DIORGANOTIN HALIDE CARBOXYLATES, THIOCARBOXYLATES AND HALIDE HALOACETATES

Twenty-eight diorganotin halide acetates, thioacetates, haloacetates and carboxylates, eighteen not previously reported, have been synthesized by the reaction between the diorganotin oxides and acid halides, and by transacyloxylation reactions between diorganotin halide acetates and carboxylic acids. Infrared in the 2000-200 cm-1 range, proton and carbon-13 NMR and tin-119m Mössbauer data are interpreted in terms of acetoxy-bridged, trigonal bipyramidal tin in the solid phase with depolymerization occurring in solution where a dynamic equilibrium between diorganotin dihalide and dicarboxylate species is rapidly established. A new infrared absorption also appears at 100-125 cm-1 to higher frequency of the vasym(CO2) which disappears on heating. A dimeric structure based upon four-membered Sn2O2 or Sn2OX rings in which carboxylate group oxygen atoms bridge tin atoms of a second molecule leaving the CO group free is proposed. The halide thioacetates are associated in the solid state but are monomeric in solution. © 1979.