Remarkable efficiency of the aryne chemistry of (dehydro)octafluoro[2.2]paracyclophane when using the Cadogan method

Generation of the aryne, (dehydro)octafluoro[2.2]paracyclophane, from its acetamide derivative utilizing the Cadogan method led to remarkable results with respect to Diels-Alder and ene reactivity. A comparison was made between this new and virtually unused method and our earlier reported results using Cram methodology (reaction of aryl iodide with potassium tert-butoxide). Surprisingly, no ene reactivity was observed with the Cram methodology. This mechanistic conundrum was examined extensively with no unambiguous explanation for the difference in reactivity being found.