反应详情

A solution of 4-benzyloxy-3-chloro-5-methoxy-benzoic acid benzyl ester (CAB02162, 3.83 g, 10.0, mmol) in THF (20 mL) was added dropwise with a syringe to a suspension of lithium aluminium hydride (500 mg, 13.15 mmol) in THF (30 mL). The mixture was stirred at room temperature for 30 minutes and 2N NaOH (5 mL) was added. The mixture was stirred for another hour, the aluminium salts were filtered off, the filtrate was dried over sodium sulphate and concentrated under reduced pressure. The resulting oil was heated to 120° C. under high vacuum in a kugelrohr-destillation-apparatus to remove benzyl alcohol for 10 h. The product was obtained as a light yellow oil and was used without any further purification. Yield: 2.70 g (97%). 1H-NMR (400 MHz, CDCl3) δ=2.09 (2, 1H, —OH), 3.86 (s, 3H, —OCH3), 4.56 (s, 2H), 5.02 (s, 2H), 6.83 (d, J=2.0 Hz, 1H), 6.95 (d, J=2.0 Hz, 1H), 7.31-7.41 (m, 3H), 7.52-7.55 (m, 2H).

1. stirringThe mixture was stirred for another hour
2. filtrationthe aluminium salts were filtered off
3. dry with materialthe filtrate was dried over sodium sulphate
4. concentrationconcentrated under reduced pressure
5. temperatureThe resulting oil was heated to 120° C. under high vacuum in a kugelrohr-destillation-apparatus
6. customto remove benzyl alcohol for 10 h
7. customThe product was obtained as a light yellow oil
8. customwas used without any further purification