Methanesulfonyl chloride → (S)-4-(tert-butoxycarbonyl)-1-(3-chlorophenyl)-5-[2-(methanesulfonyloxy)ethyl]piperazin-2-one

Participants

Reaction Steps

To a solution of the alcohol from Step E (3.58 g, 10.1 mmol) in 50 mL of dichloromethane at 0° C. was added diisopropylethylamine (3.5 mL, 20.2 mmol), followed by methanesulfonyl chloride (0.936 mL, 12.1 mmol). The solution was stirred for 45 minutes, then quenched with 10% citlic acid. The solution was washed with brine, dried (Na2SO4), filtered, and concentrated in vacuo to provide the crude product which was used in the next step without further purification.

Provenance & Evidence