反应详情

Ethyl acetate (1250 ml) was cooled to 5° C., and (1S,4S,5S)-4-bromo-6-oxabicyclo[3.2.1]octan-7-one (250 g) was then added thereto. Thereafter, a 50% dimethylamine aqueous solution (382 ml) was added to the above obtained solution, and the obtained mixture was then stirred for 14 hours. Thereafter, citric acid (234.2 g), 20% saline (500 ml), and ethyl acetate (625 ml) were added to the reaction mixture, and the obtained mixture was then stirred for 30 minutes, so that the organic layer was separated. Further, the aqueous layer was extracted with ethyl acetate (1875 ml). The organic layers were gathered, and the gathered organic layer was then concentrated to 1250 ml. Thereafter, water (500 ml) was added to the concentrated solution, and the mixed solution was then concentrated again to obtain the title compound (274.5 g, yield: 90%) in the form of an aqueous solution (625 ml).

1. stirringthe obtained mixture was then stirred for 30 minutes, so that the organic layer
2. customwas separated
3. extractionFurther, the aqueous layer was extracted with ethyl acetate (1875 ml)
4. concentrationthe gathered organic layer was then concentrated to 1250 ml
5. additionThereafter, water (500 ml) was added to the concentrated solution
6. concentrationthe mixed solution was then concentrated again