Synthesis of Two Novel Aroyl Thioureas and Their Use as Anion Binding Receptors

Abstract

New aroyl thioureas; N-nicotinoyl-N'-(4-nitrophenyl) thiourea (3a) and N-nicotinoyl-N'-(2-nitrophenyl) thiourea (3b) were synthesized and studied as anion-binding receptors. Upon adding tetrabutyl ammonium halides (fluoride, chloride bromide and iodide), cyanide and hydroxide ions to their solutions in DMSO respectively, the colour of the solutions has shown striking changes from pale yellow to brillant yellow or red. The binding effects of the anions were investigated by UV-VIS spectroscopic method and H-1 NMR titrations.