LIGAND-EXCHANGE IN ADDUCTS OF TRIPHENYLTIN FLUORIDE

A F-19 and Sn-119 NMR study of Ph3SnX2- (X = F, Cl) and Ph3SnF:B (B = HMPA, DMSO) has shown that fluorine exchange occurs between four- and five-coordinate tin complexes, presumably via fluorine- and chlorine-bridged intermediates. The results point to a modified view of the isomerization and racemization of triorganoelement halides. Some reactions of Ph3SnF2- with tellurium and phosphorus compounds are described and the synthesis of PhSnF52- reported, but attempts to prepare six-coordinate adducts Ph3SnX32- or Ph3SnX2:B- were unsuccessful, although their presence in solution was indicated by NMR spectroscopy.