SYNTHESIS OF COMPLEXES OF DIMETHYLTIN(IV) WITH MONO-DEPROTONATED AND DI-DEPROTONATED PYRIDOXINE (PN) IN MEDIA WITH VARIOUS ANIONS - CRYSTAL-STRUCTURES OF [SNME2(PN-H)]NO3-CENTER-DOT-2H(2)O, [SNME2(H2O)(PN-H)]-CL-CENTER-DOT-H2O AND [SNME2(H2O)(PN-2H)]CENTER-DOT-0.5H(2)O

The reaction of the dimethyltin(IV) cation with pyridoxine [3-hydroxy- 4,5-bis(hydroxymethyl)-2-meth PN] has been investigated in ethanol-wat er (80:20 v/v) containing NO3- and Cl-, NO3- and MeCO2- or Cl- and MeC O2- ions in various mole ratios. The compounds [SnMe2(PN-H)]NO3 . 2H(2 )O 1, [SnMe2(H2O)(PN-H)]- H2O 2 and [SnMe2(H2O)(PN-2H)]. 0.5H(2)O 3 we re isolated and characterized by-IR, Raman, cross polarization magic a ngle spinning C-13 NMR and electron impact andFAB mass spectrometry. T he structures of the compounds were determined by X-ray diffraction. I n I [SnMe2(PN-H)](2)(2+) units in which each moho-deprotonated pyridox ine co-ordinates to one tin atom via the phenolic O and a deprotonated CH2OH group O and to the other via the latter group alone are connect ed in a polymeric structure via the other CH2OH group of each PN-H. In each dimeric unit the tin atom is co-ordinated to two methyl groups, the phenolic O atom, the O atoms of two deprotonated CH2OH groups, and the O atom of a non-deprotonated CH2OH group. Hydrogen-bonded water a nd NO3- ions are also present in the crystal lattice. In 2 the lattice contains dimeric [SnMe2(H3O)-(PN -H)](2)(2+) units (in which the tin- pyridoxine co-ordination is the same as:in 1 except that the bonds con necting different units in 1 now bind aqua ligands) and hydrogen-bonde d water and chloride ions. In 3 the crystal contains dimeric [SnMe2(H2 O)(PN-2H)](2) units (in which the dideprotonated ligand co-ordinates a s in 2) and water. The behaviour of these compounds in D2O and (CD3)(2 )SO was studied by NMR spectroscopy.