Use of the cationic fragments [Ru(eta(5)-C5H5) (MeCN)(3)](+) and [M(eta(6)-C6H5R)(MeCN)(3)](+) (M=Os, Ru; R = H, Me) as ionic coupling reagents in the synthesis of the clusters [Os4M2(CO)(12)(eta(6)-C6H5R)], [OS4M(CO)(12)(eta(6)-C6H6)(Au(2)dppm)] and [Os5Ru(CO)(15)(eta(5)-C5H5)(AuPPh3)]

The clusters [H2Os4M(CO)(12)(eta(6)-C6H6)] (M=Os, Ru) may be deprotonated to generate anions [Os4M(CO)(12)(eta(6)-C6H6)](2-) which react with [M'(eta(6)-C6H5R) (MeCN)(3)](2+) (M'=Os, Ru; R=H, Me) to give the bicapped tetrahedral clusters [Os-4(CO)(12) MM'(eta(6)-C6H5R)(2)]. Whereas [Os-4(CO)(12)M-2 (eta(6)-C6H6)(2)] (M=Os, Ru) have one M(eta(6)-C6H6) unit in a site connected to three other metals, {3}, and one in a site connected to four other metals, {4}, [Os-4(CO)(12)OsRu(eta(6)-C6H6)(2)] has the Ru(eta(6)-C6H6) unit in the {3} site irrespective of whether the Os or Ru anion is capped. Coupling of these anions with Au(2)dppm yields [Os4M(CO)(12)(eta(6)-C6H6)(Au(2)dppm)] (M = Os, Ru), which have the arene ligand in the axial site of a trigonal bipyramid and the digold unit capping two faces. Reduction of[H2Os5(CO)(15)] with K/Ph2CO and coupling with [Ru(eta(5)-C5H5)(MeCN)(3)](2+) yields the monoanion [Os-5(CO)(15)Ru(eta(5)-C5H5)](-) which reacts with [AuPPh3](+) generating [Os-5(CO)(15)Ru(eta(5)-C5H5)(AuPPh3)] with the "Ru(C5H5)" unit in the terminal {3} site.