1-Methylimidazole → 1,1-dimethylethyl (3R)-3-(cyclopentylmethyl)-4-oxo-4-{5-[(2-pyrimidinylamino)carbonyl]-4,5-dihydro-1H-pyrazol-1-yl}butanoate

Participants

Reaction Conditions

Reaction Steps

1-Methyl-1H-imidazole (0.24 mL, 3.0 mmol) was added into 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 dichloromethane (DCM) (5.0 mL). The resulting solution was cooled to 0° C., and then methanesulfonyl chloride (0.08 mL, 1.05 mmol) was added dropwise at 0° C. To the reaction mixture was then added 2-pyrimidinamine (105 mg, 1.1 mmol), and stirring continued for 30 min at room temperature. After this time, the solvent was removed under reduced pressure to provide a residue which was purified by Combiflash automated silica gel chromatography (80-100% EtOAc in Hex) to afford 1,1-dimethylethyl (3R)-3-(cyclopentylmethyl)-4-oxo-4-{5-[(2-pyrimidinylamino)carbonyl]-4,5-dihydro-1H-pyrazol-1-yl}butanoate (270 mg, 0.63 mmol, 63% yield). MS: 430 ([M+H]+).

Provenance & Evidence