Sodium Hydroxide → 7-Bromo-2-methyl-2H-indazole-3-carboxylic acid

Participants

Reaction Conditions

Reaction Steps

A mixture of 7-bromo-2-methyl-2H-indazole-3-carboxylic acid methyl ester (35a; 0.215 g, 0.799 mmol), 8 mL of a 2 M aqueous NaOH solution, and 6 mL of ethanol was stirred at 55° C. overnight, then concentrated to remove ethanol. The remaining aqueous layer was acidified with a 10% aqueous HCl solution and extracted with three 20 mL portions of ethyl acetate. The combined organic layers were dried over Na2SO4, filtered, and concentrated to afford crude 7-bromo-2-methyl-2H-indazole-3-carboxylic acid (35e; 0.193 g; 94%) which was used without further purification.

Provenance & Evidence