A new synthesis of carbamic esters from carbon dioxide, epoxides, and amines

Abstract

Carbamic esters may be prepared directly by the reaction of carbon dioxide, epoxides, and primary or secondary aliphatic amines. For example, the monocarbamic ester of the 1,2-diol derived from epoxycyclohexane was obtained in good yield when epoxycyclohexane was reacted with amine in an atmosphere of carbon dioxide. The reaction between an epoxide and a carbamic acid or its ammonium salt, formed from carbon dioxide and amine, is proposed as a reasonable mechanism for the formation of the carbamic ester.