反应详情

A mixture of 12.53 g of 3,4-dihydro-2-(2-bromoethyl)-2,5,7,8-tetramethyl-2H-1-benzopyran-6-ol and liquid dimethylamine in 50 ml of dimethylformamide is stirred at room temperature for 16 hours. Water is added and the product is extracted with ethyl ether. The extract is washed with water, dried over anhydrous sodium sulfate, filtered and evaporated. One equivalent of hydrochloride acid in isopropanol is added and the resulting precipitate is recrystallized twice from isopropanol/water to yield 9.44 g of the title compound, m.p. >300° C.

1. extractionthe product is extracted with ethyl ether
2. washThe extract is washed with water
3. dry with materialdried over anhydrous sodium sulfate
4. filtrationfiltered
5. customevaporated
6. customthe resulting precipitate is recrystallized twice from isopropanol/water