反应详情

A suspension of 1-tritylpyrazolo[5,4-b]pyridine-4-carboxylic acid (3.996 g, 9.856 mmol) in DMF (70.01 mL) was treated sequentially with triethylamine (2.194 g, 3.022 mL, 21.68 mmol), ammonium chloride (2.636 g, 1.723 mL, 49.28 mmol) and TBTU (4.746 g, 14.78 mmol) at RT under nitrogen. The reaction was allowed to stir for 4 hours and then treated with DCM and saturated aqueous NH4Cl. The aqueous was extracted twice with DCM and the organic layer washed with aqueous NH4Cl, followed by 0.5M NaOH, dried (MgSO4), filtered and concentrated. The residue was purified by column chromatography (70:9:1 DCM/MeOH/NH4OH) to give the product as white solid (3.08 g, 77% Yield). 1H NMR (DMSO, 400 MHz) δ 7.18-7.29 (15H, m), 7.44 (1H, m), 7.83 (1H, br s), 8.27 (1H, br s), 8.37 (1H, m), 8.46 (1H, m); MS (ES+) 405.12

1. extractionThe aqueous was extracted twice with DCM
2. washthe organic layer washed with aqueous NH4Cl
3. dry with materialdried (MgSO4)
4. filtrationfiltered
5. concentrationconcentrated
6. customThe residue was purified by column chromatography (70:9:1 DCM/MeOH/NH4OH)