反应详情

0.7 g (2.7 mmol) of 2,3,4,4-tetrachloro-bicyclo[3.2.2]nona-2,6-diene (known from U.S. Pat. No. 3,538,117) is heated in a mixture of 1 ml of trifluoroacetic acid, 4 ml of acetic acid and 1 ml of water for 18 hours at a temperature of 70° C. The cooled reaction solution is then taken up in diethyl ether and extracted first with water and then with saturated sodium chloride solution. After chromatographic purification (ethyl acetate/hexane 1:4), 0.33 g of 3-chloro-bicyclo-[3.2.2]non-6-ene-2,4-dione is obtained as a tautomeric mixture of the forms Da and Db.

1. customThe cooled reaction solution
2. extractionextracted first with water
3. customAfter chromatographic purification (ethyl acetate/hexane 1:4)