It was found that N,N,N′,N′-tetramethylmethylenediamine reacted with a number of dihalides to form the corresponding cyclic quaternary ammonium compound and dimethylamine hydrohalide. The process involves a Menschutkin reaction with fragmentation of N,N-dimethylmethyleneamine followed by a second Menschutkin reaction to form a cyclic compound. The reaction proceeds best in a polar solvent and the yields are moderate to good.