反应详情

温度

110 °C

A solution of potassium permanganate (18.2 g, 115.5 mmol, 2 equiv) in H2O (200 mL) was added to a hot (110° C.) solution of 5-bromo-8-methyl-quinoline (Step 159.4) (12.8 g, 57.7 mmol) in pyridine (120 mL). The reaction mixture was stirred for 10 min at 110° C. and filtered while hot. The residue in the filter was washed with H2O and pyridine. The filtrate was concentrated to remove pyridine, diluted with Et2O and basified by addition of a 2 N aqueous solution of NaOH (20 mL). The aqueous layer was separated and made acidic (pH 3) by addition of a 2 N aqueous solution of HCl. The resulting precipitate was collected by vacuum filtration to provide 1.45 g of the title compound as a green solid: ESI-MS: 251.9/253.9 [M+H]+; tR=3.56 min (System 1).

1. filtrationfiltered while hot
2. washThe residue in the filter was washed with H2O and pyridine
3. concentrationThe filtrate was concentrated
4. customto remove pyridine
5. additiondiluted with Et2O
6. additionbasified by addition of a 2 N aqueous solution of NaOH (20 mL)
7. customThe aqueous layer was separated
8. additionby addition of a 2 N aqueous solution of HCl
9. filtrationThe resulting precipitate was collected by vacuum filtration