反应详情

To a stirred solution of methyl 5-methyl-2-phenyl-7-p-tolylpyrazolo[1,5-a]pyrimidine-6-carboxylate (800 mg, 2.238 mmol) in CH2Cl2 (50 mL) was added DIBAL-H, 1M in THF (6.72 mL, 6.72 mmol) dropwise. The reaction mixture was stirred at room temperature for 1 h before being quenched with saturated NH4Cl solution. The aqueous layer was extracted with CH2Cl2 and the combined organic layer was dried over anhydrous Na2SO4, filtered and concentrated. The residue was purified by silica gel chromatography to give the title compound (344 mg, 46.7%). 1H-NMR (500 MHz, CDCl3) δ ppm 1.61 (1H, t, J=5.0 Hz), 2.49 (3H, s), 2.78 (3H, s), 4.59 (2H, d, J=5.0 Hz), 6.88 (1H, s), 7.29-7.42 (5H, m), 7.56 (2H, d, J=8.2 Hz), 7.81-7.96 (2H, m).

1. custombefore being quenched with saturated NH4Cl solution
2. extractionThe aqueous layer was extracted with CH2Cl2
3. dry with materialthe combined organic layer was dried over anhydrous Na2SO4
4. filtrationfiltered
5. concentrationconcentrated
6. customThe residue was purified by silica gel chromatography