反应详情

A solution of 1a (3.0 g, 11.24 mmol) in benzene (100 mL) was mixed with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (3.8 g, 16.85 mmol). The resultant mixture was heated at reflux for 2 h, diluted with saturated NaHCO3 solution (300 mL) and extracted with ethyl acetate (300 mL, 3×). The combined organic phases were dried over MgSO4, filtered, and concentrated. Flash chromatography (hexanes/ethyl acetate, 8:1) then provided the title compound (1.06 g, 35%) as a yellow solid: MS (ES) m/z 264 (M+H)+;

1. temperatureat reflux for 2 h
2. extractionextracted with ethyl acetate (300 mL, 3×)
3. dry with materialThe combined organic phases were dried over MgSO4
4. filtrationfiltered
5. concentrationconcentrated