2-(1-Ethoxycarbonyl-2-vinyl-cyclopropylcarbamoyl)-4-(4-nitro-benzoyloxy)-pyrrolidine-1-carboxylic acid tert-butyl ester → 4-Nitro-benzoic acid 5-(1-ethoxycarbonyl-2-vinyl-cyclopropylcarbamoyl)-pyrrolidin-3-yl ester

Participants

Reaction Steps

Compound 133 (6.2 g, 12 mmol) was dissolved in an ice-cold mixture of trifluoro-methanesulfonic acid 33% in dichloromethane. The ice-bath was then removed and the mixture was left at room temperature for ˜1.5 h. The solvent was evaporated and 0.25 M sodium carbonate added and the mixture was extracted with dichloromethane. Evaporation gave the title compound (4.8 g, 95%) as a yellowish powder.

Provenance & Evidence