反应详情

A solution of 2.5M n-BuLi (13.0 ml, 32.5 mmol) was added to a solution of 1,3-dibromo-2-(2-bromo-ethoxy)-benzene (11.5, 32.0 mmol) in 115 ml of THF and 28 m) of hexane at −78° C. over 30 mins. Tire reaction was continued at −78° C. for 30 minutes, then warned to 0° C., The mixture was poured into water (100 ml) and the aqueous phase was extracted with ether. The combined organic layers were dried over Na2SO4, filtered, and concentrated to give a pale yellow oil. Silica gel chromatography using a gradient of ethyl acetate in hexanes to give 7-bromo-2,3-dihydro-benzofuran as colorless needles (5.00 g, 78%). 1H NMR (500 MHz, DMSO-d6) δ 7.27 (dd, 1 Hz, 8 Hz, 1H), 7.20 (dd, 1 Hz, 7.5 Hz, 1H), 6.75 (t, 7.8 Hz, 1H), 4.59 (t, 9 Hz, 2H), 3.28 (t, 8.8 Hz, 2H).

1. customTire reaction
2. customwarned to 0° C.
3. extractionthe aqueous phase was extracted with ether
4. dry with materialThe combined organic layers were dried over Na2SO4
5. filtrationfiltered
6. concentrationconcentrated
7. customto give a pale yellow oil