Trimethylsilyl ethers of 1,5-diaryl-3-(trifluoromethyl)pent-1-en-4-yn-3-oles in superacid CF ₃SO ₃H (TfOH) give rise to the corresponding intermediate CF ₃-pentenynyl cations. These species react with benzene to afford conjugated CF ₃-pentenynes, which undergo subsequent cyclization, first, into CF ₃-cycloheptadienes and, finally, into unusual CF ₃-"helicopter"-like bicyclic structures.