反应详情

5-bromo-2,4-bis(methyloxy)pyrimidine (commercially available from Aldrich, 500 mg, 2.283 mmol) was dissolved in 1,2-Dimethoxyethane (DME) (5 ml). Pd(Ph3)4 (132 mg, 0.114 mmol) was added and the reaction mixture was stirred at room temperature for 15 min. 1-methyl-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole (commercially available from Maybridge, 997 mg, 4.79 mmol) and 1M/H2O sol. of NaHCO3 (5 ml, 5.00 mmol) were added. After 2 h stirring at 90° C., the reaction mixture was cooled at room temperature, diluted with water (5 ml) and extracted with DCM (3×10 ml). The obtained residue was purified by flash chromatography first eluting with cyclohexane/EtOAc 4:1 then with 1:2 cyclohexane/EtOAc. 483.7 mg of the title compound were obtained.

1. stirringAfter 2 h stirring at 90° C.
2. temperaturethe reaction mixture was cooled at room temperature
3. extractionextracted with DCM (3×10 ml)
4. customThe obtained residue was purified by flash chromatography
5. washfirst eluting with cyclohexane/EtOAc 4:1