反应详情

To a solution of tert-butyl 3-(pyridin-4-yl)-5-((triisopropylsilyl)ethynyl)-1H-indazole-1-carboxylate (3.10 g, 6.5 mmol) in THF (100 ml) was added 1M TBAF in THF (7.2 ml, 7.2 mmol). The reaction was stirred for 3 h at room temperature. Upon completion, the reaction mixture was quenched with the addition of saturated aqueous NH4Cl (50 ml) and extracted with Et2O (3×100 ml). The combined organic extracts were washed with saturated aqueous NaCl (100 ml) and dried with anhydrous Na2SO4. The organic phase was concentrated under reduced pressure and column purified (20-80% EtAOc/Hexane) to give the desired product of tert-butyl 5-ethynyl-3-(pyridin-4-yl)-1H-indazole-1-carboxylate (0.77 g) and the de-Boc product of 5-ethynyl-3-(pyridin-4-yl)-1H-indazole (0.40 g).

1. customUpon completion, the reaction mixture was quenched with the addition of saturated aqueous NH4Cl (50 ml)
2. extractionextracted with Et2O (3×100 ml)
3. washThe combined organic extracts were washed with saturated aqueous NaCl (100 ml)
4. dry with materialdried with anhydrous Na2SO4
5. concentrationThe organic phase was concentrated under reduced pressure and column
6. custompurified (20-80% EtAOc/Hexane)