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The reaction of 2-mercapto-benzoic acid (H2MBA), 2-mercato-nicotinic acid (H2MNA), and 2-mercapto-pyrimidine (PMTH) with a twofold molar amount of di-iodine (I2) results in the isolation of crystals of the neutral disulfides of formulae: {(HMBA)2·1/2(CH3CN)} ( 1), {(HMNA)2·(H2O)} ( 2), and (PMT)2 ( 3), respectively, when dichloromethane/acetonitrile/methanol ( 1) or dichloromethane ( 2,3) were used as solvents. The reaction of di-iodine with thethiol PMTH and 2-mercapto-benzothiazole (MBZTH) yields the disulfide (PMT)2 ( 3), and the di-iodine adduct of formula {[MBZTH-I2]·[MBZTH]2} ( 4), respectively. The reaction of di-iodine with 5-nitro-2-mercapto-benzimidazole (O2N-MBZIMH) ( 5) in the presence of ferric trichloride hydrate (FeCl3·6H2O), in a 6:3:1 (I2:thiol:FeCl3·6H2O) molar ratio, results in cocrystal ( 6), which contain the desulfurated hydroxyl derivative O2N-BZIMOH ( 6a) and unreacted O2N-MBZIMH ( 6b) in a 3:1 molar ratio. The compounds were characterized by elemental analysis, FT-IR, and 1H NMR spectroscopy. The crystal structures of compounds 1- 6 were also determined by X-ray crystallography. Cyclic voltammetry measurements showed that thiols with low oxidation potentials (< 1.0 V) mainly form disulfides upon a reaction with di-iodine, whereas those with higher oxidation potential form charge transfer (CT), resulting in desulfurated products, MBZIMH. However, in the case of O2N-MBZIMH a desulfurated species was isolated. The formation of the final product also requires the presence of FeCl3. © 2012 Wiley Periodicals, Inc. Heteroatom Chem 23:498-511, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/hc.21042 [ABSTRACT FROM AUTHOR]

The reactions of tetrachloroauric(III) acid (HAuCl4) with the thioamides; 2-mercapto-benzothiazole (mbztH) and 5-ethoxy-2-mercapto-benzimidazole (EtmbzimH) lead to the desulfuration of the ligands and the formation of the ionic complexes {[AuCl4]−[bztH2]+} (1), and {[AuCl4]−[EtbzimH2]+(H2O)} (2) (where bztH2+and EtbzimH2+are the desulfurated cations of the starting ligands). The reaction of HAuCl4with 2-mercapto-nicotinic acid (mnaH2), however results in the formation of 2-sulfonate-nicotininc acid (C6H5NO5S) (3) with the simultaneous oxidation of the sulfur atom. On the other hand, the reactions of the gold(I) complex [Au(tpp)Cl] (4) (tpp = triphenylphosphine (Ph3P)) with the thioamides; 2-mercapto-thiazolidine (mtzdH), 2-mercapto-benzothiazole (mbztH) and 5-chloro-2-mercapto-benzothiazole (ClmbztH) in the presence of potassium hydroxide resulted in the formation of the gold(I) complexes of formulae [Au(tpp)(mtzd)] (5), [Au(tpp)(mbzt)] (6) and [Au(tpp)(Clmbzt)] (7) without ligand desulfuration. All complexes have been characterized by elemental analysis, FT-IR, far-FT-IR,1H-NMR, spectroscopic techniques and X-Ray crystallography. The electrochemical behavior of 1, 2and 4-7complexes and the ligands EtmbzimH, mbztH and mnaH2was also studied in acetonitrile and DMF using cyclic voltammetry. The results are in support of a mechanism of desulfuration of the ligands by Au(III), involving a first oxidation of S to -SO3−, followed by a C-S bond cleavage. This is also supported by PM6 calculations of bond dissociation energies of the various compounds involved. Complexes 1, 2and 4-7were tested for in vitrocytotoxicity against leiomyosarcoma cells and the results are discussed in relation with the geometry of the complexes and compared with those of cisplatin and other metals. Complexes 1and 5showed higher activity than that of cisplatin, while HAuCl4was inactive against sarcoma cells. [ABSTRACT FROM AUTHOR]

Studies the crystal structure of cadmium tetrahydrate, a polymer with metal-organic chains stacked along the a axis forming layers parallel to the ab plane. Crystal growth; Hydrogen-bonded network formed by the water molecules and the carboxylate oxygen atoms.