Triethylamine → methyl 4-[(1S)-1-[[(2R)-3-methyl-2-methylsulfonyloxy-butanoyl]amino]ethyl]benzoate

Participants

Reaction Conditions

Reaction Steps

A mixture of methyl 4-[(1S)-1-[[(2R)-2-hydroxy-3-methyl-butanoyl]amino]ethyl]benzoate (40 g; 143 mmol), and triethylamine (22.0 mL, 157 mmol) in CH2Cl2 (400 mL) is cooled to 0° C. A solution of methanesulfonyl chloride (11.1 mL, 143 mmol) in CH2Cl2 (200 mL) is added dropwise over 45 min, and the mixture is stirred to room temperature for 1 h. The mixture is washed sequentially with 1N HCl (100 mL) and aq. NaHCO3 (200 mL). The organic layer is dried over MgSO4, filtered, and concentrated. The crude material is slurried in methyl t-butyl ether (200 mL) and hexane (600 mL) for 30 min, filtered, and dried under vacuum to provide the title compound as a white solid (50 g, 98%). MS (m/z): 358.2 (M+1).

Provenance & Evidence