Synthesis and Properties of 1,1-Dihalogenocyclopropanthracenes

Article abstract of DOI:10.1002/hlca.19820650405

The synthesis of 1,1-difluoro-1H-cyclopropanthracene (3) is described.The key step of the synthesis is the cycloaddition of 1,2-dichloro-3,3-difluorocyclopropene (6) to 2,3-dimethylidene-1,2,3,4-tetrahydronaphthalene (5).The 13C-NMR. spectrum of 3 is assigned on the grounds of C,F-coupling constants, selective H-decoupling and the resulting residual C,H-coupling.The 1,1-dichloro derivative 4 was synthesized by the same route, but could not be isolated pure.Experiments for the reduction to 1H-cyclopropanthracene (2) and for the ionization of 3 or 4 to the cation 16 failed.