Benzyl Bromide → tert-butyl 4-[(2S)-3-(dibenzylamino)-2-hydroxy-propyl]piperazine-1-carboxylate

Participants

Reaction Conditions

Reaction Steps

Tert-butyl 4-[(2S)-3-amino-2-hydroxy-propyl]piperazine-1-carboxylate 7c (5 g, 19.30 mmol), potassium carbonate (10.70 g, 77.20 mmol) and benzyl bromide (7.90 g, 46.30 mmol) were dissolved in 120 mL of the mixture solvent of ethanol and water (V/V=5:1). The reaction solution was heated to 60° C. and stirred for 2 hours. The reaction solution was concentrated under reduced pressure, added with 100 mL of water and extracted with ethyl acetate (100 mL×3). The combined organic phase was washed with saturated sodium chloride solution (50 mL), then dried over anhydrous magnesium sulfate, filtered and the filtrate was concentrated under reduced pressure. The resulting residue was purified by silica gel column chromatography to obtain the title compound tert-butyl 4-[(2S)-3-(dibenzylamino)-2-hydroxy-propyl]piperazine-1-carboxylate 35a (3.65 g, yield: 43.0%) as a light yellow oil.

Provenance & Evidence