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

Participants

Reaction Conditions

Reaction Steps

To a solution of trans-N-Boc-4-hydroxy proline methyl ester (17.6 g) (0.072 mol) and TEA (12.5 mL) (0.09 mol) in 100 mL of DCM at 0° C. was slowly added methanesulfonyl chloride (7 mL) (0.09 mol). The temperature was allowed to warm to 20° C., and the mixture was stirred overnight. Insoluble material was removed by filtration and the organic layer washed with water, dried over MgSO4, and evaporated in vacuo to afford the above-titled compound as an oil which solidified upon standing (24 g). NMR(CDCl3, 200 MHz): 5.22 (1H, m), 4.32-4.5 (1H, m), 3.5-3.9 (5H, m), 3.05 (3H, s), 2.5-2.73 (1H, m), 2.15-2.35 (1H, m), 1.35-1.5 (9H).

Provenance & Evidence