反应详情

温度

60 °C

Acetic anhydride (2.01 mL, 20.6 mmol) was added to formic acid (0.75 mL, 20.6 mmol) at 0° C. The mixture was heated to 60° C. for 30 minutes. After that 2-(6-amino-2,7-naphthyridin-1-yl)isoindoline-1,3-dione 4-7 (300 mg, 1.03 mmol) dissolved in CH2Cl2 (10 mL) was added at 0° C. The mixture was stirred for 1 h at room temperature. The mixture was concentrated and the residue was triturated with CH2Cl2/hexane (1:1) to give 240 mg (73%) of 4-8 as a pale yellow solid: 1H NMR (300 MHz, CDCl3)1H NMR (rotamer ratio: s-cis/s-trans=4:1) δ 9.46 (0.2H, br d, J=10.3 Hz), 9.01 (0.8H, br s), 8.75 (0.2H, br d, J=10.3 Hz), 8.68 (1H, br d, J=5.4 Hz), 8.60 (1H, br s), 8.56 (1H, br s), 8.48 (0.8H, br s), 8.03 (2H, m), 7.86 (2H, m), 7.77 (0.8H, br d, J=5.4 Hz), 7.67 (0.2H, br d, J=5.4 Hz); ESI-MS m/z 319 [C17H10N4O3+H]+.

1. additionwas added at 0° C
2. concentrationThe mixture was concentrated
3. customthe residue was triturated with CH2Cl2/hexane (1:1)