反应详情

温度

0 °C

In a flame dried round-bottomed flask equipped with a magnetic stir bar and under inert atmosphere (N2), a solution of 1-(4-hydroxymethyl-pyridin-2-yl)-ethanone (165 mg, 1.09 mmol) in dry CH2Cl2 (5 mL) was treated at 0° C. with Et3N (0.20 mL, 1.43 mmol) followed by DMAP (13 mg, 0.10 mmol) and Ms-Cl (0.11 mL, 1.39 mmol). After stirring at 0° C. for 1 h30, the reaction was quenched with water (5 mL). The org. layer was dried over MgSO4, filtered, and the solvent was removed under reduced pressure to give crude methanesulfonic acid 2-acetyl-pyridin-4-ylmethyl ester as a brown oil. The crude material (250 mg) was dissolved in acetone (8 mL) under inert atmosphere (N2). 4-Nitro-1H-pyrazole (139 mg, 1.09 mmol) was added followed by K2CO3 (761 mg, 5.45 mmol) and TBA bromide (70 mg, 0.22 mmol). The reaction mixture was stirred at rt for 2 h and concentrated to dryness. The residue was partitioned between water (5 mL) and EA (10 mL). The layers were separated and the aq. layer extracted with EA (2×10 mL). The combined org. extracts were dried over MgSO4, filtered, and the solvent removed under reduced pressure. Purification of the residue by FC (10:1 to 2:1 hept-EA) gave the title compound as a yellow oil. TLC: rf (1:2 hept-EA)=0.41. LC-MS-conditions 02: tR=0.84 min, [M+H]+=247.33.

1. customthe reaction was quenched with water (5 mL)
2. dry with materiallayer was dried over MgSO4
3. filtrationfiltered
4. customthe solvent was removed under reduced pressure