FLUORINATION WITH XENON DIFLUORIDE .20. FLUORINATION OF HALO-SUBSTITUTED ALKENES .51. IN A SERIES CHEMISTRY OF ORGANO HALOGENIC MOLECULES

Acid-catalyzed liquid phase fluorine addition with xenon difluoride to 1,1-diphenyl-2-haloethylenes resulted in the formation of vicinal difluorides. trans-α-Fluorostilbene and α,β-difluorostilbene easily reacted with xenon difluoride, thus forming the corresponding trifluoro or tetrafluoro products, cis- and trans-α-chloro- or -bromostilbene were converted with XeF2 to vicinal difluorides. The predominance of syn addition of fluorine over anti addition was observed. In the case of cis- and trans-α-bromostilbene, in addition to vicinal products, the rearranged product 1,1-difluoro-2-bromo-1,2-diphenylethane was formed as well. © 1979 American Chemical Society.