A DFT study of structures of dipicolyl urea isomers and their recognition with carboxylic acids and their carboxylate anions

Abstract

Four isomers of dipicolyl urea were obtained and the intramolecular hydrogen‐bonded structure was found to be the most stable isomer. Energetics, thermodynamic properties, rate constants, and association constants of their isomerizations computed using the B3LYP/6‐31+G(p,d) method were obtained. Complexes of all isomers of dipicolyl urea with formic acid, acetic acid, benzoic acid, oxalic acid, and their deprotonated species were investigated. Energetics, thermodynamic properties, and rate constants of their associations were obtained. Stabilities of all complexes in terms of association constants of the most stable species were determined. Copyright © 2010 John Wiley & Sons, Ltd.