Aniline → 1,1-dimethylethyl (3R)-3-(cyclopentylmethyl)-4-oxo-4-{5-[(phenylamino)carbonyl]-4,5-dihydro-1H-pyrazol-1-yl}butanoate

Participants

Reaction Conditions

Reaction Steps

To a solution of 1-{(2R)-2-(cyclopentylmethyl)-4-[(1,1-dimethylethyl)oxy]-4-oxobutanoyl}-4,5-dihydro-1H-pyrazole-5-carboxylic acid (352 mg, 1.0 mmol) in acetonitrile (10 mL) at 0° C. was added 4-[4,6-bis(methyloxy)-1,3,5-triazin-2-yl]-4-methylmorpholin-4-ium (656 mg, 2.0 mmol) and N-methylmorpholine (0.29 mL, 2.6 mmol). The reaction was stirred for 2 hours at 0° C. Aniline (93 mg, 1.0 mmol) was added to the reaction, which was allowed to warm to room temperature and stirred for 3 hours. The solvent was then removed under reduced pressure, and water (5 mL) and DCM (15 mL) were added to the residue. The phases were separated. The aqueous phase was extracted twice with DCM (15 mL), and the combined organics were dried over sodium sulfate and concentrated. The resulting residue was purified by Combiflash silica gel chromatography (0-60% EtOAc in hex) to give 1,1-dimethylethyl (3R)-3-(cyclopentylmethyl)-4-oxo-4-{5-[(phenylamino)carbonyl]-4,5-dihydro-1H-pyrazol-1-yl}butanoate (386 mg, 0.90 mmol, 90% yield) as a yellow oil. MS: 428 ([M+H]).

Provenance & Evidence