Isonitrile substitution reactions of Co4(μ4-SiR)2(CO)11 clusters and the structure of Co4(μ4-SiC6H4OMe)2(CO)7(XyNC)4

The substitution of carbonyl ligands by isonitriles on Co4(μ4-SiC6H4R)2(CO)11 (R=H, OMe, NMe2) clusters has been examined. The reactions could be monitored by electrospray ionisation mass spectrometry, identifying the substituted products as either protonated [M+H]+ (R=NMe2) or oxidised [M]+ (R=H, OMe) ions. Evidence for substitution of up to nine carbonyl ligands was found and the structure of tetra-substituted example, Co4(μ4-SiC6H4OMe)2(CO)7(XyNC)4, was determined.