反応 #1462130

反応方程式

hydrogen

4-hydroxychroman

acetic anhydride

→

product

収率 85.4%

Chroman

収率 85.4%

溶媒

acetic acid

反応条件

後処理

1. 1
   温度the mixture was heated
2. 2
   温度at reflux for 3 h
3. 3
   ろ過The reaction mixture was filtered
4. 4
   その他the solvent was removed in vacuo
5. 5
   洗浄The solution was washed with saturated aqueous sodium bicarbonate solution, brine
6. 6
   乾燥dried (magnesium sulfate)
7. 7
   濃縮concentrated in vacuo

実験手順

To a stirred solution of 4-hydroxychroman (10.14 g, 67.5 mmol) in acetic acid (150 mL) under Ar was added acetic anhydride (12.7 mL, 135 mmol) and the mixture was heated at reflux for 3 h, then allowed to cool to ambient temperature. Palladium on carbon (10 wt %; 1.8 g, 2.5 mol %) was added and the mixture was shaken in a Parr hydrogenator under a 42 psi atmosphere of hydrogen overnight. The reaction mixture was filtered, the solvent was removed in vacuo and the residue was taken-up in ethyl acetate. The solution was washed with saturated aqueous sodium bicarbonate solution, brine, dried (magnesium sulfate) and concentrated in vacuo to afford the product (7.73 g, 85%) as a pale yellow liquid: IR νmax (film)/cm−1 2937, 2863, 1737, 1609, 1582, 1490, 1456, 1304, 1267, 1228, 1189, 1116, 1065, 1008 and 754; NMR (400 MHz, CDCl3) δH 2.00 (2H, m), 2.78 (2H, t, J 6.5 Hz), 4.17 (2H, t, J 7 Hz), 6.81 (2H, m) and 7.05 (2H, m).

出典