Dichloromethane → rac-(2R,3S,4R,5S)-3-(3-chloro-2-fluoro-phenyl)-4-(4-chloro-3-methyl-phenyl)-4-cyano-5-(2,2-dimethyl-propyl)-pyrrolidine-2-carboxylic acid tert-butyl ester

Participants

Reaction Steps

To a solution of [3-cyclopropyl-3-methyl-but-(E)-ylideneamino]-acetic acid tert-butyl ester prepared in Example 1a (0.93 g, 7.3 mmol) and To a solution of [3-cyclopropyl-3-methyl-but-(E)-ylideneamino]-acetic acid tert-butyl ester prepared in Example 99a (1.6 g, 7.3 mmol) and (Z)-3-(3-chloro-2-fluoro-phenyl)-2-(4-chloro-2-fluoro-phenyl)-acrylonitrile (1.5 g, 4.9 mmol) prepared in Example 100a in dichloromethane (100 mL) were added triethylamine (1.7 g, 12 mmol) and AgF (0.9 g, 7.3 mmol), in one portion. The mixture was stirred at room temperature for 18 h. The mixture was then quenched with sat. NH4Cl and extracted with CH2Cl2. The organic phase was separated, filtered through celite and dried over Na2SO4, and concentrated. The residue was dissolved into tert-butanol (30 mL), and DBU (5 mL) was added. The mixture was heated at 100° C. for 18 h, then cooled to room temperature, and concentrated. The residue was partitioned between ethyl acetate and water. The organic layer were separated, dried over MgSO4, and concentrated. The residue was purified by chromatography (EtOAc:hexanes=1:10, 1:5) to give rac-(2R,3S,4R,5S)-3-(3-chloro-2-fluoro-phenyl)-4-(4-chloro-3-methyl-phenyl)-4-cyano-5-(2,2-dimethyl-propyl)-pyrrolidine-2-carboxylic acid tert-butyl ester as a white foam (2 g, 80%).

Provenance & Evidence