The title compound, 1,1,2,2-tetracarbonyl-1,2-mu -carbonyl-4,11-dimethylsul
fido-closo-1,2-dicobaltadodecaborane, [Co-2(C4H20B10S2)(CO)(5)], has a clos
o 12-vertex {1,2-Co2B10H8} structure with SMe2 ligands at the exo-4- and 11
-positions. The cluster displays close structural similarities to the SEt2
analogue.