4-Fluoroiodobenzene → 1-(4-fluoro-phenyl)-1H-indazole-4-carboxylic acid methyl ester

Participants

Reaction Conditions

Reaction Steps

A mixture of 1H-indazole-4-carboxylic acid methyl ester (5.0 g, 28 mmol), copper iodide (5.7 g, 3.0 mmol), potassium carbonate (4.15 g, 30.0 mmol) and 4-fluoroiodobenzene (3.47 g, 30.0 mmol) is charged in a sealed tube at room temperature. The tube is evacuated, back-filled with argon and dimethylformamide (20 mL) is added followed by rac-trans-N,N′-dimethylcyclohexane-1,2-diamine (0.93 g, 6.5 mmol). The solution is stirred at 120° C. for 3 hours, then cooled to room temperature and diluted with water (50 mL) and ethyl acetate (80 mL). The organic layer is separated, washed with brine (30 mL), and dried over sodium sulfate. The crude product is filtered, concentrated and purified by silica gel chromatography eluting with a gradient of 0-30% ethyl acetate in hexanes to afford 1-(4-fluoro-phenyl)-1H-indazole-4-carboxylic acid methyl ester.

Provenance & Evidence