反应详情

A solution of 8.0 g (33.7 mmol) of 5,6-difluoro-2-methylquinoline-8-carboxylic acid methyl ester (Example 33) in 100 mL of glacial acetic acid is treated with 2.15 g of platinum on carbon (0.8 g of active catalyst+62.8% water) and then shaken in a hydrogen atmosphere at temperatures of 24° C. to 29° C. and pressures of 23.9 to 46.6 psi for 3 hours. The catalyst is removed by filtration and the solvent is removed in vacuo at 50° C. The residue is triturated with water (50 mL) and extracted with dichloromethane (2×200 mL). The combined organic layers are stirred with 5% sodium bicarbonate solution, washed with water, dried (MgSO4), filtered and evaporated in vacuo. The residue is chromatographed over flash grade silica gel (230–400 mesh) eluting with dichloromethane to give 5.6 g of the title compound as a light yellow oil. 1H NMR (400 MHz, CDCl3): 7.66 (bs, 1H), 7.49 (m, 1H), 3.82 (s, 3H), 3.46 (m, 1H), 2.88 (m, 1H), 2.67 (m, 1H), 1.97 (m, 1H), 1.27 (d, 3H).

1. customThe catalyst is removed by filtration
2. customthe solvent is removed in vacuo at 50° C
3. customThe residue is triturated with water (50 mL)
4. extractionextracted with dichloromethane (2×200 mL)
5. washwashed with water
6. dry with materialdried (MgSO4)
7. filtrationfiltered
8. customevaporated in vacuo
9. customThe residue is chromatographed over flash grade silica gel (230–400 mesh)
10. washeluting with dichloromethane