反应详情

204.0 g of 3-benzyloxy-1-chloro-2-propanol, 660 ml of hexane, 626.3 g of methoxymethyl propionate and 5.79 g of p-toluenesulfonic acid mono-hydrate were placed into a 2-liter 3-neck round bottom flask equipped with a thermometer, mechanical stirrer, nitrogen inlet and an efficient distillation column. The reaction mixture was heated to reflux. The distillate was taken off at about 10:1 to 15:1 reflux ratio keeping the head temperature below 60° C. Samples were taken to monitor the progress of the reaction. The reaction was quenched when the desired level of methyl acetal was reached which is usually less than about 4% methyl acetal. The quench was carried out by rapidly adding a solution of 11.55 g of sodium carbonate in 310 ml of water directly to the hot reaction mixture. The aqueous layer was washed with additional water and/or base to remove any residual propionic acid. The volatiles were removed to leave the crude product as a mobile liquid. Yield: 285.2 g, (97.8%); 92.6% pure..

1. customequipped with a thermometer, mechanical stirrer, nitrogen inlet
2. distillationan efficient distillation column
3. temperatureThe reaction mixture was heated to reflux
4. temperaturereflux ratio
5. customthe head temperature below 60° C
6. customthe progress of the reaction
7. customThe reaction was quenched when the desired level of methyl acetal
8. additionby rapidly adding a solution of 11.55 g of sodium carbonate in 310 ml of water directly to the hot reaction mixture
9. washThe aqueous layer was washed with additional water and/or base
10. customto remove any residual propionic acid
11. customThe volatiles were removed