反应详情

温度

60 °C

A 50 mL round bottom flask was charged with 5-formylsalicylaldehyde (3.21 g, 21.39 mmol), ethyl 4,4,4-trifluorocrotonate (3.50 mL, 3.96 g, 23.53 mmol), dimethylformamide (15 mL) and potassium carbonate (2.95 g, 21.39 mmol) and heated to 60° C. for 12 hours. Additional ethyl 4,4,4-trifluorocrotonate (3.50 mL, 3.96 g, 23.53 mmol) was added and the reaction heated for 16 hours at 75° C. After cooling to room temperature, the reaction was partitioned between H2O and diethyl ether. The organic phase was washed with saturated NaHCO3 solution, KHSO4 solution (0.25 M), brine, treated with decolorizing carbon (warmed gently). The resulting black suspension was dried over MgSO4, vacuum filtered through diatomaceous earth, and concentrated in vacuo yielding an orange crystalline mass. This material was recrystallized from hot hexanes yielding the ester (1.51 g, 24%) as orange crystals: mp 84.3–86.2° C. 1H NMR (acetone-d6/300 MHz) 9.96 (s, 1H), 8.06 (d, 1H, J=2 Hz), 8.02 (s, 1H), 7.99 (dd, 1H, J=8.5, 2.0 Hz), 7.24 (d, 1H, J=8.5 Hz), 5.99 (q, 1H, J=7.1 Hz), 4.43–4.25 (m, 2H), 1.34 (t, 3H, J=7.3 Hz). FABLRMS m/z 301 (M+H). EIHRMS m/z 300.0605 (M+, Calc'd 300.0609). Anal. Calc'd for C14H11F3O4: C, 56.01; H, 3.69. Found: C, 56.11; H, 3.73.

1. temperaturethe reaction heated for 16 hours at 75° C
2. temperatureAfter cooling to room temperature
3. customthe reaction was partitioned between H2O and diethyl ether
4. washThe organic phase was washed with saturated NaHCO3 solution, KHSO4 solution (0.25 M), brine
5. additiontreated with decolorizing carbon (
6. temperaturewarmed gently)
7. dry with materialThe resulting black suspension was dried over MgSO4, vacuum
8. filtrationfiltered through diatomaceous earth
9. concentrationconcentrated in vacuo
10. customyielding an orange crystalline mass
11. customThis material was recrystallized from hot hexanes yielding the ester (1.51 g, 24%) as orange crystals