反应详情

Ethyl 5-(4,5-dimethoxy-2-nitrobenzoyl)-1H-1,2,3-triazole-4-carboxylate (Synthesis Example 2) (70 mg) and p-toluenesulfonic acid monohydrate (17 mg) were suspended in methylene chloride (10 ml) under an argon atmosphere. Paraformaldehyde (6 mg) was added thereto. The mixture was stirred at room temperature for 30 min. Pyridine (0.05 ml) and ethyl chloroformate (0.04 ml) were added thereto, and the mixture was stirred at room temperature for one hr. Further, pyridine (0.02 ml) and ethyl chloroformate (0.04 ml) were added thereto, and the mixture was stirred for 10 min. The solvent was evaporated under reduced pressure. Ethyl acetate (15 ml) and a saturated aqueous sodium hydrogencarbonate solution (10 ml) were added thereto, followed by separation. The organic layer was washed with a saturated aqueous sodium hydrogencarbonate solution (10 ml) and saturated brine solution (10 ml) in that order and dried over anhydrous magnesium sulfate. The solvent was evaporated under reduced pressure to give ethyl 2-(ethoxycarbonyloxymethyl)-5-(4,5-dimethoxy-2-nitrobenzoyl)-2H-1,2,3-triazole-4-carboxylate as a light yellow foam (48 mg, 53%).

1. stirringthe mixture was stirred at room temperature for one hr
2. stirringthe mixture was stirred for 10 min
3. customThe solvent was evaporated under reduced pressure
4. additionEthyl acetate (15 ml) and a saturated aqueous sodium hydrogencarbonate solution (10 ml) were added
5. customfollowed by separation
6. washThe organic layer was washed with a saturated aqueous sodium hydrogencarbonate solution (10 ml) and saturated brine solution (10 ml) in that order
7. dry with materialdried over anhydrous magnesium sulfate
8. customThe solvent was evaporated under reduced pressure