Isopropylamine → 1,1-dimethylethyl 4-[4-bromo-1-(phenylsulfonyl)-1H-pyrrolo[2,3-b]pyridin-2-yl]-4-hydroxy-1-piperidinecarboxylate

Participants

Reaction Conditions

Reaction Steps

To a solution of isopropylamine (5.5 mmol) in THF (15 mL) cooled to −78° C. was added n-BuLi (2.5 M in hexanes, 5.5 mmol) dropwise. After stirring at −78° C. for 20 min a solution of 4-bromo-1-(phenylsulfonyl)-1H-pyrrolo[2,3-b]pyridine (5.0 mmol) in THF (5.0 mL) was added dropwise. The resulting orange solution was stirred at −78° C. for 2 h, followed by dropwise addition of a solution of 1,1-dimethylethyl-4-oxo-1-piperidinecarboxylate (6.1 mmol) in THF (5.0 mL). After an additional 1.5 h at −78° C., the reaction mixture was warmed to room temperature and quenched with saturated NH4Cl(aq). Extraction with EtOAc (3□), washing with brine, drying (Na2SO4), filtration and concentrated in vacuo provided crude material which was purified by flash chromatography (120 g SiO2, 0-5% EtOAc in CHCl3) to give the title compound as a white solid (85%). ESMS [M+H]+: 536.0.

Provenance & Evidence