Synthesis and structure of 16-electron rhodium(III) catalysts for transfer hydrogenation of a cyclic imine: mechanistic implications

Significant Rh-NH pi-bonding in formally 16-electron (eta(5)-C5Me5)Rh(XNC6H4NX') (X, X' = H or Ts) is shown by structural features and by DFT calculations; (eta(5)-C5Me5)Rh(TsNC6H4NH) is the fastest transfer hydrogenation catalyst of the three complexes and generates a formate complex under catalytic conditions.