Synthesis and Selective Recognition of Dihydrogen Phosphate by Urea-Anthraquinone

Abstract

A neutral ligand is synthesized and studied for the binding properties with anions by electrochemical methods. The binding of 1,8-bis[(N'-phenylureido)ethyloxy]anthraquinone (BPUA) with H2PO 4- makes cathodic shift of its electrochemical potentials and red shift of absorption band. This novel neutral anion receptor BPUA binds anions through hydrogen bonding and show high selectivity with H 2PO4- over CH3CO2-, Cl-, and HSO4-. The selectivity of H2PO4- over CH3CO 2-, Cl-, and HSO4- may be attributed to the stronger hydrogen bonding with urea moiety and also with anthraquinone moiety of BPUA receptor, and also the higher complementarity of the cavity of BPUA for tetrahedral H2PO4-.