AMMONOLYSIS OF 1,2-EPOXYCYCLOHEXANE AND TRANS-2-BROMOCYCLOHEXANOL

Abstract

Optimum conditions for the preparation of trans-2-aminocyclohexanol by ammonolysis of 1,2-epoxycyclohexane or trans-2-bromocyclohexanol are realized by use of a 20-fold excess of aqueous alcoholic ammonia at 100°. Under these conditions formation of secondary amines is minimized. Lower ammonia–reactant ratios, or the use of absolute methanolic ammonia or aqueous ammonia, lead to lower yields of primary amine and higher yields of secondary amines. 1,2-Epoxycyclohexane has been isolated from the interaction of trans-2-bromocyclohexanol with aqueous ammonia. The oxide reacts more rapidly with aqueous alcoholic ammonia than the bromohydrin and the rate of conversion of the latter to amine is thus controlled by the rate of conversion of bromohydrin to oxide.