反应详情

85% phosphoric acid (0.18 mL, 1.57 mmol) was added to a solution of ethyl 3-{3-[(tert-butoxycarbonyl)amino]azetidin-1-yl}benzoate obtained in Example (223a) (200 mg, 0.62 mmol) in dichloromethane (0.8 mL) at room temperature, followed by stirring for 27 hours. Water and a 50% aqueous sodium hydroxide solution were added to the reaction solution, and then the mixture was extracted with chloroform. The combined organic layers were dried over anhydrous magnesium sulfate and filtered. Thereafter, the solvent was evaporated under reduced pressure to obtain 114 mg of the title compound as a colorless oily substance (83%).

1. extractionthe mixture was extracted with chloroform
2. dry with materialThe combined organic layers were dried over anhydrous magnesium sulfate
3. filtrationfiltered
4. customThereafter, the solvent was evaporated under reduced pressure