Reactions of 2-mercaptobenzoic acid with divalent alkaline earth metal ions: synthesis, spectral studies, and single-crystal X-ray structures of calcium, strontium, and barium complexes of 2,2'-dithiobis(benzoic acid)

Murugavel, Ramaswamy ; Baheti, Kanhayalal ; Anantharaman, Ganapathi (2001) Reactions of 2-mercaptobenzoic acid with divalent alkaline earth metal ions: synthesis, spectral studies, and single-crystal X-ray structures of calcium, strontium, and barium complexes of 2,2'-dithiobis(benzoic acid) Inorganic Chemistry, 40 (27). pp. 6870-6878. ISSN 0020-1669

Full text not available from this repository.

Official URL: http://pubs.acs.org/doi/abs/10.1021/ic010519b

Related URL: http://dx.doi.org/10.1021/om00011a054

Abstract

The treatment of MCl2·nH2O (M = Ca, Sr, or Ba) with 2-mercaptobenzoic acid (H-2-MBA) in a 1:2 ratio in an EtOH/H2O/NH3 mixture leads to the formation of extended polymeric solids [{Ca(OOCC6H4SSC6H4COO)(H2O)2}·0.5(C2H5OH)]n (1), [{Sr(OOCC6H4SSC6H4COO)(H2O)2}·0.5(C2H5OH)]n (2), and [{Ba2(OOCC6H4SSC6H4COO)2(H2O)2}·0.5H2O]n (3), respectively. In all of the cases, under the reaction conditions employed, the H-2-MBA ligand undergoes thiol oxidation to form 2,2'-dithiobis(benzoic acid) (H2-DTBB). While the DTBB forms a 1:1 complex with heavier alkaline earth metals (1-3), only an ammonium salt, [(HOOCC6H4SSC6H4COOH)(HOOCC6H4SSC6H4COONH4)] (4), was obtained as the final product in the reaction of H-2-MBA with MgCl2·6H2O. Compounds 1-4 have been characterized with the aid of elemental analysis, thermal analysis, and infrared spectroscopic studies. All of the products are found to be thermally stable and do not melt on heating to 250 °C. Thermogravimetry on complexes 1-3 indicates the loss of coordinated and lattice water/solvent molecules below 200 °C (for complex 2) or 350 °C (for complexes 1 and 3). The solid-state structures of all of the derivatives 1-4 have been established by single-crystal X-ray diffraction studies. The calcium and strontium coordination polymers 1 and 2 are isomorphous. The DTBB ligands in 1 and 2 are hexadentate, and the compounds have a channel structure in which solvent ethanol molecules are included. In compound 3, barium ion forms a complex 3-dimensional coordination polymer where both the carboxylate and the sulfur centers of the DTBB ligands (which are hepta- and octadentate) coordinate to the metal.

Item Type:Article
Source:Copyright of this article belongs to American Chemical Society.
ID Code:30383
Deposited On:22 Dec 2010 10:43
Last Modified:22 Dec 2010 10:43

Repository Staff Only: item control page