Diphenylphosphinic chloride → tert-butyl 4-((2R,3S,4R,5S)-3-(3-chloro-2-fluorophenyl)-4-(4-chloro-2-fluorophenyl)-4-cyano-5-neopentylpyrrolidine-2-carboxamido)-2-fluorobenzoate

Participants

Reaction Steps

In a 25 mL round-bottomed flask, (2R,3S,4R,5S)-3-(3-chloro-2-fluorophenyl)-4-(4-chloro-2-fluorophenyl)-4-cyano-5-neopentylpyrrolidine-2-carboxylic acid compound with 2,2,2-trifluoroacetic acid (1:1) (200 mg, 344 μmol, Eq: 1.00), was combined with CH2Cl2 (4.5 ml) to give a yellow solution. DIPEA (178 mg, 1.38 mmol, Eq: 4) and diphenylphosphinic chloride (244 mg, 1.03 mmol, Eq: 3) were added and the reaction was stirred at RT for 20 minutes. Tert-butyl 4-amino-2-fluorobenzoate (72.7 mg, 344 μmol, Eq: 1.00) was added and the reaction mixture was stirred at RT overnight. The crude reaction mixture was concentrated under vacuum. The crude material was purified by flash chromatography (silica gel, 40 g, 10% to 20% EtOAc in hexanes) to give a white solid as the product. 215 mg. MS (ES+) m/z Calcd: [(M+H)+]: 660, fund: 660.

Provenance & Evidence