The structurally characterised silyl complexes, Os(κ2-S2CNMe2)(SiMeCl2)(CO)(PPh3)2 and Os(κ2-S2CNMe2)(SiCl3)(CO)(PPh3)2, which have remarkably unreactive Si–Cl bonds

Treatment of Os(κ2-S2CNMe2)H(CO)(PPh3)2 with HSiMeCl2 or HSiCl3 gives in high yield Os(κ2-S2CNMe2)(SiMeCl2)(CO)(PPh3)2 (1) or Os(κ2-S2CNMe2)(SiCl3)(CO)(PPh3)2 (2), respectively. The crystal structures of both compounds have been determined and the Os–Si distances are 2.3672(10) Å for 1 and 2.3449(12) Å for 2. In solution, and under forcing conditions, both compounds are extraordinarily unreactive towards hydroxide ions.