反応 #10774

反応方程式

hydrochloric acid

2-Hydroxy-4-methoxy-5-thiophen-2-yl-benzaldehyde

4-acetylbenzoic acid

lithium methoxide

→

title compound

収率 15.3%

4-[3E-(2-Hydroxy-4-methoxy-5-thiophen-2-yl-phenyl)-acryloyl]-benzoic acid

収率 15.3%

溶媒

dimethylformamide methanol

water

反応条件

後処理

1. 1
   workup.ADDITIONwas added
2. 2
   抽出extracted with ethyl acetate (3×20 mL)
3. 3
   乾燥The combined organic extracts were dried over sodium sulfate
4. 4
   その他evaporated to dryness
5. 5
   温度warmed to 60° C.
6. 6
   その他to obtain complete
7. 7
   workup.DISSOLUTIONdissolution
8. 8
   温度to cool to room temperature
9. 9
   温度with heating
10. 10
    その他The resulting precipitate was collected
11. 11
    ろ過on filter paper
12. 12
    その他dried in vacuo

実験手順

2-Hydroxy-4-methoxy-5-thiophen-2-yl-benzaldehyde (Ex-29B, 0.10 g, 0.43 mmol) and 4-acetylbenzoic acid (0.070 g, 0.43 mmol) were dissolved in a dimethylformamide-methanol solution (2.8 mL, 7:3). After complete dissolution, lithium methoxide (0.065 g, 1.7 mmol) was added and the resulting red slurry was stirred in the dark at room temperature for 18 h. The mixture was diluted with water (10 mL), acidified with a 1 N hydrochloric acid solution, and extracted with ethyl acetate (3×20 mL). The combined organic extracts were dried over sodium sulfate and evaporated to dryness. The crude oil was taken up in ethyl alcohol (5 mL) and warmed to 60° C. to obtain complete dissolution and allowed to cool to room temperature. Note: the compound appears to decompose with heating. The resulting precipitate was collected on filter paper and dried in vacuo to yield 0.025 g (15%) of the title compound as a dark yellow solid, mp 125° C. (dec). 1H-NMR (300 MHz, DMSO-d6) δ 10.73 (s, 1H), 8.18–8.22 (m, 3H), 8.09 (d, 2H, J=8.1 Hz), 8.05 (s, 1H), 7.87 (d, 1H, J=14.7 Hz), 7.60 (d, 1H, J=3.0 Hz), 7.49 (d, 1H, J=4.2 Hz), 7.11 (dd, 1H, J=4.2, 3.0 Hz), 6.67 (s, 1H), 3.90 (s, 3H). MS (ESI) m/z=381 ([M+H]+, 100%). Anal. Calcd. for C21H16O5S.EtOH: C, 64.77; H, 5.20; S, 7.52. Found: C, 64.68; H, 5.00; S, 7.77.

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