Cluster Fragmentation and Facile Cleavage of Phenyl Groups from the SnPh3Ligand in Reactions of Os3(CO)11(SnPh3)(μ-H) with CO and HSnPh3

Abstract

Two new cluster complexes, Os3(CO)12(Ph)(μ3-SnPh), 8 (35% yield), and Os4(CO)16(μ4-Sn), 9 (10% yield), were formed when the complex Os3(CO)11(SnPh3)(μ-H), 6, was heated to reflux in toluene solvent under a CO atmosphere. Compound 8 was transformed to 9 in 28% yield when a solution in octane solvent was heated to reflux under a CO atmosphere. Biphenyl was a coproduct in this reaction. Compound 8 contains three osmium atoms with a triply bridging SnPh group. The triosmium cluster has opened and there is only one Os−Os bond between the three osmium atoms. Compound 9 contains two Os2(CO)8 groups held together by a central quadruply bridging tin atom, giving an overall bow-tie structure for the five metal atoms. Two other new compounds, Os2(CO)6(μ-SnPh2)2(SnPh3)2, 10, and HOs(CO)4(SnPh3), 11, were formed in 51% and 20% yields, respectively, from the reaction of 6 with HSnPh3. Compound 10 contains only two osmium atoms linked by an Os−Os bond and two bridging SnPh2 ligands. Each osmium atom also contains one te...