反应详情

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+).

1. extractionthe organic layer was extracted with DCM (2×20 ml)
2. customThe aqueous layers were separated
3. extractionre-extracted with DCM (2×15 ml)
4. dry with materialThe combined organics were dried (MgSO4)
5. concentrationconcentrated in vacuo to a yellow solid which
6. customwas purified by column chromatography