Preparation of bis-quaternary ammonium salts from epichlorohydrin

A novel bis-quaternary ammonium salt was prepared conveniently and almost quantitatively from N,N-dimethyldodecylamine, its hydrochloride, and epichlorohydrin. Reaction of N,N-dimethyldodecylamine with epichlorohydrin (in the presence of the amine hydrochloride) or various dichloro compounds was investigated by using H-1 nuclear magnetic resonance. The reaction route was studied by examining the reactivity of reagents with the amine and the effect of reaction temperature. The ease of the reaction with epichlorohydrin was found to be due to the assistance of amine hydrochloride in opening the epoxide ring and to neighboring-group participation by the hydroxyl group of the intermediate mono-ammonium salt in the quaternization step. Neighboring-group participation by the hydroxyl group in these quaternization reactions is also discussed.