117341-97-6Relevant academic research and scientific papers
NON-KEKULE MOLECULES DERIVED CONCEPTUALLY BY HETEROATOM-FOR-CARBON SUBSTITUTION IN ALTERNANT HYDROCARBONS; M-QUINOMETHANE AND M-NAPHTHOQUINOMETHANE
Rule, Mark,Matlin, Albert R.,Seeger, David E.,Hilinski, Edwin F.,Dougherty, Dennis A.,Berson, Jerome A.
, p. 787 - 798 (1982)
Qualitative theoretical considerations suggest that substitution of a heteroatom for a C atom in an alternant hydrocarbon might result in a non-Kekule molecule with a triplet ground state, despite the non-degeneracy of the Hueckel NBMOs of the heteroatom derivative.The syntheses of 3-methylene-1-phenoxyl and 3-methylene-1-naphthoxyl are described.These compounds, biradical valence tautomers of m-quinomethanes, are characterized by EPR spectroscopy and are assigned triplet ground states.Optical resolution of 6-methylene-bicyclohex-3-ene-2-one, the precursor of 3-methylene-1-phenoxyl, is described.Repeated irradiation of the active ketone at 20K with intermittent warming to room temperature followed by re-isolation gives ketone of undiminished activity, which suggests that re-cyclization of (presumably achiral) 3-methylene-1-phenoxyl does not occur under these conditions.
