8-Hydroxyquinoline → 2-Oxo-1-(4-(trifluoromethoxy)phenyl)-1,2-dihydropyridine-3-carbaldehyde

Participants

Reaction Conditions

Reaction Steps

2-oxo-1,2-dihydropyridine-3-carbaldehyde 1-1 (200 mg, 1.63 mmol), 1-iodo-4-(trifluoromethoxy)benzene 2-1 (562 mg, 1.95 mmol), 8-hydroxyquinoline (47.2 mg, 0.324 mmol), copper iodide (61.9 mg, 0.324 mmol), and potassium carbonate (303 mg, 2.19 mmol) were combined in a round bottom flask with DMSO (3.5 mL) under a nitrogen atmosphere and heated to 130° C. for 21 h. The reaction was cooled to room temperature and poured into a mixture of 10% aq. ammonium hydroxide and ethyl acetate. The resultant mixture was filtered through a pad of Celite and washed with ethyl acetate three times. The layers were separated with the aqueous portion being back extracted with ethyl acetate. The combined organic extracts were washed with brine, dried over Na2SO4, and concentrated in vacuo. Purification by flash column chromatography on silica gel (0-50% EtOAc in hexane) gave 92.0 mg (20%) of 2-2 as an off-white solid: 1H NMR (400 MHz, CDCl3) δ 10.34 (1H, d, J=0.8 Hz), 8.14 (1H, dd, J=6.9, 2.3 Hz), 7.65 (1H, dd, J=6.9, 2.3 Hz), 7.45 (2H, m), 7.38 (2H, m), 6.44 (1H, dt, J=0.8, 6.9 Hz); ESI-MS m/z 284 [C13H8F3NO3+H]+.

Provenance & Evidence