反应详情

[4-(3,5-Dibromo-benzyloxy)-2-methyl-phenoxy]-acetic acid methyl ester 13 (0.0375 g, 0.088 mmol) is dissolved in dioxane (1 mL). 4-Trifluoromethyl-phenylboronic acid (0.0514 g, 0.27 mmol) is added, followed by water (0.01 mL), ethanol (0.01 mL), potassium carbonate (0.0557 g, 0.4 mmol), and tetrakis-(triphenylphosphino)palladium (0.117 g, 0.01 mmol). The mixture is stirred under nitrogen and subjected to microwave (170° C. for 10 min). The resulting orange suspension is filtered, the solids are washed with more dioxane, and the resulting solution is concentrated and purified by silica gel chromatography (10% to 25% ethyl acetate in hexanes) to yield [4-(3,5-bis(4-trifluoromethylphenyl)-benzyloxy)-2-methyl-phenoxy]-acetic acid methyl ester as an oil. 1H-NMR (400 MHz, CDCl3) δ=7.77-7.64 (m, 8H), 7.52 (s, 2H), 7.34 (s, 1H), 6.88 (d, J=2.8 Hz, 1H), 6.76 (dd, J=9.0, 2.8 Hz, 1H), 6.68 (d, J=9.2 Hz, 1H), 5.14 (s, 2H), 4.61 (s, 2H), 3.80 (s, 3H), 2.95 (s, 3H). 19F-NMR (376 MHz, CDCl3) δ=−62.4.

1. custom(170° C. for 10 min)
2. filtrationThe resulting orange suspension is filtered
3. washthe solids are washed with more dioxane
4. concentrationthe resulting solution is concentrated
5. custompurified by silica gel chromatography (10% to 25% ethyl acetate in hexanes)