反应详情

To a cooled (0° C.) solution of 5-iodo-1-methyl-1H-pyrazole (1.3 g, 6.3 mmol) in dimethyl formamide (2 mL), under an atmosphere of nitrogen, was added phosphorus oxychloride (1.72 mL, 18.8 mmol, 3.0 eq.). The resulting mixture was stirred at room temperature for 4 hr before partitioning between ethyl acetate (80 mL) and 2M aqueous potassium carbonate (80 mL). The aqueous layer was extracted again with ethyl acetate (80 mL). The organic extracts were combined and washed with water (3×50 mL) and then dried over magnesium sulphate. The resulting mixture was filtered and the filtrate evaporated under reduced pressure to give the title compound as an orange solid (0.58 g, 39%).

1. custombefore partitioning between ethyl acetate (80 mL) and 2M aqueous potassium carbonate (80 mL)
2. extractionThe aqueous layer was extracted again with ethyl acetate (80 mL)
3. washwashed with water (3×50 mL)
4. dry with materialdried over magnesium sulphate
5. filtrationThe resulting mixture was filtered
6. customthe filtrate evaporated under reduced pressure