反应详情

To a cold (0° C.) solution of 2-amino-4-(4-bromophenyl)-thiophene-3-carboxylic acid ethyl ester (1.0 g, 3.1 mmol) and triethylamine (0.64 mL, 4.60 mmol) in methylene chloride (6 mL) was added cyanoacetic acid chloride (6.82 mL, 3.41 mmol, 0.5 M in methylene chloride). The cold bath was removed, and the reaction was stirred for 2 h. Saturated aqueous sodium bicarbonate solution (5 mL) was added to the reaction at room temperature. The layers were separated, and the aqueous was extracted with additional methylene chloride (3×5 mL). The combined organic layers were dried with anhydrous sodium sulfate, filtered, and concentrated under reduced pressure to provide the titled compound as a yellow solid. MS (ESI) m/e 393 (M−H)−, NMR (300 MHz, CDCl3): δ ppm 12.0 (br s, 1H), 7.47 d, 2H), 7.16 (d, 2H), 6.68 (s, 1H), 4.16 (q, 2H), 3.69 (s, 2H), and 100 (t, 3H).

1. customThe cold bath was removed
2. additionSaturated aqueous sodium bicarbonate solution (5 mL) was added to the reaction at room temperature
3. customThe layers were separated
4. extractionthe aqueous was extracted with additional methylene chloride (3×5 mL)
5. dry with materialThe combined organic layers were dried with anhydrous sodium sulfate
6. filtrationfiltered
7. concentrationconcentrated under reduced pressure