Metallacyclic complexes with ortho-stannylated triphenylphosphine ligands, LnOs(κ2(Sn,P)-SnMe2C6H4PPh2), derived from thermal reactions of the five-coordinate complex, Os(SnMe3)Cl(CO)(PPh3)2

The coordinatively unsaturated trimethylstannyl complex, Os(SnMe3)Cl(CO)(PPh3)2 undergoes a thermal reaction to form a mixture of Os(κ2(Sn,P)-SnMeClC6H4PPh2)(κ2(C,P)-C6H4PPh2)(CO)(PPh3) (1) and Os(κ2(Sn,P)-SnMe2C6H4PPh2)(κ2(C,P)-C6H4PPh2)(CO)(PPh3) (2), each complex containing both ortho-stannylated and ortho-metallated triphenylphosphine ligands. It is proposed that the ortho-stannylation reaction could proceed through the intermediacy of a stannylene complex.