Dimethyl Sulfate → 7-(2,4-dichloro-phenyl)-2-methyl-2H-indazole

Participants

Reaction Conditions

Reaction Steps

A solution of 7-(2,4-dichloro-phenyl)-1H-indazole (4; 1.12 g, 4.27 mmol) and dimethyl sulfate (0.405 mL, 4.28 mmol) in 15 mL of toluene was stirred at 110° C. for 17 h, allowed to cool, then chilled at 0-5° C. The mixture was carefully washed with 15 mL of a saturated aqueous NaHCO3 solution, dried over MgSO4, filtered (rinsing with diethyl ether), and concentrated to an orange oil Column chromatography (0→33% EtOAc/hexanes) afforded 7-(2,4-dichloro-phenyl)-2-methyl-2H-indazole as a viscous yellow oil (5; 0.92 g, 78%).

Provenance & Evidence