反应详情

Ethyl 4-ethoxybenzoate (45.3 mL, 250 mmole) was added to a suspension of sodium ethoxide (17.0 g, 250 mmole) and acetonitrile (16 mL, 300 mmole) in dry toluene (100 mL) and the mixture was mechanically stirred at 106°-110° for 26 hours. The reaction was then cooled and diluted with water (400 mL). After most of the solid had dissolved, the solution was washed with ethyl ether (2×200 mL) and then acidified with concentrated HCl (approximately 20 mL) to pH of about 5. The copious off-white precipitate was collected by suction filtration and air dried. Crystallization from 95% ethanol (350 mL) provided 21.3 g. of the subtitled compound as white needles, sufficiently pure for further transformation (yield: 45%). 1H NMR (CDCl3, δ) 7.85 (d, 2H, J=8 Hz, o-phenyl), 6.95 (d, 2H, J=8 Hz, m-phenyl), 4.1 (q, 2H, J= 7 Hz, OCH2), 4.0 (s, 2H, CH2CN), 1.45 (t, 3H, CH3).

1. temperatureThe reaction was then cooled
2. dissolutionAfter most of the solid had dissolved
3. washthe solution was washed with ethyl ether (2×200 mL)
4. filtrationThe copious off-white precipitate was collected by suction filtration and air
5. customdried
6. customCrystallization from 95% ethanol (350 mL)
7. customprovided 21.3 g