The bimetallic cluster Cp’2Mo2Co2S3(CO)(4) (1) reacts with organic sulfur compounds, e.g. (t)BuSH, Me(2)CHCH(2)CH(2)SH, PhSH, (t)BuNCS, cis-2,3-dimethylthiirane, and thiophene, to give the cubane cluster Cp’2Mo2Co2S4(CO)(2) (2) in high yield. With the thiols, the organic products are the parent hydrocarbons. The thiophene desulfurization products are saturated and unsaturated C-1-C-4 hydrocarbons, and the thiocyanates produce RNC that reacts with 1 and 2 to form the carbonyl substitution products CP’2Mo2Co2S3(CO)3(RNC) and Cp’2Mo2Co2S4(CO)(RNC), respectively. The cis-2,3-dimethylthiirane produces cis-2-butene stereospecifically. The mechanistic implications are, discussed, and the desulfurization reactions are compared to the hydrodesulfurization (HDS) reactions catalyzed by an alumina-supported Mo/Co/S composition.