123320-44-5

(3-(Benzyloxy)isoxazol-5-yl)methanol is a key precursor to tetracycline antibiotics.

General procedure for the synthesis of (3-(benzyloxy)isoxazol-5-yl)methanol from methyl 3-(benzyloxy)isoxazole-5-carboxylate: to a solution of methyl 3-(benzyloxy)isoxazole-5-carboxylate (2.33 g, 9.99 mmol, 1.00 eq.) in methanol (50 mL) was added sodium borohydride (756 mg, 19.98 mmol, 2.00 equivalent). The reaction mixture was stirred at 15 °C for 3 hours. The progress of the reaction was monitored by thin layer chromatography (TLC, unfolding agent ratio of petroleum ether:ethyl acetate = 5:1) to confirm the completion of the reaction. The reaction mixture was slowly poured into 0.2 M hydrochloric acid solution (200 mL) and extracted with ethyl acetate (150 mL x 2). The organic phases were combined, washed with saturated saline (200 mL × 2), dried over anhydrous sodium sulfate, filtered and concentrated under reduced pressure to give (3-(benzyloxy)isoxazol-5-yl)methanol (1.85 g, 9.02 mmol, 90% yield) as a colorless oil.LC-MS (ESI) m/z: 206.1 [M+H]+.

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