2-Fluoro-4-iodopyridine-3-carbaldehyde → 3-(4-iodo-1H-pyrazolo[3,4-b]pyridin-1-yl)benzenesulfonamide

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Reaction Conditions

Reaction Steps

To a 45 mL pressure bottle was added 2-fluoro-4-iodonicotinaldehyde (1.05 g, 4.18 mmol), 3-hydrazinylbenzenesulfonamide (800 mg, 4.27 mmol), and anhydrous NMP (15 mL). The reaction mixture was flushed with argon, securely capped, and heated at 185° C. for 6.5 h. The reaction mixture was cooled to room temperature and slowly added to a rapidly stirred solution of diethyl ether (430 mL). The resulting solid material was filtered and the pale yellow Et2O filtrate was allowed to stand for 18 h at room temperature. The yellow crystals precipitated out and were collected by vacuum filtration to give 425 mg (16.42%) of the title compound as a yellow solid as a “dot” 2 NMP complex by proton NMR. LC/MS (Condition B): ret. T=3.2 min, (M+H)+ 400.83. 1H NMR (500 MHz, DMSO-d6) δ ppm 7.56 (s, 2 H) 7.78-7.84 (m, 2 H) 7.89-7.92 (m, 1 H) 8.37-8.42 (m, 2 H) 8.57 (dt, J=4.81, 2.33 Hz, 1 H) 8.75 (s, 1 H). Second and third crops of yellow solid (300 mg, 11.7%; 246 mg, 9.4%) were identical to the first crop of material.

Provenance & Evidence