反应详情

To a solution of methyl 3-bromo-5-(trifluoromethyl)benzoate (21.8 g, 77 mmol) in 1,4-dioxane (218 mL), and water (131 mL) were added 1-methyl-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole (24 g, 116 mmol), sodium carbonate (27.7 g, 261 mmol) and tetrakis(triphenyphosphine)palladium(0) (4.4 g, 3.8 mmol). The reaction mixture was heated at 80° C. for 3 h after which time TLC (20% EtOAc/hexane) showed consumption of the starting material. The reaction mixture was cooled to room temperature and precipitated solids were removed by filtration. The filtrate was diluted with water and extracted twice with ethyl acetate. The extracts were washed with brine, dried over sodium sulfate, filtered and concentrated. The residue was purified by filtration through silica, eluting with 0% to 40% ethyl acetate in hexanes to provide methyl 3-(1-methyl-1H-pyrazol-4-yl)-5-(trifluoromethyl)benzoate as a pale yellow solid (22.3 g, 100%). LC-MS (FA): ES+ 285; 1H NMR (400 MHz, CDCl3) δ ppm 8.29 (s, 1H), 8.14 (s, 1H), 7.87 (s, 1H), 7.86 (s, 1H), 7.76 (s, 1H), 4.01 (s, 3H), 3.98 (s, 3H).

1. customconsumption of the starting material
2. customprecipitated solids
3. customwere removed by filtration
4. additionThe filtrate was diluted with water
5. extractionextracted twice with ethyl acetate
6. washThe extracts were washed with brine
7. dry with materialdried over sodium sulfate
8. filtrationfiltered
9. concentrationconcentrated
10. filtrationThe residue was purified by filtration through silica
11. washeluting with 0% to 40% ethyl acetate in hexanes