反应详情

4.10 g (15.2 mM) of (5R)-3-(4-methoxyphenyl)-5-phenyl-2-oxazolidinone synthesized in Example 1 was dissolved in 100 ml of methylene chloride and cooled to -75° to 70° C. on a dry ice-acetone cooling bath. To the solution, 31.5 ml of 1.0M-solution of boron tribromide in methylene chloride was added dropwise in 43 minutes, followed by stirring for 1 hour at -75° to -70° C. and further stirring for 2 hours at room temperature. After the reaction, the reaction mixture was poured into ice water and subjected to extraction with ethyl acetate. The organic layer was washed with water and dried with anhydrous sodium sulfate, followed by evaporation under reduced pressure to obtain a residue. To the residue, an appropriate amount of hexane was added to precipitate a crystal. The crystal was recovered by filtration, thus obtaining 3.13 g of (5R)-3-(4-hydroxyphenyl)-5-phenyl-2-oxazolidinone (Yield: 80.5%).

1. temperaturecooled to -75° to 70° C. on a dry ice-acetone cooling bath
2. stirringfurther stirring for 2 hours at room temperature
3. customAfter the reaction
4. extractionsubjected to extraction with ethyl acetate
5. washThe organic layer was washed with water
6. dry with materialdried with anhydrous sodium sulfate
7. customfollowed by evaporation under reduced pressure
8. customto obtain a residue
9. customto precipitate a crystal
10. filtrationThe crystal was recovered by filtration