反应详情

A 500 mL 3-neck round bottom flask equipped with a magnetic stirrer, condenser, thermometer and nitrogen bubbler was charged with 19.1 g (82 mmol) of 2-(2-cyanophenyl)-5-methylbenzofuran, 200 mL of toluene and 25.6 g (124 mmol) of trimethyltin azide. The suspension was heated at reflux for 20 hours, then an additional 10.0 g (48 mmol) of trimethyltin azide was added and heating at reflux was continued for another 24 hours. Additional trimethyltin azide (5.8 g, 27 mmol) was added and refluxing continued for 5 hours. The reaction mixture was cooled to room temperature and solids were removed by filtration and washed with hexane and air dried. The solids were partitioned between 400 mL of 2N aqueous sodium hydroxide and 400 mL of ethyl acetate. The layers were separated and the aqueous layer was acidified by the addition of 2N hydrochloric acid, then extracted with 100 mL of ethyl acetate. The combined extracts were washed with saturated aqueous sodium chloride, dried over magnesium sulfate, filtered and refrigerated for 48 hours. The crystals that formed were removed by filtration, washed with hexane and air dried to give 12.97 g (47 mmol, 57%) of the product as fluffy, white crystals. 1H NMR (200 MHz,CDCl3): 2.38 (s,3H), 6.27 (s,1H), 7.05 (d,8 Hz,1H), 7.25 (m,2H), 7.4-7.7 (m,3H), 7.90 (d,8 Hz,1H).

1. customA 500 mL 3-neck round bottom flask equipped with a magnetic stirrer, condenser
2. temperatureThe suspension was heated
3. temperatureat reflux for 20 hours
4. temperatureheating
5. temperatureat reflux
6. temperaturerefluxing
7. waitcontinued for 5 hours
8. customsolids were removed by filtration
9. washwashed with hexane and air
10. customdried
11. customThe solids were partitioned between 400 mL of 2N aqueous sodium hydroxide and 400 mL of ethyl acetate
12. customThe layers were separated
13. additionthe aqueous layer was acidified by the addition of 2N hydrochloric acid
14. extractionextracted with 100 mL of ethyl acetate
15. washThe combined extracts were washed with saturated aqueous sodium chloride
16. dry with materialdried over magnesium sulfate
17. filtrationfiltered
18. waitrefrigerated for 48 hours
19. customThe crystals that formed
20. customwere removed by filtration
21. washwashed with hexane and air
22. customdried