4-Methoxyphenol → (4S,2R)-4-(4-methoxyphenoxy)pentane-2-ol

After 4-methoxyphenol (300 mg, 2.41 mmol), triphenylphosphine (762 mg, 2.89 mmol), (2R,4R)-2,4-pentanediol (303 mg, 2.89 mmol), and THF (12 ml) were added to a 50 ml flask, a 40% azodicarboxylic acid diisopropyl ester-toluene solution (1.53 mL, 2.89 mmol) dissolved in THF (6 ml) was added dropwise thereto at 20° C., and the reaction was allowed to proceed for 17 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, 30% ethyl acetate-hexane solution) to give (4S,2R)-4-(4-methoxyphenoxy)pentane-2-ol containing 1,2-hydrazinedicarboxylic acid diisopropyl ester as 543 mg of a colorless oily substance. Measurement of 1H-NMR showed that 420 mg of (4S,2R)-4-benzoyloxypentane-2-ol (yield: 83%/4-methoxyphenol), and 123 mg of 1,2-hydrazinedicarboxylic acid diisopropyl ester were contained.

1. additionwas added dropwise
2. customat 20° C.
3. concentrationconcentration
4. additionThen, water (10 ml) was added to the solution, and extraction
5. washThen, the organic layer was washed with water (10 ml) and saturated salt water (10 ml)
6. customSubsequently, a crude product obtained by concentration
7. customwas purified by column chromatography (silica gel, 30% ethyl acetate-hexane solution)

ORD-Eintrag

ord-84175c24cbe64aa1bb7d4a4e84c7e28a

Quelldatensatz

uspto-grants-2011_05

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US07947816B2