反应详情

温度

70 °C

A mixture of 5-iodosalicylaldehyde (16.2 g, 65.3 mmol), ethyl 4,4,4-trifluorocrotonate (22.4 g, 133 mmol) and triethylamine (50 ml, 395 mmol)were combined, stirred at 70° C. for 8 h and then heated at reflux for 48 h. The solution was poured into ethyl acetate (300 mL) and washed with 1N hydrochloric acid (3×200 mL). The aqueous layers were combined and extracted with ethyl acetate (1×100 mL). The combined ethyl acetate extracts were washed with saturated ammonium chloride (2×200 mL), dried over magnesium sulfate and concentrated in vacuo yielding a dark red oil. This oil was purified by flash chromatography using ethyl acetate-hexanes (3:7) yielding a red oil. Crystallization of this oil from hexanes yielded the title compound as light red crystals (8.3 g, 31%): mp 105-106° C. 1H NMR (CDCl3/300 MHz) 7.63 (s, 1H), 7.58 (dd, 2H, J=8.6, J=2.1 Hz, 7.54 (d, 1H, J=2.1 Hz), 6.77 (d, 1H, J=8.6 Hz), 5.70 (q, 1H, J=6.7 Hz), 4.20-4.38 (m 2H), 1.35 (t, 3H, J=7.2 Hz). ESHRMS 415.9926 (M+NH4+ Calc'd 396.9746).

1. temperatureheated
2. temperatureat reflux for 48 h
3. washwashed with 1N hydrochloric acid (3×200 mL)
4. extractionextracted with ethyl acetate (1×100 mL)
5. washThe combined ethyl acetate extracts were washed with saturated ammonium chloride (2×200 mL)
6. dry with materialdried over magnesium sulfate
7. concentrationconcentrated in vacuo
8. customyielding a dark red oil
9. customThis oil was purified by flash chromatography
10. customyielding a red oil
11. customCrystallization of this oil from hexanes