STRUCTURAL AND SPECTROSCOPIC STUDIES OF CATION ANION INTERACTIONS IN PENTACOORDINATE ORGANOTIN COMPOUNDS

A series of anionic organotin compounds of the type [Me3SnCl2][M] (M+ = n-Bu4N (3), K(18-crown-6) (4)) and the type [Me3SnCI(X)][M] (M+ = Et4N, X = CN (5); M+ = K(18-crown-6), X = CN (6); M+ = K(18-crown-6), X = F (7)) is described. The ability of a particular cation to interact with its corresponding organotin anion was investigated in the solid state and compared with its behavior m solution. The molecular structures of organotin anions 4 and 6 have been studied by X-ray crystallography. Both compounds exhibit infinite-chain structures of cations and anions in the solid state, in contrast to related organotin anions. Compound 4 crystallized in the monoclinic space group C2/c with a = 12.546 (1) A, b = 17.988 (1) angstrom, c = 17.996 (2) angstrom, beta = 90.266 (2)-degrees, V = 1259 angstrom3, z = 4, and R = 0.064. Compound 6 in the m . c space group P2(1) with a = 7.920 (1) angstrom, b = 21.026 (2) angstrom, c = 7.649 (6) angstrom, beta = 98.762 (2)-degrees, V = 1259 angstrom3, Z = 2, and R = 0.057. The nature of the cation-anion interactions in solution for salts 2-7 was investigated by H-1, C-13, and Sn-119 NMR spectroscopy. Solid-state CP/MAS C-13 and Sn-119 NMR spectra were obtained for compounds 5 and 6. The solution-to-solid chemical shift differences are discussed in terms of the solid-state structures.