Reactivity of [Os3(CO)10(NCMe)2] and [Os3(CO)10(?-Cl)(?-AuPPh3)] with 4-mercaptopyridine: X-ray structure of [Os3(CO)10(?-H)(?-SC5H4N)] and [Os3(CO)10(?-AuPPh3)(?-SC5H4N)]

The compound [Os3(CO)10(?-Cl)(?-AuPPh3)] (2) was prepared from the reaction between [Os3(CO)10(NCMe)2] (1) and [AuClPPh3] under mild conditions. The reaction of 2 with 4-mercaptopyridine (4-pyS) ligand yielded compounds [Os3(CO)10(?-H)(?-SC5H4N)] (4), formed by isolobal replacement of the fragment [AuPPh3]+ by H+ and [Os3(CO)10(?-AuPPh3)(?-SC5H4N)] (5). [Os3(CO)10(?-H)(?-SC5H4N)] (4) was also obtained by substitution of two acetonitrile ligands in the activated cluster 1 by 4-pyS, at room temperature in dichloromethane. Compounds 25 were characterized spectroscopically and the molecular structures of 4 and 5 in the solid state were obtained by single crystal X-ray diffraction studies.