Triphenylphosphine → Ethyl 6-(4-hydroxyphenyl)-2-quinolinecarboxylate

Participants

Reaction Conditions

Reaction Steps

Palladium(II)acetate (17.1 mg, 76.0 μmol) was added to ethyl 6-bromo-2-quinolinecarboxylate (426.0 mg, 1.52 mmol, from Example 32c), 4-hydroxy-phenyl-boronic acid (314.6 mg, 2.28 mmol), triphenylphosphine (39.9 mg, 152.1 μmol), and potassium phosphate (1.13 g, 5.32 mmol). Then, dioxane (7.6 mL) was added to the mixture, followed by water (152 μL), and the reaction mixture was heated open to the atmosphere at 60° C. in an oil bath for 16 hours, then allowed to cool to room temperature. Water was added followed by ethyl acetate and the mixture was filtered through Celite®. The filtrate was extracted with ethyl acetate and the organic layer was dried over anhydrous magnesium sulfate, then filtered and concentrated. The residue was purified by silica gel chromatography eluting with 2:3 ethyl acetate:hexanes to give 260.5 mg (58%) of ethyl 6-(4-hydroxyphenyl)-2-quinolinecarboxylate as a solid. 1H NMR (400 MHz, d6-DMSO): δ 9.74 (s, 1H), 8.55 (d, J=9 Hz, 1H), 8.28 (s, 1H), 8.19-8.10 (m, 3H), 7.72 (d, J=9 Hz, 2H), 6.92 (d, J=9 Hz, 2H), 4.42 (q, J=7 Hz, 2H), 1.38 (t, J=7 Hz, 3H). ESI-LCMS m/z 294 (M+H)+.

Provenance & Evidence