反应详情

To 3.3 g of 5-amino-7-methoxy-2,2-dimethylchromene there are added 3 g of the compound obtained in Step 3 above, 3.4 g of potassium acetate, 375 mg of Cu(OAc)2.H2O and 120 ml of 2-propanol containing 3.8 ml of triethylamine. The solution is refluxed for 5 days and is then evaporated under reduced pressure. The residue is taken up in a 1/1 mixture of dichloromethane and 1N aqueous HCl solution. After extraction of the aqueous phase, the combined organic phases are treated in customary manner. Chromatography over silica gel (dichloromethane/methanol: gradient from 0.1 to 1%) allows the expected product to be isolated.

1. temperatureThe solution is refluxed for 5 days
2. customis then evaporated under reduced pressure
3. additionThe residue is taken up in a 1/1 mixture of dichloromethane and 1N aqueous HCl solution
4. extractionAfter extraction of the aqueous phase
5. additionthe combined organic phases are treated in customary manner
6. customto be isolated