The reactive intermediate of catalytic borohydride reduction by Schiff base-cobalt complexes.
The key reactive intermediate of borohydride reduction catalyzed by Schiff base-cobalt complexes is proposed to be the dichloromethylcobalt hydride with a sodium cation, based on experimental and theoretical studies. It was revealed that chloroform is not the solvent but the reactant that activates the cobalt catalyst. The substrate carbonyl compounds are fixed and activated by the alkali cation, which is captured by the oxygen atoms of the planar ligand and the chlorine atom of the axial ligand, and attacked by the hydride on the cobalt atom via a six-membered-like transition state to afford the corresponding alcohol.
Iwakura
Izumi
I
Department of Chemistry, Faculty of Science and Technology, Keio University, Hiyoshi, Kohoku-ku, Yokohama 223-8522, Japan.
Hatanaka
Miho
M
Kokura
Ai
A
Teraoka
Haruna
H
Ikeno
Taketo
T
Nagata
Takushi
T
Yamada
Tohru
T