反应详情

温度

-78 °C

To a solution of 5-bromo-3,3-dimethyl-2,3-dihydro-benzofuran (example 1f) (3.3 g, 14.53 mmol) in tetrahydrofuran (30 mL) was added dropwise, at −78° C., under an atmosphere of argon, a solution of n-butyllithium in hexane (8.8 mL, 22 mmol). The mixture was stirred at −78° C. for 5 minutes, then water was added and the mixture was warmed up to room temperature and stirred for 30 minutes. The layers were separated. The aqueous layer was extracted twice with ethyl acetate and the organic combined extract was washed with water, brine, dried (MgSO4), and filtered. The solvent was evaporated to afford 2.13 g of 3,3-dimethyl-2,3-dihydro-benzofuran. 99% yield. 1H-NMR (300 MHz, CDCl3): 1.35 (s, 6H), 4.23 (s, 2H), 6.79 (d, J=7.6 Hz, 1H), 6.88 (t, J=7.3 Hz, 1H), 7.11 (d, J=7.6 Hz, 2H).

1. temperaturethe mixture was warmed up to room temperature
2. stirringstirred for 30 minutes
3. customThe layers were separated
4. extractionThe aqueous layer was extracted twice with ethyl acetate
5. extractionthe organic combined extract
6. washwas washed with water, brine
7. dry with materialdried (MgSO4)
8. filtrationfiltered
9. customThe solvent was evaporated