Hydrochloric Acid → (5R)-4-hydroxy-5-(methylamino)-6-phenylhexyl acetate

Participants

Reaction Conditions

Reaction Steps

((1R)-1-Benzyl-2,5-dihydroxypentyl)methylcarbamic acid tert-butylester (560 mg, 1.52 mmol) was dissolved in ethyl acetate (10 mL). 3M Hydrogen chloride in ethyl acetate (2.0 mL, 6.08 mmol) was added. The solution was stirred at room temp. for 1 h. It was diluted with ethyl acetate (10 mL) and extracted with 1N sodium hydroxide solution (30 mL). The aqueous phase was extracted with ethyl acetate (3×10 mL). The combined organic phases were dried over magnesium sulfate. The solvent was removed in vacuo. The residue was dissolved in dichloromethane (5 mL). The solution was cooled to 0° C. Trifluoroacetic acid (5 mL) was added. The solution was stirred at this temp. for 5 min. The solvents were removed in vacuo. The residue was dissolved in ethyl acetate (10 mL). The solution was extracted with 1N sodium hydroxide solution (10 mL). The aqueous phase was extracted with ethyl acetate (2×5 mL). The combined organic layers were dried over magnesium sulfate. The solvent was removed in vacuo. The crude product was purified by flash chromatography on silica (40 g) with dichloromethane/methanol/25% aqueous ammonia 100:10:1 to give 136 mg of (5R)-4-hydroxy-5-(methylamino)-6-phenylhexyl acetate.

Provenance & Evidence