Syntheses, reactions, and structures of osmium(II) distannyl complexes, LnOs-SnMe2SnR3 (RÂ =Â Me, Ph), from reaction between LnOs-SnClMe2 and either LiSnMe3 or KSnPh3

A simple route to distannyl complexes of osmium, LnOs-SnR2SnR3, involves reaction between complexes with a chloro-substituted stannyl ligand and salts containing tri-organo tin anions. In the 119Sn NMR spectra of these stable osmium(II) distannyl complexes both the α-Sn and β-Sn atoms show well-resolved one-bond 119Sn-119Sn and 119Sn-117Sn coupling. Methyl groups on the α-Sn atoms are readily replaced by halides through reaction with either SnMe2Cl2 or I2 without cleavage of the Sn-Sn bonds.