反应详情

To a mixture comprising 6.6 g (0.05 mol) of isopropylideneglycerol, 5.9 g (0.03 mol) of trichloromethyl chloroformate and 50 ml of toluene was slowly added dropwise 7.3 g (0.06 mol) of N,N-dimethylaniline dissolved in 20 ml of toluene. After stirring at room temperature for 4 hours, the reaction mixture was poured into diluted hydrochloric acid, extracted with ethyl acetate, washed with water, and dried over magnesium sulfate. After distilling off the solvent, 10.4 g of 2,2-dimethyl-1,3-dioxolan-4-ylmethyl chloroformate was obtained as a colorless liquid. This product showed a single spot in thin layer chromatography (silica gel, benzene: ethyl acetate=10:3) and was satisfactory in NMR data [(60 MHz, CDCl3) α; 1.25, 1.30 (s×2, 6H), 3.1-3.7 (m, 4H), 3.8-4.1 (m, 2H), 3.6 (s, 1H, disappeared by adding D2O)]. Thus it was not purified but directly used in the subsequent step.

1. extractionextracted with ethyl acetate
2. washwashed with water
3. dry with materialdried over magnesium sulfate
4. distillationAfter distilling off the solvent