反应详情

To a solution of 6-(benzyloxy)pyridine-2,3-diamine (19.31 g, 89.71 mmol) in THF (300 mL) was added trimethyl orthoformate 99% (99.16 ml, 897.1 mmol) and TFA (345 μL, 4.49 mmol) at room temperature. After stirring for 24 h the solvent was removed under reduced pressure. The residue was taken up in 2 M HCl and EtOAc. The two layers were separated. The organic layer was washed with 2 M HCl and the combined aqueous layers were then made basic by the careful addition of 2 N NaOH. The precipitate was collected by vacuum filtration to give the title compound as a white solid (16.39 g). LCMS m/z=226.3, [M+H]+; 1H NMR (400 MHz, DMSO-d6) δ ppm 5.40 (s, 2H), 6.91 (d, J=9.1 Hz, 1H), 7.32 (m, 1H), 7.38 (m, 2H), 7.48 (m, 2H), 8.09 (d, J=9.1 Hz, 1H), 8.79 (s, 1H).

1. customwas removed under reduced pressure
2. customThe two layers were separated
3. washThe organic layer was washed with 2 M HCl
4. additionthe combined aqueous layers were then made basic by the careful addition of 2 N NaOH
5. filtrationThe precipitate was collected by vacuum filtration