TRIMETHYLTIN(IV) NAPHTHOATES - X-RAY STRUCTURE OF THE 2-ISOMER

The isomeric trimethyltin(IV) 1- and 2-naphthoates have been prepared in high yield from trimethyltin chloride and the appropriate sodium na phthoate in THF solution. Spectroscopic data for the compounds point t o the presence of monomers, probably with a tetrahedral structure in C DCl3 solution, but five-coordinate trigonal bipyramidal units in the d onor solvent DMSO. An X-ray structure of the 2-isomer shows an infinit e zig-zag chain structure in which the carboxylate group bridges asymm etrically between pairs of tin atoms, which have distorted trigonal bi pyramidal geometry. Much of the distortion can be traced to a weak res idual chelating effect from the carboxylate group.