Fluorinated acetylenes. Part 13. Synthesis of 1,6-diphenyl-3,3,4,4-tetrafluorohexa-1,5-diyne

Article abstract of DOI:10.1016/S0022-1139(00)80063-9

The title compound (6) may be conveniently synthesised via the three-stage route: .In the first stage the alkyne PhCCBr is also produced, and this undergoes reaction with iodine generated in the second stage to give the alkene (E)-PhCI=CBrI (10) (up to 9.5percent).Other by-products formed in the second stage, depending on the conditions employed, are the 1,4-diyne PhCCCF2CCPh (12), isolated in 3,5percent yield, and 1-iodo-2,3-naphtho-4-phenyltetrafluorocyclobutene (11), isolated in 11.5percent yield.Mechanisms are advanced to account for all the products isolated.