4-Bromophenol → 4-Indazol-2-ylphenol

Participants

Reaction Steps

4-Bromophenol (2.00 g, 11.6 mmol) was combined with 1H-indazole (1.64 g, 13.9 mmol), copper(I) iodide (110 mg, 0.578 mmol), potassium phosphate (5.15 g, 24.3 mmol), trans-dimethylcyclohexane-1,2-diamine (0.365 mL, 2.31 mmol), and toluene (10 mL). The reaction was refluxed for 21 hours, then cooled to room temperature and partitioned between ethyl acetate and water/ammonium hydroxide. The organic layer was washed with 0.5 N HCl and brine, dried over magnesium sulfate, filtered and concentrated. Purification by column chromatography (0-40% ethyl acetate in heptane) gave 4-(2H-indazol-2-yl)phenol (0.479 g, 20%) as a tan solid. 1H NMR (400 MHz, (CD3)2SO, δ): 9.84 (s, 1H), 8.90 (s, 1H), 7.86 (d, J=8.8 Hz, 2H), 7.74 (d, J=8.4 Hz, 1H), 7.68 (d, J=8.8 Hz, 1H), 7.22-7.33 (m, 1H), 7.03-7.12 (m, 1H), 6.94 (d, J=8.8 Hz, 2H). MS (M+1): 211.2.

Provenance & Evidence