Tin(IV) complexes with O-ethyl(N-ethyl-N,N-dimethylammoniomethyl)phosphonate

O, O -Diethyl-(N,N-dimethylaminomethyl)phosphonate undergoes ethyl migratio n leading to O-ethyl-(N-ethyl-N,N-dimethylammoniomethyl)phosphonate (L). Se veral new complexes of tin(IV) and organotin(IV) chlorides with the title l igand have been synthesized. The stoichiometry of the obtained complexes is as follows: (R3SnCl)(2) L (R = Me, Bu, Ph), R2SnCl2 L (R = Me, Bu, Ph), RS nCl3 L (R = Me, Ph) and SnCl4 L. All the complexes have been studied in sol ution by means of H-1-, C-13-, P-31- and Sn-119-NMR spectroscopy. Their sol id state structures have been investigated by means of Mossbauer spectrosco py and the molecular structure of the complex (Ph3SnCl)(2) L has been deter mined by X-ray crystallography. The ligand behaves as a bidentate ligand, b ridging two pentacoordinate trigonal bipyramidal organotin moieties through an O-P-O fragment. The spectroscopic data for R2SnCl3 L, RSnCl3 L and SnCl 4 L suggest hexacoordinate structures with an octahedral tin environment, t he complexes probably being polymeric according to the bridging ligand beha vior. (C) 1999 Elsevier Science S.A. All rights reserved.