Synthesis and characterization of organotin (IV) complexes; monoalkyltin (IV) pyridinecarboxylates

Reactions of monoalkyltin(IV) trichloride with sodium salts of pyridinecarboxylic acid in 1:3 stoichiometry yields complexes of the type RSn(O2CPy)(3) (R=PhCH2 , 4-ClC6H4CH2, Py=2-pyridinyl, 3-pyridinyl, 4-pyridinyl). These complexes have been characterized by elemental analyses: IR and H-1, 13 C and Sn-119 NMR spectroscopy. The crystal structure of monobenzyltin(IV) 2-pyridinecarboxylate has been determined by single crystal X-ray diffraction. In this complex, the tin atoms are rendered seven-coordinate in a distorted pentagonal bipyramidal geometry, surrounded axially by the one oxygen atom from the carboxylate ligand and one a-carbon atom of the benzyl group and equatorial by the three oxygen atoms from the carboxylate ligand and two nitrogen atoms of pyridine groups.