Kinetic Studies of Bimolecular Nucleophilic Substitution. VI. Rates of the Menschtkin Reaction of Methyl Iodide with Methylamines and Ammonia in Aqueous Solutions

Abstract The kinetics of the reactions of trimethylamine, dimethylamine, methylamine, and ammonia with methyl iodide in aqueous solutions have been investigated at temperatures ranging from 0 to 40°C. Kinetic analyses of the consecutive methylations of dimethylamine and methylamine have been conducted according to the method of French. In the case of ammonia a standard second-order kinetic treatment can be successfully used because of the relative sluggishness of the first stage as compared with the succeeding stages. The observed rates are in the sequence: Me3N>Me2NH>MeNH2>NH3. The factors which affect this rate sequence are discussed.