Iodine → 7-Iodo-1-methyl-6-tosyl-1,6-dihydropyrazolo[3,4-d]pyrrolo[2,3-b]pyridine

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Reaction Conditions

Reaction Steps

Diisopropylamine (4.32 mL, 30.6 mmol) in THF (20 mL) was cooled to −74° C. n-BuLi (1.6 M in cyclohexane, 21.04 mL, 33.7 mmol) was added drop-wise over 15 min. After about 20 min, the mixture was added to 1-methyl-6-tosyl-1,6-dihydropyrazolo[3,4-d]pyrrolo[2,3-b]pyridine (5.0 g, 15 mmol) in THF (100 mL) at about −74° C. over about 10 min. After about 1 h, a solution of iodine (4.51 g, 17.7 mmol) in THF (30 mL) was added over about 20 min. The mixture was stirred at about −74° C. for about 3 h and then allowed to warm to rt and stirred overnight. To the mixture was added water (80 mL) and the mixture was extracted with EtOAc (3×100 mL). The organic layers were combined, dried over anhydrous MgSO4 and concentrated under reduced pressure. The residue was purified by flash chromatography with a gradient of 0 to 80% EtOAc/heptane to give 7-iodo-1-methyl-6-tosyl-1,6-dihydropyrazolo[3,4-d]pyrrolo[2,3-b]pyridine (2.08 g, 30%): LC/MS (Table 2, Method a) Rt=2.44 min; MS m/z 453 (M+H)+.

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