Several new mixed ligand diorganotin complexes, [(n-Bu₂SnL¹⁻³)₂SO₄] and [(Me₂Sn)₂(L²)₃(OSO₂Me)] (HL= quinadic acids) have been synthesized and structurally characterized by X-ray crystallography.

Abstract

The synthesis of mixed ligand di-n-butyltin complexes, [(n-Bu₂SnL¹⁻³)₂SO₄], 2–4 (HL¹⁻³=2-quinoline/ 1-isoquinoline/ 4-methoxy-2-quinoline carboxylic acid) has been realized by reacting n-Bu₂Sn(OMe)OSO₂Me, 1 a with the corresponding quinaldic acid under solvothermal conditions. The observed transformation of methane sulfonate to sulfate anion represents a rare example of C−S bond cleavage on the organotin scaffolds, n-Bu₂Sn(L¹⁻³)OSO₂Me, which have been identified as en route intermediates by NMR and X-ray crystallography. Analogous reaction when extended with Me₂Sn(OMe)OSO₂Me, 1 b and HL² yields [(Me₂Sn)₂(L²)₃(OSO₂Me)], 5 as partially disproportionated product of Me₂Sn(L²)OSO₂Me. The solid-state structures of 2–5 reveal variable modes of coordination of the ligands to afford molecular and polymeric motifs.