反应详情

温度

300 °C

Intermediate 9 (0.200 g, 0.702 mmol) was dissolved in formic acid (1.0 ml) and heated to 300° C. and stirred for 12 h. The reaction mixture was poured into ice water and pH adjusted to 7-8 with sodium bicarbonate solution, extracted with ethyl acetate, washed with brine, dried over sodium sulphate and concentrated to afford the title compound as yellowish brown solid (0.200 g, 97% yield). 1H-NMR (δ ppm, DMSO-d6, 400 MHz): δ8.88 (dd, J=4.0, 1.3 Hz, 1H), 8.70 (s, 1H), 8.33 (d, J=8.2 Hz, 1H), 8.19 (d, J=8.3 Hz, 1H), 8.01 (d, J=8.8 Hz, 1H), 7.81 (s, 1H), 7.73 (dd, J=8.7, 1.7 Hz, 1H), 7.52 (dd, J=8.3, 2.2 Hz, 1H), 7.37 (d, J=8.4 Hz, 1H), 5.69 (s, 2H).

1. extractionextracted with ethyl acetate
2. washwashed with brine
3. dry with materialdried over sodium sulphate
4. concentrationconcentrated