Hydrochloric Acid → (2S)-N,N-dibenzyl-3-[4-(cyclopropylmethyl)piperazin-1-yl]-2-methoxy-propan-1-amine

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Reaction Steps

Tert-butyl 4-[(2S)-3-(dibenzylamino)-2-methoxy-propyl]piperazine-1-carboxylate 35b (2.10 g, 4.60 mmol) was dissolved in 30 mL of dichloromethane followed by the addition of 20 mL of a 4 M solution of hydrogen chloride in dioxane. The reaction solution was stirred for 0.5 hours. The resulting solution was concentrated under reduced pressure. The residue was added with 40 mL of acetonitrile. In an ice-water bath, the resulting solution was added with triethylamine (2.09 g, 20.70 mmol), stirred for 0.5 hours followed by the addition of bromomethyl-cyclopropane (0.88 g, 6.47 mmol). The reaction solution was stirred for 12 hours. The resulting solution was concentrated under reduced pressure, added with 20 mL of saturated sodium bicarbonate solution and extracted with ethyl acetate (50 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 (2S)—N,N-dibenzyl-3-[4-(cyclopropylmethyl)piperazin-1-yl]-2-methoxy-propan-1-amine 35c (1.52 g, yield: 81.3%) as a brown oil.

Provenance & Evidence