1-(4-methoxybenzyl)-4-(2-fluoro-4-nitrophenoxy)-3-iodo-1H-pyrazolo[3,4-b]pyridine → 3-Fluoro-4-((3-iodo-1-(4-methoxybenzyl)-1H-pyrazolo[3,4-b]pyridin-4-yl)oxy)aniline

Participants

Reaction Conditions

Reaction Steps

A stirred mixture of 1-(4-methoxybenzyl)-4-(2-fluoro-4-nitrophenoxy)-3-iodo-1H-pyrazolo[3,4-b]pyridine (10.4 g, 20.0 mmol), stannous chloride-dihydrate (22.6 g, 100.0 mmol), and absolute EtOH (200 mL) was heated to 65° C. for 1.5 hours under N2. After cooling to room temperature, the reaction was concentrated in vacuo, and then diluted with DCM (100 mL) and water (100 mL). Aqueous 2N NaOH was added until the pH of the aqueous phase was in the 11-12 range. The biphasic suspension was filtered through a pad of celite, rinsing with DCM (3×100 mL). The filtered biphase was separated, and the aqueous phase was re-extracted with DCM (3×75 mL). The combined organic phases were dried (Na2SO4), filtered, and concentrated. Yield: 7.90 g, 78%. The product was used in the next step without purification. 1H NMR (400 MHz, CDCl3) δ 8.30 (d, J=6 Hz, 1H), 7.35 (d, J=9 Hz, 2H), 7.03 (t, J=9 Hz, 1H), 6.83 (d, J=9 Hz, 2H), 6.53 (m, 2H), 6.24 (m, 1H), 5.61 (s, 2H), 3.81 (s, 2H), 3.76 (s, 3H).

Provenance & Evidence