反应详情

The crude [4-(3,5-bis(4-trifluoromethylphenyl)-benzyloxy)-2-methyl-phenoxy]-acetic acid methyl ester from Step A above is dissolved in dioxane (2 mL). Solid lithium hydroxide monohydrate (18 mg, 0.44 mmol, excess) is added, followed by water (0.2 mL). After 1 hour, the mixture is concentrated to dryness. Purification by reversed-phase HPLC yields [4-(3,5-bis(4-trifluoromethylphenyl)-benzyloxy)-2-methyl-phenoxy]-acetic acid A1 as a solid. 1H-NMR (400 MHz, CDCl3) δ=7.67 (m, 9H), 7.61 (s, 2H), 6.82 (d, J=2.8 Hz, 1H), 6.72 (dd, J=9.0, 2.8 Hz, 1H), 6.64 (d, J=9.2 Hz, 1H), 5.08 (s, 2H), 4.58 (s, 2H), 2.22 (s, 3H). 19F-NMR (376 MHz, CDCl3) δ=−62.4. No MS could be obtained.

1. concentrationthe mixture is concentrated to dryness
2. customPurification by reversed-phase