Organotin esters of 3-benzoylpropionic acid. Crystal structure of triphenyltin(IV) 3-benzoylpropionate, (C6H5)3SnOC(O)(CH2)2C(O)C6H5

Abstract Tin-119 m Mossbauer (80 K) and solution carbon-13 NMR spectra are reported for six organotin 3-benzoylpropionates, R n Sn[OC(O)(CH 2 ) 2 C(O)C 6 H 5 ] 4- n ( n = 2, R = CH 3 , n-C 3 H 7 , n-C 4 H 9 ; n = 3, R = CH 3 , n-C 4 H 9 , C 6 H 5 ). The diorganotin bis-3-benzoylpropionates adopt trans -C 2 SnO 4 octahedral geometries and the triorganotin 3-benzoylpropionates trans -C 3 SnO 2 trigonal bipyramidal geometries in the solid state, but the coordination numbers are lower in solution. From the variable-temperature Mossbauer decay coefficient, a rigid polymeric structure was predicted for the triphenyltin ester, and this configuration was confirmed by an X-ray diffraction study at 296 K. Molecules of triphenyltin 3-benzoylpropionate (space group P 2 1 / n with a 12.881(2), b 11.384(2), c 17.080(2) A, β 104.06(2)°; Z = 4) are carboxylate-bridged into a polymeric chain; the ketonic oxygen is not involved in coordination.