Triosmium clusters with bridging terpenic thioureato-like ligands

The reaction of acetone-4-(2-methoxy-phenyl)thiosemicarbazone with triosmium cluster Os3(CO)11(NCMe) results in the formation of the cluster with the μ2 chelate-bridging ligand coordinated by S and N1 atoms, which was studied by X-ray diffraction analysis. Reaction of (3aR, 3bR, 4aR, 5aS)-5a-hydroxy-3,4,4-trimethyl-3a,3b,4,4a,5,5a-hexahydrocyclopropa[3, 4]cyclopenta[1,2-c]pyrazole-1-carbothioic acid amide with Os3(CO)11(NCMe) gives rise to the complex with the bridging ligand coordinated by sulphur atom. Further transformation of the complex in hot benzene results in tautomeric rearrangement of the organic ligand and the cleavage of the pyrazolinol cycle to form an open chain tautomer. Unusual silica gel induced oxidative cleavage of the cyclopropane ring in the open chain derivative and epoxidation of cycloalcane C–C bond are observed on the air.