Reactions between Co(II) and bis(diphenylphosphino)methane in the presence of NaBH4 or NaBH3CN

Abstract

Reactions between Co(II) and bis(diphenylphosphino)methane (dppm) in the presence of NaBH4 or NaBH3CN are described. The main products are the Co(I) complex, CoCl(dppm)3, and Co(III) complexes of the type [CoHX(dppm)2]Y (where X = Cl, Y = Cl or BPh4; X = Y = Br; X = Y = I; X = BH3CN, Y = BH3CN, ClO4, or BPh4). The former has been shown by X-ray crystallography to contain a Co atom tetrahedrally coordinated by a Cl and three P atoms from three monodentate dppm ligands. Possible mechanisms for the formation of Co(III) are discussed.