Spectroscopic Studies and Structure of 4-(3-Benzoylthioureido)benzoic Acid

Abstract

4-(3-Benzoylthioureido)benzoic acid has been synthesized from the reaction of 4-aminobenzoic acid with benzoyl isothiocyanate. The title compound has been characterized by elemental analysis, MS, FT-IR, 1H-NMR, 13C-NMR and UV–Visible techniques. The structure of the compound has also been examined crystallographically. The title compound crystallizes in the triclinic space group P-1 with a = 3.969(1), b = 13.039(1), c = 13.504(1) A, α = 96.50(1)°, β = 92.25(1)°, γ = 94.94(1), V = 691.0(1) A3 and D x = 1.444 g cm−3, respectively. The crystal structure has been solved by direct methods and refined by full-matrix least squares and found R 1 = 0.031 and wR 2 = 0.081 for 2909 observed reflections [I > 2σ(I)]. Thiourea and its derivatives have been widely used in research and technological applications such as in the pharmaceutical industry, as catalysts in chemical reactions and for extraction of toxic metals using a solid supported liquid membrane system. Furthermore these compounds have been used as ligands in the formation of metal complexes. In these complexes thiourea and its derivatives are coordinated to a metal ion either by the N or S atoms, by both of them or by other donor atoms available in the molecule. It has been shown to exist as tautomeric forms due to intramolecular proton shifts between the thioketo-sulfur and the amine-nitrogen, via intramolecular hydrogen bonding N–H···S or S–H···N.