Diisopropylethylamine → HCID 68618257, compound

Participants

Reaction Steps

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 (200 mg, 0.43 mmol), azetidine-3-carboxylate methyl ester hydrochloride (200 mg, 1.32 mmol), 2-(7-azabenzotriazol-1-yl)-n,n,n′,n′-tetramethyluronium hexafluorophosphate (HATU, 243.3 mg, 0.64 mmol) and iPr2NEt (0.22 mL, 1.2 mmol) in CH2Cl2 (10 mL) was stirred at rt overnight. The mixture was then diluted with CH2Cl2 and washed with water, brine. The organic phase was separated, dried over Na2SO4 and filtered. The mixture was then concentrated and purified by reverse phase chromatography (20-95% of ACN/water) to yield 1-[(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-carbonyl]-azetidine-3-carboxylic acid methyl ester (26 mg, 10.7%). The ester was taken directly to the hydrolysis step by dissolved in THF (0.6 mL) and methanol (0.2 mL), then 2N LiOH (0.2 mL) was added and stirred at room temperature for 3 hours. The mixture was concentrated and diluted with water and ethyl acetate. The organic phase was separated then concentrated to rac-1-[(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-carbonyl]-azetidine-3-carboxylic acid (11.8 mg, 46.6%) as an off-white powder. HRMS (ES+) m/z Calcd for C27H27Cl2F2N3O3+H [(M+H)+]: 550.1471. found: 550.1471.

Provenance & Evidence