Trifluoroacetic acid → 2(R)-[(3,4-methylendioxybenzyl)-(2,6-dimethyl-4-methoxybenzenesulfonyl)amino]-3-methanesulfonylamino-propionic acid

Participants

Reaction Steps

A solution of tert-butyl 2(R)-[(3,4-methylendioxybenzyl)-(2,6-dimethyl-4-methoxybenzenesulfonyl)amino]-3-methanesulfonylamino-propionate (1.37 g, 2 mmol) in 20% trifluoracetic acid-methylene chloride (15 ml) was stirred for 1 hour. Extra trifluoroacetic acid (0.5 ml) was added and stirring continued for two hours. The material was then condensed on the rotary evaporator and the residue was taken up in toluene (40 ml) and again condensed. This procedure was repeated twice (2×40 ml toluene, to remove traces of trifluoracetic acid) to provide 2(R)-[(3,4-methylendioxybenzyl)-(2,6-dimethyl-4-methoxybenzenesulfonyl)amino]-3-methanesulfonylamino-propionic acid as a tan green foamy solid (1.02 g).

Provenance & Evidence