Verbesserte Synthese von 7,7-Difluorcyclopropabenzol

Improved Synthesis of 7,7-Difluorocyclopropabenzene A five-step, optimised sequence for the preparation of the title compound is reported. Trichloroethylene is converted to 1,6-dichloro-7,7-difluorobicyclo[4.1.0]hept-3-ene (5) via pentachlorocyclopropane, tetrachlorocyclopropene, and 1,2-dichloro-3,3-difluorocyclopropene by modifications of the procedures reported by Tobey and coworkers. Final dehydrochlorination of 5 allows the production of 7,7-difluorocyclopropabenzene in 50 g quantities.