Selenium Dioxide → 6-Fluoro-8-methoxyquinoline-2-carbaldehyde
Reaction equation
[F:1][C:2]1[CH:3]=[C:4]2[C:9](=[C:10]([O:12][CH3:13])[CH:11]=1)[N:8]=[C:7]([CH3:14])[CH:6]=[CH:5]2.[Se](=O)=[O:16]>O1CCOCC1.O>[F:1][C:2]1[CH:3]=[C:4]2[C:9](=[C:10]([O:12][CH3:13])[CH:11]=1)[N:8]=[C:7]([CH:14]=[O:16])[CH:6]=[CH:5]2Participants
4
Reactant 2
Product 1
Reagents, catalysts & solvents 1
Procedure
To 6-fluoro-8-methoxy-2-methylquinoline (500 mg, 2.62 mmol) in dioxane/water (5 mL/0.5 mL) at ambient temperature was added selenium dioxide (348 mg, 3.14 mmol) and the reaction was heated to reflux for 2-3 hours. After cooling, the reaction was filtered and the solids were washed with DCM. The filtrate was dried over MgSO4, filtered and concentrated under reduced pressure. The residue was purified by reverse phase chromatography (SP4, 25M, eluting with a gradient of water/ACN 100:0 to 0:100, 20 column volumes) to yield 6-fluoro-8-methoxyquinoline-2-carbaldehyde (423 mg, 78.8% yield) as a tan solid.