Hydrolytic degradation of 2,6-dichlorobenzylthiopseudourea hydrochloride

Degradation of 2,6-dichlorobenzylthiopseudourea hydrochloride was followed in basic medium (pH 7.5) to isolate and characterize all possible degradation products. IR, Raman, and NMR spectroscopy, TLC, and elemental analysis were used to identify the products. Degradation of base-hydrolyzed 2,6-dichlorobenzylthiopseudourea hydrochloride produced 2,6-dichlorobenzylthiol and cyanamide and was followed by oxidation (air) to produce bis(2,6-dichlorobenzyl) disulfide, dimerization to give cyanoguanidine, and hydrolysis to yield urea. The kinetics of hydrolysis at 22.5 degrees (pH 7.0 and 7.5) and at 37 degrees (pH 7.0) revealed a pseudo-first-order reaction with respect to the substrate. Apparent first-order rate constants and energy of activation, entropy of activation, and half-life values were determined.