Phase Transfer Catalytic Preparation of the Dipolar Aprotic Solvents DMI and DMPU

Abstract The title compounds are prepared by methylation of the respective cyclic ureas using Me2SO4/catalyst/powdered NaOH (for DMI) or K2CO3 (for DMPU). Improved procedures are communicated for the preparation of 2-imidazolidine and trimethylene urea.