反应详情

A solution of 2-bromo-5-methoxy-3-methyl-phenylamine ((Example 198: step c) 2.04 g, 6.18 mmol) in dry dioxane (100 mL) was treated with triethylamine (5.26 mL, 37.7 mmol), 2-(dicyclohexylphosphino)biphenyl (0.662 g, 1.89 mmol), and Pd(OAc)2 (0.106 g, 0.472 mmol). 4,4,5,5-Tetramethyl-1,3,2-dioxaborolane (4.09 mL, 28.3 mmol) was added slowly and the mixture heated to reflux for 1 h. The dioxane was evaporated in vacuo. The residue was taken up in EtOAc and washed with water (2×75 mL). The organic layer was filtered by gravity to remove the palladium residue, dried over MgSO4 and concentrated in vacuo. Silica gel chromatography (10–25% EtOAc in hexanes raised in 5% increments) afforded the product 5-methoxy-3-methyl-2-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-phenylamine (1.61 g, 98%) as a light brown solid. 1H NMR (CDCl3): δ 7.361 (d, 1H, J=7.6 Hz), 7.279 (d, 1H, J=8.0 Hz), 3.815 (s, 3H), 2.46 (s, 3H), 1.356 (s, 12H).

1. temperaturethe mixture heated
2. temperatureto reflux for 1 h
3. customThe dioxane was evaporated in vacuo
4. washwashed with water (2×75 mL)
5. filtrationThe organic layer was filtered by gravity
6. customto remove the palladium residue
7. dry with materialdried over MgSO4
8. concentrationconcentrated in vacuo
9. temperatureSilica gel chromatography (10–25% EtOAc in hexanes raised in 5% increments)