SYNTHESIS AND CHARACTERIZATION OF DIORGANOTIN(IV) DERIVATIVES OF 2-MERCAPTOPYRIDINE AND CRYSTAL-STRUCTURE OF DIPHENYL PYRIDINE-2-THIOLATOCHLOROTIN(IV)

Diorganotin(IV) derivatives of 2-mercaptopyridine (HSPy), R2Sn(SPY)2, R2SnCl(SPy) (R = Me, iPr, nBu, tBu, Cy, Ph) and Cy2SnBr(SPy), were obt ained from R2SnX2 (X = Cl, Br) and NaSPy. Ph2SnCl(SPy) crystals, as de termined by single-crystal X-ray diffraction, are monoclinic in the sp ace group P2(1)/n. Tin forms with the bidentate SPy ligand a four-memb ered chelate ring with a short NSnS bite angle of 64.8(1)-degrees lead ing to a heavily distorted trigonal-bipyramidal environment about tin. Apical Cl-Sn-N angle = 156.1(1)-degrees; equatorial C-Sn-C angle = 12 1.9(2)-degrees. From Sn-119 Mossbauer and IR data, analogous structure s are inferred for the other solid compounds R2SnX(SPy), and distorted octahedral molecular structures for the solid compounds R2Sn(SPy)2 wi th R in the trans position, and sulfur atoms and nitrogen-donor atoms each in cis positions. According to IR and H-1, C-13 and Sn-119 NMR da ta, the solid-state molecular structures are retained in chloroform so lution.