2,4-Dichloro-5-(2,4,6-trimethoxyphenyl)cyclopent-4-ene-1,3-dione derivatives in the reaction with CrCl2

The reactions of 2,4-dichloro-5-(2,4,6-trimethoxyphenyl)cyclopent-4-ene-1,3-dione and its 2-allyl derivative with CrCl2 were studied. Both reactions are accompanied by the saturation of the cyclopentenone double bond and the simultaneous reductive dechlorination of chlorine-containing centers. The structure of the final allyl-containing product was determined by X-ray diffraction.