Binuclear Oxidative Addition of Sb–Cl Bonds: A Facile Synthetic Route to Main Group–Transition Element Clusters and Rings

Binuclear oxidative addition of Sb–Cl
bonds with the clusters
Os3(CO)11(NCCH3), 1,
or Os3(CO)10(NCCH3)2, 2, was found to be an effective synthetic route to organometallic
clusters and rings containing μ2-SbPh2 or μ3-SbPh moieties. Thus, the reaction of SbPh2Cl with 1 afforded the tetranuclear ring Os3(CO)11(Cl)­(μ-SbPh2), 3, while its reaction with 2 afforded the pentanuclear
ring Os3(CO)10(Cl)2(μ-SbPh2)2, 6. In each case, two or three
isomeric products were isolated depending on the reaction conditions.
The analogous reaction of SbPhCl2 with 1,
on the other hand, afforded the spiked triangular cluster Os3(CO)11(Cl)2(μ3-SbPh), 7, which also existed as two isomers. Pathways for these reactions
have been proposed, and the experimental and computational evidence
presented.