Sodium Carbonate → 7-(2,4-dichloro-phenyl)-1H-indazole

Participants

Reaction Conditions

Reaction Steps

A solution of 7-bromo-1H-indazole (3; 1.01 g, 5.13 mmol) and tetrakis(triphenylphosphine) palladium(0) (0.176 g, 0.152 mmol) in 15 mL of ethylene glycol dimethyl ether was stirred for 30 m. To the solution was added 2,4-dichlorophenyl boronic acid (1.93 g, 10.1 mmol) and a 2 M aqueous Na2CO3 solution (7.1 mL, 14.2 mmol). The orange-yellow mixture was stirred at 80° C. for 19 h, allowed to cool, then partitioned between 50 mL of ethyl acetate and 50 mL of water. The organic layer was dried over MgSO4, filtered, and concentrated to an orange oil. Column chromatography (0→10% EtOAc/hexanes) afforded of 7-(2,4-dichloro-phenyl)-1H-indazole as a pale yellow foamy solid (4; 1.12 g, 83%).

Provenance & Evidence