4-Chlorobenzenesulfonyl chloride → tert-butyl (2R)-2-{[(4-chlorophenyl)sulfonyl]amino}propanoate

Participants

Reaction Steps

To D-alanine tert-butyl ester hydrochloride (1 g) in methylene chloride (35 ml) solution, triethylamine (1.7 ml) and 4-chlorobenzenesulfonyl chloride (1.1 g) were added under ice cooling and the mixture was stirred at room temperature for 2 hours. The methylene chloride was distilled off in vacuo, then the residue was diluted with ethyl acetate. The obtained solution was successively washed with distilled water, saturated potassium hydrogensulfate aqueous solution, and saturated saline, dried over with anhydrous sodium sulfate, then concentrated. The residue was recrystallized from ethyl acetate/hexane to obtain the title compound (1.47 g).

Provenance & Evidence