Hydrochloric Acid → (2S,trans)-4-Nitrobenzyl 2-(hydroxymethyl)-4-((methylsulfonyl)oxy)pyrrolidine-1-carboxylate

Participants

Reaction Conditions

Reaction Steps

To a solution of (2S,4R)-1-p-nitrobenzyloxycarbonyl-4-methanesulfonyloxypyrrolidine-2-carboxylic acid methyl ester (79.4 g: 0.197 mmole) in a mixture of ethanol (300 ml) and tetrahydrofuran (150 ml), sodium borohydride (10.44 g: 1.4 eq.) is added in small portions with stirring at 0° C. The mixture is stirred at 0° C. for 1.5 hours and at room temperature for 5 hours. To the reaction mixture under ice cooling, 5N-hydrochloric acid (100 ml) is added. The mixture is diluted with water, and extracted with ethyl acetate. The extract is washed with brine, dried over sodium sulfate, and concentrated in vacuo. The residue is recrystallized from a mixture of dichloromethane and ether to give (2S,4R)-1-p-nitrobenzyloxycarbonyl-4-methanesulfonyloxypyrrolidine-2-methanol (51.9 g). Yield: 70%.

Provenance & Evidence