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Published on: December 12, 2017
Anion Binding Studies of Urea and Thiourea Functionalized Molecular Clefts
Utsab Manna1, Bobby Portis1, Tochukwu K Egboluche1
1Department of Chemistry, Physics and Atmospheric Sciences, Jackson State University, Jackson, MS, United States.
Abstract:
Two rationally designed 4-nitrophenyl-based molecular clefts functionalized with thiourea (L ) and urea (L ) have been synthesized and studied for a variety of anions by UV-Vis and colorimetric techniques in DMSO. Results from the binding studies suggest that both L and L bind halides showing the order: fluoride > chloride > bromide > iodide; and oxoanions showing the order: dihydrogen phosphate > hydrogen sulfate > nitrate > perchlorate. Each receptor has been shown to form a 1:1 complex with an anion via hydrogen bonding interactions, displaying distinct color change for fluoride and dihydrogen phosphate in solution. As compared to the urea-based receptor L , the thiourea-based receptor L exhibits stronger affinity for anions due the presence of more acidic thiourea functional groups.
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