand cooperativity. A reversible conversion of a phosphide group to a P–P bond found in a dimeric cobalt(I) complex involves electron transfer between Co and P, in which a single electron transfer is successfully coupled with a redox change in each cobalt ion. Upon coordination of a π-acidic ligand such as acetonitrile and isocyanide at the cobalt site, the transformation of a dimeric to a monomeric cobalt complex occurs, which involves the migration of a phenolate group. During the conversion, a P–P bond was cleaved and converted to phosphide and phosphinite. Current Co–P metal–ligand cooperativity presented in this work has been explored structurally, spectroscopically and theoretically.