Into a dry reaction vessel, ethyl 2-[3-[4-(4-chlorobenzamido)benzyl]-2-methyl-1H-indol-1-yl]acetate (580 mg, 1.26 mmol), lithium hydroxide monohydrate (159 mg, 3.79 mmol), 10 mL tetrahydrofuran, 10 mL methanol, 10 mL water were weighed, and stirred at room temperature for 1 h. The reaction was monitored to be complete by TLC. The solvent was rotate evaporated. It was adjusted to pH=3-4 with 2 N HCl solution. It was filtered, and the filter cake was washed with 20 mL methanol to obtain the product as a white solid 523 mg, at a yield of 95.9%.
