Synthesis and structural characterization of diorganotin(IV) esters of salicylidene-amino acids

Eight diorganotin esters of salicylidene-L-tryptophan(Sal-T) and salicylidene-L-valine(Sal-V), [(n-Bu)2Sn(Sal-T)] (1), [(n-Bu)2Sn(Sal-V)] (2), [Ph2Sn(Sal-T)] (3), [Ph2Sn(Sal-V)] (4), [(PhCH2)2Sn(Sal-T)] (5), [(PhCH2)2Sn(Sal-V)] (6), [(4-ClC6H4CH2)2Sn(Sal-T)] (7) and [(4-ClC6H4CH2)2Sn(Sal-V)] (8) have been synthesized and characterized by elemental analysis, IR and 1H NMR. The crystal structures of compounds 1 and 2 have been determined by X-ray single crystal diffraction. Their structures show the tin atoms of two compounds are rendered five-coordinated in distorted trigonal bipyramidal geometries.