THE CRYSTAL-STRUCTURE OF THE SALTS [HTHIAMINE] [SNME(2)(H2O)CL-3]CL AND [HTHIAMINE][SNPH(2)CL(4)]H2O - COMPETITION BETWEEN WATER AND CHLORIDE FOR COORDINATION TO DIORGANOTIN DIHALIDES

Reaction of thiamine chloride hydrochloride (TCl . HCl) (vitamin B-1 h ydrochloride) with SnMe(2)Cl(2) and SnPh(2)Cl(2) in 9:1 v/v ethanol-wa ter afforded the salts (HT)[SnMe(2)(H2O)Cl-3]Cl (I) and (HT)[SnPh(2)Cl (4)]H2O (II) respectively. Both compounds were characterized by mass s pectrometry and by IR and Raman spectroscopy, and the crystal structur es of both were determined by X-ray diffraction. I crystallizes in the monoclinic space group P2(1)/n; the thiaminium cation adopts the F co nformation, and in the anion the tin atom co-ordinates to two trans C atoms of methyl groups, three Cl atoms and the O atom of a water molec ule in a distorted octahedral arrangement. II crystallizes in the tric linic space group P (1) over bar; the thiaminium cation adopts the S c onformation, and there are two kinds of [SnPh(2)Cl(4)](2-) anion, one placed between two cations with its phenyl groups stacking over their pyridine rings, and the other without a close relationship with any ca tion. The two Sn atoms lie on a crystallographic inversion centre and have a separation of (0.5, 0.5, 0.0). Several hydrogen bonds are prese nt in both structures, as well as S ... O electrostatic interactions i n II.