Sulfuric Acid → rac-(2R,3S,4R,5S)-3-(3-chloro-2-fluoro-phenyl)-4-(4-chloro-3-fluoro-phenyl)-4-cyano-5-(2,2-dimethyl-propyl)-pyrrolidine-2-carboxylic acid

Participants

Reaction Conditions

Reaction Steps

A mixture of rac-(2R,3S,4R,5S)-3-(3-chloro-2-fluoro-phenyl)-4-(4-chloro-3-fluoro-phenyl)-4-cyano-5-(2,2-dimethyl-propyl)-pyrrolidine-2-carboxylic acid tert-butyl ester (0.6 g, 1.15 mmol) was cooled to 0° C., then conc. H2SO4 (2 mL) was added slowly. The reaction was stirred at RT for 2 hours. The mixture was then poured into ice and extracted with EtOAc. The organic phase was separated, dried over Na2SO4, filtered and solvent was removed under reduced pressure to yield a residue that was triturated with ethyl acetate/heptane and the precipitates were collected by filtration and washed with ether to yield the product rac-(2R,3S,4R,5S)-3-(3-chloro-2-fluoro-phenyl)-4-(4-chloro-3-fluoro-phenyl)-4-cyano-5-(2,2-dimethyl-propyl)-pyrrolidine-2-carboxylic acid (0.526 g, 98.1%) as a white solid. HRMS (ES+) m/z Calcd for C23H22Cl2F2N2O2S+H [(M+H)+]: 467.1099. found: 467.1097.

Provenance & Evidence