Catalysis and autocatalysis in urea methanolysis with formation of O-methyl carbamate: A DFT study

Abstract

The complex nature of methanolysis of urea with the formation of O-methylcarbamate was studied using B3LYP/6-311++G(df,p) and M06/6-311++G(df,p) density functional methods. The first stage of the reaction, the decomposition of urea to isocyanic acid and ammonia, proceeds with catalysis by alcohol molecules. In the second stage, the interaction of isocyanic acid with methanol with the formation of O-methyl carbamate, the methanol monomer exhibits low activity. The methanol dimer is significantly more active. The main route for the formation of O-methyl carbamate is the reaction of isocyanic acid with methanol catalyzed by the carbamate itself.