4-Toluenesulfonyl chloride → (2S,4R)-benzyl 4-(tosyloxy)-2-((tosyloxy)methyl)pyrrolidine-1-carboxylate

Participants

Reaction Steps

To an ice-cold solution of 150 g (596.9 mmol) of (2R,4S)-2-hydroxymethyl-4-hydroxy-N-(carbobenzyloxy)pyrrolidine in 0.5 1 of pyridine was added 250 g (1.32 mol) of 4-toluenesulfonyl chloride in 3 portions to keep the temperature of the reaction below 15° C. for 1 hour and then warmed to room temperature. After 12 hours, an additional 125 g (656 mmol) of p-toluenesulfonyl chloride was added and the mixture was allowed to stir at room temperature for 16 additional hours. The mixture was then cooled with an ice bath and 3 1 of 10% aqueous HC1 solution was carefully added. The mixture was extracted with 2 x 250 ml of methylene chloride and dried over MgSO4. Evaporation of the solvent provided 274 g of the product as an oil (82% yield). NMR(CDC13): 7.70 & 7.40 (m,9H, aromatic), 5.0 (m,3H), 4.43 (dd,1H), 4.12 (m,1H), 4.02 (m,H), 3.70 (m,1H), 3.88 (m,1H), 2.42 (m,6H), 2.15 (m,2H).

Provenance & Evidence