反応 #51207

反応方程式

HCl

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

acetone

NaOH

→

title product

収率 84.0%

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

収率 84.0%

溶媒

Water

water

DCM

反応条件

後処理

1. 1
   抽出the organic layer was extracted with DCM (2×20 ml)
2. 2
   その他The aqueous layers were separated
3. 3
   抽出re-extracted with DCM (2×15 ml)
4. 4
   乾燥The combined organics were dried (MgSO4)
5. 5
   濃縮concentrated in vacuo to a yellow solid which
6. 6
   その他was purified by column chromatography

実験手順

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+).

出典