Catalysis by hydrogen halides in the gas phase. Part XXVI. Isopropylamine and hydrogen bromide

Abstract

The hydrogen bromide catalysed deamination of isopropylamine between 435 and 490 °C is described. Propene and ammonia are the major products of the decomposition. The reaction is believed to be homogenous, first order in both the acid and the substrate, and is molecular. The rate constant is expressed by the equation: k₂= 10^12·41 exp (–33,115/RT) cm³ mol^–1 s^–1(where R= 1·987 cal mol^–1; 1 cal = 4·187 J). A relatively smaller effect of α-methyl substitution in the hydrogen bromide catalysed deamination of amines as compared with that observed in the catalysed dehydration of alcohols is explained in terms of the greater basicity of amines.