TM5441

1190222-68-4

1190221-43-2

GENERAL METHOD: Ester compound 12a (0.46 g, 1.17 mmol) was dissolved in tetrahydrofuran (4.6 mL) and 1 N aqueous sodium hydroxide solution (1.29 mL) was added. The reaction mixture was stirred at 50 °C for 3 hours. After completion of the reaction, it was cooled to room temperature and the tetrahydrofuran was removed by distillation under reduced pressure. The residue was acidified with 1 N hydrochloric acid and the resulting precipitate was collected by filtration. The precipitate was washed sequentially with water and isopropyl ether and dried under vacuum to afford the target carboxylic acid compound 24 as a solid (0.425 g, 96% yield).