Methyl acetoacetate → 1-tert-Butyl-3-cyclobutyl-4-methyl-1,7-dihydro-pyrazolo[3,4-b]pyridin-6-one
反応式
[C:1]([N:5]1[C:9]([NH2:10])=[CH:8][C:7]([CH:11]2[CH2:14][CH2:13][CH2:12]2)=[N:6]1)([CH3:4])([CH3:3])[CH3:2].[C:15](OC)(=[O:20])[CH2:16][C:17]([CH3:19])=O>C(O)(=O)C>[C:1]([N:5]1[C:9]2[NH:10][C:15](=[O:20])[CH:16]=[C:17]([CH3:19])[C:8]=2[C:7]([CH:11]2[CH2:14][CH2:13][CH2:12]2)=[N:6]1)([CH3:4])([CH3:2])[CH3:3]参加物
4
反応条件
- 温度
- 105 °C
実験手順
To 2-tert-butyl-5-cyclobutyl-2H-pyrazol-3-ylamine (5.0 g, 25.9 mmol) in acetic acid (25 mL) was added methyl acetoacetate (5.5 mL, 51.8 mmol), and the reaction was heated to 105° C. After 19 hr, the reaction mixture was cooled to room temperature, concentrated to a viscous oil, and then taken up in EtOAc. The reaction mixture was quenched by the slow addition of an aqueous solution of NaHCO3. The layers were separated and the organic layer was dried over MgSO4, filtered, and concentrated under reduced pressure. Purification of this material was accomplished by trituration with hexanes to give, after two crops, the title compound (0.7 g, 52% yield) as a colorless solid. 400 MHz 1H NMR (CD3OD) d 6.09 (s, 1H), 3.83 (dddd, J=8.3, 8.3, 8.3, 8.3 Hz, 1H), 2.50-2.27 (m, 7H), 2.08-2.01 (m, 1H), 1.99-1.85 (m, 1H), 1.71 (s, 9H). LRMS m/z (APCI+) 260 (M+1).