Some studies in the chemistry of reactive intermediates

A number of reactions of tetrahalogenobenzynes have been investigated. The reactions of tetrafluorobenzyne with 2-methyl- and 2,5-dimethylfuran gave the expected Diels–Alder adducts (dihydro-tetrafluoroepoxinaphthalene derivatives) which on treatment with butadiene afforded 9-methyl- and 9,10-dimethyltetrahydrotetrafluoroanthracenes. Further reactions with tetrafluorobenzyne followed by dehydrogenation gave 9-methyl- and 9,10-dimethyloctafluorotriptycenes which were used to study new examples of long-range 19F–1H spin–spin coupling 1H NMR spectroscopy. [Continues.]