反应详情

温度

-15 °C

A mixture of 2-chloro-6-(2-hydroxyethyl)-4-nitrophenol (11.3 g) and pyridine (41.8 mL) was cooled to −15° C. To this mixture was added dropwise methanesulfonyl chloride (4.04 mL), followed by stirring at −10° C. for 30 minutes. To this reaction mixture was added methanesulfonyl chloride (2.02 mL), followed by stirring at −10° C. for 20 minutes. To the mixture was added a saturated aqueous sodium hydrogen carbonate solution, followed by stirring for 2 hours, the pH was adjusted to 1 with 6 M hydrochloric acid, followed by extraction with ethyl acetate, and the organic layer was washed with saturated brine and then dried over anhydrous sodium sulfate. The insoluble materials were separated by filtration, the filtrate was concentrated under reduced pressure, and then the obtained residue was dissolved in ethyl acetate. To this mixture was added triethylamine (18.1 mL), followed by stirring at 78° C. overnight. After cooling to room temperature, the reaction mixture was concentrated under reduced pressure, and the obtained residue was purified by silica gel column chromatography (hexane:ethyl acetate=100:0 to 70:30) to obtain 7-chloro-5-nitro-2,3-dihydro-1-benzofuran (7.75 g) as a yellow solid.

1. stirringby stirring at −10° C. for 20 minutes
2. stirringby stirring for 2 hours
3. extractionfollowed by extraction with ethyl acetate
4. washthe organic layer was washed with saturated brine
5. dry with materialdried over anhydrous sodium sulfate
6. customThe insoluble materials were separated by filtration
7. concentrationthe filtrate was concentrated under reduced pressure
8. dissolutionthe obtained residue was dissolved in ethyl acetate
9. additionTo this mixture was added triethylamine (18.1 mL)
10. stirringby stirring at 78° C. overnight
11. temperatureAfter cooling to room temperature
12. concentrationthe reaction mixture was concentrated under reduced pressure
13. customthe obtained residue was purified by silica gel column chromatography (hexane:ethyl acetate=100:0 to 70:30)