反应详情

温度

100 °C

A flask containing 7-bromo-2,3-dimethyl-2H-indazole (3.23 g, 14.4 mmol), 2,4,6-trimethylphenyl boronic acid (3.51 g, 21.4 mmol), freshly ground potassium phosphate (6.04 g, 28.5 mmol), 2-dicyclohexylphosphino-2′-(N,N-dimethylamino)biphenyl (0.225 g, 0.572 mmol), and palladium(II) acetate (0.032 g, 0.14 mmol) was evacuated and back-filled with nitrogen. Toluene (50 mL) was added, and the yellow-orange mixture was stirred at 100° C. for 22 h then allowed to cool. Ether (200 mL) was added, and the yellow solution was decanted from a dark granular solid. The organic layer was sequentially washed with 200 mL of a 10% aqueous NaOH solution and 200 mL of a saturated aqueous NaCl solution, dried over MgSO4, filtered, and concentrated to a pale yellow solid. Column chromatography (0→33% EtOAc/hexanes) afforded 2,3-dimethyl-7-(2,4,6-trimethyl-phenyl)-2H-indazole as an off-white solid (7: R=R′=Me, Ar=2,4,6-trimethylphenyl; 3.03 g, 79%; m.p. 162-164).

1. customwas evacuated
2. additionback-filled with nitrogen
3. additionToluene (50 mL) was added
4. temperatureto cool
5. additionEther (200 mL) was added
6. customthe yellow solution was decanted from a dark granular solid
7. washThe organic layer was sequentially washed with 200 mL of a 10% aqueous NaOH solution and 200 mL of a saturated aqueous NaCl solution
8. dry with materialdried over MgSO4
9. filtrationfiltered
10. concentrationconcentrated to a pale yellow solid