Synthesis and characterization of methylbismuth(III) complexes containing dithio ligands: crystal and molecular structure of MeBi{S2COMe}(2) and transformation of MeBi{(S2COPr)-Pr-i}2 to Bi2S3

Reactions of sodium/potassium salts of xanthates, dithiocarbamates and dialkyldithiophosphates with methylbismuth dichloride have been carried out in 1:2 stiochiometric ratio in anhydrous benzene and products of the type [MeBi(S2COR)(2)] (R = Me, Et, Pr-i), [MeBi(S2CNR2)(2)] (R = Me, Et, 1/2C(4)H(8)N) and [MeBi{S2P(OR)(2)}(2)] (R = Me, Et, Pr-i) have been isolated. All of these complexes were characterized by elemental analyses and by IR and NMR (H-1, C-13 and P-31) spectra. The X-ray structure of [MeBi(S2COMe)(2)] indicates that the immediate environment around the central bismuth atom is distorted square pyramidal. However, inclusion of a significant Bi...S intermolecular bond results in pentagonal pyramidal geometry. Thermolysis of [MeBi((S2COPr)-Pr-i)(2)] in xylene indicates that it is a good precursor for preparation of Bi2S3 at low temperature