Novel Annelation Reaction: Synthesis of Polycyclic Hydrocarbons from o-Quinones

Article abstract of DOI:10.1021/jo00326a028

A novel general synthesis of polycyclic aromatic ring systems involving initial reaction of polycyclic o-quinone with lithium acetylide, reduction of the resulting diacetylenic diol with LiAlH4 to the corresponding divinyl diol, and finally cyclization and dehydration with HI or POCl3 to a polyarene having one more aromatic ring is reported.Syntheses of triphenylene, dibenzanthracene, benzopyrene, and benzochrysene by this means from phenanthrene-9,10-dione, benzanthracene-5,6-dione, pyrene-4,5-dione, and chrysene-5,6-dione, respectively, are described.Yields are high (94-97percent) in the initial two steps and good (52-74percent) in the final stage.The divinyl diol intermediates may be generated directly, though in lower yield, via direct reaction of the quinones with vinylmagnesium bromide or vinyllithium reagents.Various related reactions are also explored, and evidence concerning the stereochemistries of the intermediates and the mechanisms of these reactions is discussed.