S 2CPR 3 adducts as bridging ligands in tricobalt clusters. X-Ray structure of [Co 3(CO) 7(μ 3-CH)(μ-S 2CPCy 3)

Abstract

[Co 3(CO) 9(μ 3-CX)] (X  H, Cl) react with S 2CPR 3 (R  cyclohexyl, Cy or isopropyl, iPr) in CH 2 Cl 2 to give heptacarbonyltricobalt clusters [CO 3(CO) 7(μ 3-CX)(μ 2-S 2CPR 3)] in which the S 2CPR 3 act as four-electron ligands, bridging a CoCo cluster edge in a σ(S), σ(S′) fashion, as shown by an X-ray determination on a crystal of the derivative with X  H, R  Cy. The five-membered CoSCSCo ring is nearly perpendicular to the CO 3 triangle ( i.e. axial), in contrast to the equatorial disposition usually found in related complexes with phosphorus ligands.