Diphenylphosphinic chloride → rac-(2R,3S,4R,5S)-3-(3-chloro-2-fluoro-phenyl)-4-(4-chloro-2-fluoro-phenyl)-4-cyano-5-(2,2-dimethyl-propyl)-pyrrolidine-2-carboxylic acid {1-[2-(tert-butyl-dimethyl-silanyloxy)-ethyl]-2-oxo-1,2-dihydro-pyridin-4-yl)-amide

Participants

Reaction Steps

To a mixture of rac-(2R,3S,4R,5S)-3-(3-chloro-2-fluoro-phenyl)-4-(4-chloro-2-fluoro-phenyl)-4-cyano-5-(2,2-dimethyl-propyl)-pyrrolidine-2-carboxylic acid (0.2 g, 0.428 mmol) in dichloromethane (20 mL) was added iPr2NEt (138 mg, 1.07 mmol), followed by the addition of diphenylphosphinic chloride (Aldrich) (203 mg, 0.856 mmol). The mixture was stirred at room temperature for 30 min, then 4-amino-1-(2-(tert-butyldimethylsilyloxy)ethyl)pyridin-2(1H)-one (115 mg, 428 μmol) was added. The reaction mixture was stirred at room temperature for 3 h, then concentrated. The residue was purified by flash chromatography (silica gel, 40 g, 5% to 80% EtOAc in hexanes) 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-propyl)-pyrrolidine-2-carboxylic acid {1-[2-(tert-butyl-dimethyl-silanyloxy)-ethyl]-2-oxo-1,2-dihydro-pyridin-4-yl)-amide as a white solid (35 mg, 11%).

Provenance & Evidence