The application of known methodology has provided 2,3-dimethylidene-2,3-dihydro-1,4-benzodioxin (12) as the essential precursor for preparation of the cyclopropa-fused dibenzodioxin 3,8-dioxa-1H-cyclopropa [b] anthracene (14). Cycloproparene (14) is both unstable and acid-sensitive, and readily dimerizes to a mixture of the dihydrotetraoxaheptacene (15) and its heptaphene analogue (16).
已知方法论的应用提供了2,3-二甲基亚甲基-2,3-二氢-1,4-苯并二氧杂环戊二烯(12)作为制备环丙烷融合二苯并二氧杂环戊烷3,8-二氧-1H-环丙[b]蒽(14)的必要前体。环丙烯(14)既不稳定又对酸敏感,并且容易二聚形成二氢四氧七环芳烃(15)及其七苯类似物(16)的混合物。