Thermal cyclopropyl-allyl rearrangement of gem-chlorofluorocyclopropanes under gas-phase pyrolysis conditions. Formation of chlorofluoroalkenes and 2-fluorobuta-1,3-dienes

摘要

The gas-phase pyrolysis of isomeric 2-chloro-2-fluoro-1-phenylcyclopropanes in a flow reactor at 250-430 degrees C gives 1-phenyl- and 3-phenyl-3-chloro-2-fluoropropenes. Under similar conditions, methyl-substituted gem-chlorofluorocyclopropanes undergo cyclopropyl-allyl isomerization accompanied by dehydrochlorination to form chlorofluoroalkenes and 2-fluoro-buta-1,3-dienes.