Trifluoroacetic acid → rac-(2R,3S,4R,5S)-3-(3-chloro-2-fluoro-phenyl)-4-(4-chloro-2-fluoro-phenyl)-4-cyano-5-{2,2-dimethyl-4-[2-(2,2,2-trifluoro-acetoxy)-ethoxy]-butyl}-pyrrolidine-2-carboxylic acid trifluoroacetic acid

Participants

Reaction Steps

To a solution of rac-(2R,3S,4R,5S)-5-{4-[2-(tert-butyl-dimethyl-silanyloxy)-ethoxy]-2,2-dimethyl-butyl}-3-(3-chloro-2-fluoro-phenyl)-4-(4-chloro-2-fluoro-phenyl)-4-cyano-pyrrolidine-2-carboxylic acid tert-butyl ester prepared in Example 119b (0.49 g, 0.55 mmol) in dichloromethane (3 mL) at room temperature was added trifluoroacetic acid (3 mL). The reaction mixture was stirred at room temperature for 18 h. The mixture was concentrated under reduced pressure to give rac-(2R,3S,4R,5S)-3-(3-chloro-2-fluoro-phenyl)-4-(4-chloro-2-fluoro-phenyl)-4-cyano-5-{2,2-dimethyl-4-[2-(2,2,2-trifluoro-acetoxy)-ethoxy]-butyl}-pyrrolidine-2-carboxylic acid trifluoroacetic acid as a yellow oil (0.37 g, 97%).

Provenance & Evidence