Synthesis and characterisation of the carboxylate linked osmium clusters [{Os3H(CO)10}2(CO2CH2CO2)], [{Os3H(CO)10}2(CO2C2H4CO2)], [{Os3H(CO)10}2(C4O4)] and [{Os3H(CO)10}2(C4O4){Co2(CO)6}]

The reaction of 2 equiv. of [Os3(CO)10(NCMe)2] with a series of dicarboxylic acids leads to the formation of a series of hexanuclear linked clusters. The reaction of one of these clusters, [{Os3H(CO)10}2(C4O4)] with [Co2(CO)8] affords the mixed metal cluster [{Os3H(CO)10}2(C4O4){Co2(CO)6}].