4-Nitrobenzoic Acid → Menthol

Participants

Reaction Steps

After L-menthol (300 mg, 1.92 mmol), triphenylphosphine (605 mg, 2.30 mmol), 4-nitrobenzoic acid (387 mg, 2.30 mmol), and THF (12 ml) were added to a 50 ml flask, a 40% azodicarboxylic acid diisopropyl ester-toluene solution (1.21 ml, 2.30 mmol) dissolved in THF (6 ml) was added dropwise thereto at 20° C., and the reaction was allowed to proceed for 15 hours. Water (0.5 mL) was added, and concentration was carried out. Then, water (10 ml) was added to the solution, and extraction was carried out using diethyl ether (10 ml,×2). Then, the organic layer was washed with water (10 ml) and saturated salt water (10 ml), and dehumidified with anhydrous magnesium sulfate. Subsequently, a crude product obtained by concentration was purified by column chromatography (silica gel, 5% ethyl acetate-hexane solution) to give (1S,2S,5R)-1-(4-nitrobenzoyloxy)-2-isopropyl-5-methyl cyclohexanol as a white solid substance (423 mg, yield: 72%/L-menthol).

Provenance & Evidence