反应详情

温度

160 °C

Following a standard procedure (Balasubramanian, T. et al., J. Org. Chem. 2000, 65, 7919-7929), a mixture of 6 (6.81 g, 29.7 mmol) and ethylene glycol (76.0 mL) in a 250-mL Claisen flask was flushed with argon for 10 min, and then powdered NaOH (3.05 g, 76.2 mmol) was added. The flask was placed in an oil bath at 120° C. and the oil bath temperature was raised to 160° C. After 2.5 h, the flask was cooled to room temperature and 10% aqueous NaCl (150 mL) was added. The aqueous layer was extracted with CH2Cl2. The organic layers were collected, washed with 10% aqueous NaCl, dried (Na2SO4), concentrated, and chromatographed (silica, CH2Cl2) to give a light brown solid (3.33 g, 71%): mp 92-93° C.; 1H NMR δ 2.34 (s, 3H), 6.51-6.54 (m, 1H), 6.82-6.84 (m, 1H), 7.05-7.08 (m, 1H), 7.15 (d, J=7.8 Hz, 2H), 7.43 (d, J=7.8 Hz, 2H), 8.15-8.32 (br, 1H); 13C NMR δ 21.3, 106.7, 114.4, 119.0, 125.1, 125.4, 129.5, 133.1, 135.2; FAB-MS obsd 157.0885, calcd 157.0891 (C11H11N).

1. customwas flushed with argon for 10 min
2. customThe flask was placed in an oil bath at 120° C.
3. temperaturethe flask was cooled to room temperature
4. extractionThe aqueous layer was extracted with CH2Cl2
5. customThe organic layers were collected
6. washwashed with 10% aqueous NaCl
7. dry with materialdried (Na2SO4)
8. concentrationconcentrated
9. customchromatographed (silica, CH2Cl2)