N-Fluorobenzenesulfonimide → 3-chloro-N-[3-fluoro-6-methyl-2-(1H-pyrazol-4-yl)thieno[2,3-b]pyridin-4-yl]benzenesulfonamide

Participants

Reaction Conditions

Reaction Steps

A stirred solution of N-[3-bromo-6-methyl-2-(1H-pyrazol-4-yl)thieno[2,3-b]pyridin-4-yl]-3-chlorobenzenesulfonamide (Example 100) (120 mg, 0.248 mmol) in THF (1.5 mL) was cooled to −78° C. using a dry ice/acetone bath. n-BuLi (2.5M in Hexane) (0.109 mL, 0.273 mmol) was added dropwise and the mixture stirred at −78° C. for ca. 1.5 h. Then, N-fluorobenzenesulfonimide (82 mg, 0.260 mmol), pre-dissolved in THF (0.5 mL), was added dropwise and the mixture stirred at −78° C. for ca. 1 h and then left to stir at RT for 3 days (ca. 89 h). The reaction mixture was then quenched with saturated NH4Cl solution (ca. 20 mL), extracted with ethyl acetate (20 mL×3) and the combined organics dried and concentrated. The residue was purified by normal phase chromatography, eluting with a gradient of 0-100% ethyl acetate in DCM and further purified by MDAP (acidic conditions), to give the title compound (5 mg). LCMS (A) m/z: 423 [M+1]+, Rt 1.20 min (acidic).

Provenance & Evidence