On the Thermal Dissociation of Organic Compounds. XIV. The Effects of the Solvents and of the Substituents on the Thermal Dissociation of Urethans in Amines

N-phenyl-phenyl carbamates dissociate into their component compounds very readily in the presence of a base. Unlike the case of N-phenyl-alkyl carbamates, N-phenyl-phenyl carbamates dissociate in the presence of an equimolar amount of an amine at lower temperature. The kinetics of the dissociation of N-phenyl-phenyl carbamates were of the first order with respect to carbamates and of the first order with respect to base. The rate constants, the activation energies and the entropies of activation of the dissociation of N-phenyl-phenyl carbamates in various amines and solvents were measured throughout temperature interval 0∼140°C. The effects of amines, solvents and substituents on the dissociation of urethans in amines were studied.