反应详情

Sodium hydride (60% dispersion in mineral oil, 2.17 g, 54.2 mmol) was added portionwise to a stirred solution of 1-(5-chloro-2-methoxy-phenyl)-ethanone (10.0 g, 54.2 mmol) in THF (100 mL) at 0° C. The mixture was then stirred for 10 minutes before addition of diethyl carbonate (7.68 g, 65.0 mmol) and then for an additional 1 hour. The mixture was warmed to room temperature for 2 hours and then heated to 65° C. for 2 hours. Diethyl ether was added, the organics washed with water and brine, then evaporated to dryness. The resultant residue was purified by flash chromatography on silica gel (50 to 100% dichloromethane in cyclohexane) to yield 3.41 g of ethyl 3-(5-chloro-2-methoxyphenyl)-3-oxopropanoate. LCMS (method 1) [M+H]+=257.2, RT=3.55 min. 1H NMR (400 MHz, CDCl3): δ (ppm) 7.59 (d, 1H), 7.38 (dd, 1H), 6.89 (d, 1H), 4.18 (q, 2H), 3.95 (s, 2H), 3.88 (s, 3H), 1.24 (t, 3H).

1. temperatureheated to 65° C. for 2 hours
2. washthe organics washed with water and brine
3. customevaporated to dryness
4. customThe resultant residue was purified by flash chromatography on silica gel (50 to 100% dichloromethane in cyclohexane)