Quantum-Chemical Study on the Reaction of Phenyl Isocyanate with Linear Methanol Associates. Addition at the C=N Bond

Quantum-chemical calculations at the B3LYP/6-311++G(df,p) level of theory showed that reactions of phenyl isocyanate with methanol associates involve formation of pre-and post-reaction complexes. The reactions proceed through late asymmetric cyclic transition states. The height of the energy barrier decreases as the degree of association of the alcohol increases. The relative change in the Gibbs energy in the reaction of phenyl isocyanate with methanol also becomes smaller as the degree of alcohol association increases.