Mono
-organotin(IV) and tin(IV) derivatives of 2-mercaptopyridine (HSPy) and 2-mercaptopyrimidine (HSPym), RSnL 3 (R = Me, n-Bu, Ph; L = SPy, SPym; R = Bz = benzyl, o-ClBz, o-ClC 6 H 4 , p-ClC 6 H 4 , o-tolyl, p-tolyl; L = SPy), RSnClL 2 (R = Me, n-Bu, Ph; L = SPy, SPym), RSnCl 2 L (R = Me, n-Bu; L = SPy, SPym) and SnCl 4 Ϫ n L n (L = SPy, SPym; n = 2, 4) were obtained from RSnCl 3 or SnCl 4 and NaL or by neutralization (R = Ph, p-tolyl; L = SPy, SPym). RSnClL 2 and RSnCl 2 L were better prepared by comproportionation of RSnCl 3 and RSnL 3 . MeSn(SPy) 3 and PhSn(SPy) 3 • 1.5CHCl 3 crystals, as determined by single-crystal X-ray diffraction, are monoclinic. In the discrete monomeric RSn(SPy) 3 units, three bidentate SPy ligands together with R form a distorted pentagonal bipyramid around tin. One S and the C(R) atom are in the axial positions. Two S atoms and three N atoms form the pentagonal plane. From 119 Sn Mössbauer and IR data, analogous structures are inferred for the other solid RSnL 3 compounds, except for R = Bz, o-ClBz, o-ClC 6 H 4 and o-tolyl, in which tin would be hexacoordinated. In the compounds RSnClL 2 and RSnCl 2 L, tin is at the center of an octahedron or a trigonal bipyramid, respectively. For Sn(SPym) 4 and SnCl 2 (SPym) 2 , the same type of octahedral structure as was previously found for Sn(SPy) 4 • HSPy and SnCl 2 (SPy) 2 is proposed.
According to IR and 1 H, 13 C and 119 Sn NMR data, the solid-state molecular structures are retained in chloroform and dimethyl sulfoxide solution.