反应详情

A mixture of 3.81 g (25 mM) of 4-n-propylcatechol, 5.06 g (50 mM) of triethylamine and 50 ml of dry ether was cooled in an ice water bath so as to maintain the temperature at 5° C. or below. The mixture was added dropwise over 1.5 hours under stirring with a solution of 3.50 g (28 mM) of oxalyl chloride in 10 ml of dry ether. After completing the dropwise addition, the temperature of the reaction mixture was gradually raised to the room temperature and then aging was conducted for an hour. The resultant mixture was heated under reflux for 3 hours in order to complete the aging. The separated crystals of triethyl ammonium chloride was filtered. After thoroughly washing the crystals with ether, the ether solution was collected and dried with anhydrous sodium sulfate. After distilling off ether, the reaction product was recrystallized from a solvent mixture of carbontetrachloride and petroleum benzine to obtain 4.64 g (22.5 mM) of 6-n-propyl-1,4-benzodioxine-2,3-dione monohydrate as colorless crystals having a melting point of 99°-100° C.

1. temperaturewas cooled in an ice water bath so as
2. temperatureto maintain the temperature at 5° C. or below
3. additionThe mixture was added dropwise over 1.5 hours
4. additionthe dropwise addition
5. waitaging was conducted for an hour
6. temperatureunder reflux for 3 hours in order
7. filtrationThe separated crystals of triethyl ammonium chloride was filtered
8. washAfter thoroughly washing the crystals with ether
9. customthe ether solution was collected
10. dry with materialdried with anhydrous sodium sulfate
11. distillationAfter distilling off ether
12. customthe reaction product was recrystallized from a solvent mixture of carbontetrachloride and petroleum benzine