Hydrochloric Acid → 2-tert-Butoxycarbonylamino-3-methylsulfonylpropanoic acid methyl ester

Participants

Reaction Steps

A solution of N-tert-butoxycarbonylserine (1.1 g, 5.0 mmol) and triethylamine (0.84 mL, 6.0 mmol) in dichloromethane (50 mL) was cooled to 0° C. and treated with methylsulfonyl chloride (0.44 mL, 5.8 mmol)). After stirring an additional 2 h, the reaction mixture was acidified with 2% HCl (20 mL) and extracted with dichloromethane (3×20 mL). The combined organic layers were washed successively with sat. aq NaHCO3, and sat. aq NaCl, dried over MgSO4 and concentrated. Purification by flash column chromatography (5% ethyl acetate in heptane) gave the desired product (1.25 g, 84%) as an oil. 1H NMR (CDCl3), 5.71 (d, J=7 Hz, 1 H), 4.56 (m, 3 H), 3.82 (s, 3 H), 3.02 (s, 3 H), 1.44 (s, 9 H).

Provenance & Evidence