SURFACE-MEDIATED ORGANOMETALLIC SYNTHESIS - HIGH-YIELD PREPARATIONS OF (IR(CO)3CL)N, [RH(CO)2CL]2, [RU(CO)3CL2]2, [OS(CO)3CL2]2, [IR4(CO)12], AND [RH6(CO)16] BY REDUCTIVE CARBONYLATION, UNDER MILD CONDITIONS, OF SILICA-SUPPORTED METAL CHLORIDES

{Ir(CO)3Cl}n, [Rh(CO)2Cl]2, [Ru(CO)3Cl2]2, and [Os(CO)3Cl2]2 have been synthesized in high yield from the corresponding metal trichloride supported on a silica surface by reductive carbonylation at atmospheric pressure. With IrCl3·nH2O, the synthesis can be directed to give selectively [Ir4(CO)12] by working at 70°C in the presence of CO and H2O. [Rh6(CO)16] has also been prepared by reductive carbonylation at room temperature of silica-supported [Rh(CO)2Cl]2. These surface-mediated synthetic methods give yields comparable or often higher than those of the traditional solution syntheses.