Surface-mediated organometallic synthesis: High-yield and selective syntheses of neutral and anionic ruthenium carbonyl clusters by controlled reduction of silica-supported RuCl3 in the presence of Na2CO3 or K2CO3

[Ru-3(CO)(10)Cl-2], [Ru-3(CO)(12)], [H4Ru4(CO)(12)], [H3Ru4(CO)(12)](-), [HRu6(CO)(18)](-), and [RU6C(CO)(16)](2-) have been synthesized in good or high yields by one-step or two-step (with the surface species [Ru(CO)(3)Cl-2(HOSi=)] as intermediate) one-pot controlled reduction of RuCl3 supported on silica in the presence of alkali carbonates. The selectivity of the reaction is controlled by the (i) nature and quantity of the alkali carbonate (Na2CO3 or K2CO3), (ii) manner by which the alkali carbonate is deposited on the silica surface, (iii) gas-phase composition (GO, CO + H-2, or CO + H2O), (iv) temperature, and (v) reaction time. The unusual selectivity can be explained by the initial formation of [Ru(CO)(x)(OH)(2)](n), (x = 2, 3) which, under CO, aggregates first to [Ru-3(CO)(12)], key intermediate for the synthesis in situ of various ruthenium carbonyl clusters on the silica surface.