Реакция #51207

Уравнение реакции

HCl

2,3-Dihydrobenzo[b]furan-5-carboxaldehyde

acetone

NaOH

→

title product

Выход 84.0%

(3E)-4-(2,3-Dihydro-1-benzofuran-5-yl)-3-buten-2-one

Выход 84.0%

Растворители

Water

water

DCM

Условия реакции

Обработка

1. 1
   Экстракцияthe organic layer was extracted with DCM (2×20 ml)
2. 2
   ДругоеThe aqueous layers were separated
3. 3
   Экстракцияre-extracted with DCM (2×15 ml)
4. 4
   СушкаThe combined organics were dried (MgSO4)
5. 5
   Концентрированиеconcentrated in vacuo to a yellow solid which
6. 6
   Другоеwas purified by column chromatography

Методика

2,3-Dihydrobenzo[b]furan-5-carboxaldehyde (Aldrich Chemicals) (2 g, 13.5 mmol), acetone (2.73 ml, 37.1 mmol), water (1.35 ml) and 10% NaOH (aq.) (0.34 ml) were added together and the whole stirred at room temperature for 16 h. The yellow solid was redissolved in approx. 15 ml DCM and 2N HCl added to achieve a solution of pH2. Water (10 ml) was added and the organic layer was extracted with DCM (2×20 ml). The aqueous layers were separated, and re-extracted with DCM (2×15 ml). The combined organics were dried (MgSO4) and concentrated in vacuo to a yellow solid which was purified by column chromatography using 15-30% EtOAc in pentane as eluant to provide the title product (2.13 g, 84%); 1HNMR (400 MHz, CDCl3) δ: 2.3 (s, 3H), 3.2 (t, 2H), 4.6 (t, 2H), 6.5 (d, 1H), 6.75 (d, 1H), 7.3 (d, 1H), 7.4 (s, 1H), 7.45 (d, 1H); LRMS: M+H, 189. (ES+).

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