Trifluoroacetic acid → (2s,4s)-1-p-Nitrobenzyloxycarbonyl-2-sulfamoylaminomethyl-4-tritylthiopyrrolidine

Participants

Reaction Steps

To a solution of (2S,4S)-1-p-nitrobenzyloxycarbonyl-2-t-butoxycarbonylaminosulfonylaminomethyl-4-tritylthiopyrrolidine (1.46 g: 2 mmole) in dichloromethane (5 ml) under ice cooling, anisole (2.4 ml) and trifluoroacetic acid (3.9 ml) are added. The mixture is stirred at room temperature for 2 hours. The reaction mixture is diluted with ethyl acetate and ice water and extracted with ethyl acetate. The extract is successively washed with water and saturated brine, dried over magnesium sulfate, and concentrated in vacuo. The residue is recrystallized from n-hexane to give (2S,4S)-1-p-nitrobenzyloxycarbonyl-2-sulfamoylaminomethyl-4-tritylthiopyrrolidine (1.4 g). Yield: Nearly quantitative. NMR δ(CDCl3) ppm: 1.43 to 1.70(m, 1H), 2.08 to 2.30(m, 1H), 2.65 to 3.50(m, 5H), 3.74 to 4.00(m, 1H), 5.03, 5.13(ABq, J=15 Hz, 2H), 5.73(br s, 1H), 7.00 to 7.60(m, 17H), 8.25(d, J=9 Hz, 2H). IR ν (CHCl3) cm-1 : 3334br, 1688, 1607.

Provenance & Evidence