反应详情

3.8 g (16.4 mmol) of 2,3-dichloro-5,6-dicyano-p-benzoquinone are added to a solution of 6.6 g (16.4 mmol) of the compound from Example 2 in 200 ml of methylene chloride p.a. and the mixture is stirred for 1 h at room temperature. It is then filtered over kieselgur with suction, the methylene chloride phase is extracted three times using 100 ml of water each time and dried over magnesium sulphate. After concentrating in vacuo, the residue is chromatographed on a column (100 g of silica gel 70-230 mesh, φ3.5 cm, using ethyl acetate/petroleum ether (1:9).

1. filtrationIt is then filtered over kieselgur with suction
2. extractionthe methylene chloride phase is extracted three times
3. dry with materialdried over magnesium sulphate
4. concentrationAfter concentrating in vacuo
5. customthe residue is chromatographed on a column (100 g of silica gel 70-230 mesh, φ3