Hydrochloric Acid → {1-[2-(4'-Chloro-biphenyl-3-ylcarbamoyl)-pyrrolidine-1-carbonyl]-2-methyl-propyl}-carbamic acid methyl ester

Participants

Reaction Conditions

Reaction Steps

2-(4′-Chloro-biphenyl-3-ylcarbamoyl)-pyrrolidine-1-carboxylic acid tert-butyl ester (1.66 g, 4.14 mmol) was dissolved in methanol (20 mL) and concentrated HCl (4 mL) was added. The mixture was stirred at 50° C. for 80 min then cooled and concentrated. The residue was treated with 2-methoxycarbonylamino-3-methyl-butyric acid (870 mg, 4.97 mmol) and HATU (2.05 g, 5.38 mmol) and brought up in DMF (20 mL). The mixture was cooled to 0° C. and DIPEA (3.60 mL, 20.7 mmol). After 100 min, the reaction mixture was diluted with ethyl acetate (250 mL) and washed with water and brine. The organic phase was dried over magnesium sulfate and concentrated. The resulting residue was purified by silica column chromatography (50% to 80% EtOAc/hexanes) to afford {1-[2-(4′-Chloro-biphenyl-3-ylcarbamoyl)-pyrrolidine-1-carbonyl]-2-methyl-propyl}-carbamic acid methyl ester (1.83 g, 96% over 2 steps).

Provenance & Evidence