The Michael Reaction of Fluoro-substituted-9,9′-Bifluorenylidenes and -Fluorenes, and the Syntheses of Some Related Compounds

The Michael reaction of fluoro-substituted 9,9′-bifluorenylidenes and fluorenes was carried out; the normal addition products, fluoro-substituted tribiphenylenepropanes, were obtained, but no abnormal product was isolated. Some new fluoro-substituted-fluorenes, -9,9′-bifluorenylidenes, -9,9′-bifluorenyls and -α,δ-dibiphenylenebutadienes, were synthesized. The structures of the fluoro-substituted tribiphenylenepropanes were confirmed by the lithium-halogen interconversion reaction of 9-lithiofluorenes and 9-bromo-9,9′-bifluorenyls. The pyrolyses of fluoro-substituted tribiphenylenepropanes afforded fluoro-substituted or nonfluoro-substituted-9,9′-bifluorenylidenes, -9,9′-bifluorenyls, -fluorenes, and -fluorenones. Differential scanning calorimetry was applied to fluoro-substituted-9,9′-bifluorenyls and -tribiphenylenepropanes.