Cesium carbonate → 3-(3,5-Difluorophenoxy)-5-(1,3-dioxolan-2-yl)-1-{[2-(trimethylsilyl)ethoxy]methyl}-1H-indazole

Participants

Reaction Conditions

Reaction Steps

To a microwave-flask containing 300 mg (0.672 mmol) 5-(1,3-dioxolan-2-yl)-3-iodo-1-{[2-(trimethylsilyl)ethoxy]methyl}-1H-indazole (Example 6A), 438 mg (1.344 mmol) cesium carbonate and 19 mg (0.134 mmol) N,N-dimethylglycine hydrochloride in 1,4-dioxane (3 ml) were added 131 mg (1.008 mmol) 3,5-difluorophenol and 13 mg (0.067 mmol) copper(I) iodide. The flask was placed in an ultrasonic bath, and argon was bubbled through for a period of five minutes. The flask was then sealed and heated to 140° C. for 2 h using microwave irradiation. After this time, the same amounts of N,N-dimethylglycine hydrochloride and copper(I) iodide were added again, and heating was continued for further 2 h. This procedure was repeated one more time. Then, the reaction mixture was filtered, and the filtrate was purified by preparative RP-HPLC (acetonitrile/water+0.05% TFA gradient) to afford 43 mg (14% of th.) of the title compound.

Provenance & Evidence