The synthesis of mixed-valence dirhodium carbonyl complexes, and the X-ray crystal structures of [{Rh(CO)(PPh3)(µ-RNNNR)}2] and [{Rh(CO)(PPh3)(µ-RNNNR)}2][PF6](R =p-tolyl)

Abstract

X-Ray structural studies on [{Rh(CO)(PPh₃)(µ-RNNNR)}₂]^Z+(R =p-tolyl, z= 0 and 1) show that the mixed-valence cation is formed by electron-loss from a metal–metal anti-bonding orbital; the asymmetric compounds [Rh₂(CO)₂L(PPh₃){µ-PhNC(Me)NPh}₂]^Z+[L = P(OPh)₃, AsPh₃, etc., z= 0 and 1] result form the oxidatively induced substitution of [Rh₂(CO)₃(PPh₃){µ-PhNC(Me)NPh}₂].