Triethylamine → 1-tert-Butyl 2-methyl (2S,4R)-4-((methanesulfonyl)oxy)pyrrolidine-1,2-dicarboxylate

Participants

Reaction Steps

To a solution of (2S,4R)-1-t-butoxycarbonyl-4-hydroxy-2-methoxycarbonylpyrrolidine (53.4 g) in dichloromethane (500 ml) were added triethylamine (36 ml) and methanesulfonyl chloride (19.8 ml) under ice bath cooling and the mixture was stirred at the same temperature for 3 hours. The solution was washed successively with diluted hydrochloric acid, saturated aqueous sodium bicarbonate and brine and dried over magnesium sulfate. The solvent was evaporated in vacuo and the residue was crystallized from n-hexane to give (2S,4R)-1-t-butoxycarbonyl-4-methylsulfonyloxy-2-methoxycarbonylpyrrolidine (56.2 g) as colorless crystal.

Provenance & Evidence