Stoichiometric reaction and catalytic effect of 2-dimethylaminoethanol in urethane formation.

A computational study of the stoichiometric reaction and catalytic effect of 2-dimethylaminoethanol (DMEA) in urethane formation was performed. DMEA, besides its catalytic tertiary amine site, contains a hydroxyl group that can react with isocyanates and thus, it can affect the synthesis of polyurethane. In the catalytic system, the reaction between phenyl isocyanate and butan-1-ol, involving DMEA as a catalyst, was investigated. Meanwhile, for the competitive stoichiometric process, the reaction between phenyl isocyanate and DMEA was also considered. Both reactions were investigated by using the G3MP2BHandHLYP composite method and acetonitrile was chosen as the solvent. It was revealed that both pathways (catalytic and stoichiometric processes) are similar thermodynamically, but the catalytic reaction is preferred kinetically, which indicates the applicability of DMEA in urethane synthesis.