Synthesis and Protonation of the Dithioformato Complex OsH(.eta.2-S2CH)(CO)(PiPr3)2

The reaction of the complex OsHCl(CO)-(PiPr¡)2 (1) with nBuLi in hexane affords OsHXrfCH.2=CHEt)(CO)(PiPra)2 (2) which reacts with CS2 to give OsH(rf-S2CH)(CO)(PiPr3)2 (3). The reaction of 3 with HBFfOEt2 leads to two different derivatives depending upon the nature of the solvent used. The dihydrogen compound [Os(rf-S2CH)(rf-H¿(CO)(PiPra)2¡-BF4 (4) is formed in dichloromethane-d2, while the methanedithiolate complex [OsH(rf-S2CH2>(COXPiPr3)2]-BF4 (5) is obtained in diethyl ether.