Triethylamine → (S)-2-((tert-Butoxycarbonyl)amino)-3-phenylpropyl methanesulfonate

Participants

Reaction Conditions

Reaction Steps

A solution of (2S)-2-(tert-butoxycarbonylamino)-3-phenyl-1-propanol (3.0 g, 11.9 mmol) in anhydrous CH2Cl2 (120 mL) at 0° C. under a dry N2 atmosphere was treated with triethylamine (3.5 mL, 25.1 mmol) followed by dropwise addition of methanesulfonyl chloride (1.0 mL, 13.1 mmol). After stirring for 2 hours at 0° C., the solution was washed with brine (100 mL), dried over Na2SO4, filtered and concentrated to a reduced volume (20 mL). The mixture was diluted with hexanes (100 mL) and allowed to stand at ambient temperature overnight. Colorless crystals were collected by filtration and dried under reduced pressure to provide the title compound (3.60 g, 92%). Rf=0.26 (hexanes:ethyl acetate, 2:1); 1H NMR (CDCl3) δ 7.36-7.18 (m, 5H), 4.71 (br s, 1H), 4.28-4.05 (m, 3H), 2.99-2.81 (m, 2H), 1.40 (s, 9H); MS (APCl+) m/z 254 (M+H)+.

Provenance & Evidence