反应详情

温度

0 °C

A solution of 141A (7.42 g, 35:6 mmol) and 4-cyanoaniline (4.21 g, 35.6 mmol) in methanol (120 mL) was stirred at 60° C. for 2 h. The reaction was cooled to 0° C. and p-toluenesulfonylmethyl isocyanide (6.95 g, 35.6 mmol) was added followed by dropwise addition of boron trifluoride etherate (13.5 mL, 107 mmol). After stirring for 30 min at 0° C., the reaction was allowed to warm to rt and stirring was continued for 2 h. Water (4 mL) was added and bright yellow precipitate was observed after stirring for 2 days. The solvent was removed and the residue was redissolved in ethyl acetate. The precipitate was filtered and dried to give 7.89 g of 141B as a white solid. 1H NMR (400 MHz, Methanol-d4) δ ppm 1.18-1.20 (m, 6H) 1.28 (t, J=6.98, 3H) 3.62 (s, 3H) 3.90-3.98 (m, 2H) 4.40-4.50 (m, 1H) 5.06 (s, 1H) 6.59 (d, J=8.90 Hz, 2H) 6.80-7.00 (m, 3H) 7.29 (d, J=8.90 Hz, 2H).

1. temperatureto warm to rt
2. stirringstirring
3. waitwas continued for 2 h
4. stirringafter stirring for 2 days
5. customThe solvent was removed
6. dissolutionthe residue was redissolved in ethyl acetate
7. filtrationThe precipitate was filtered
8. customdried