著者

北川 敏一 竹内 賢一 小松 紘一 木下 知己

出版者

The Society of Synthetic Organic Chemistry, Japan

雑誌

有機合成化学協会誌 (ISSN:00379980)

巻号頁・発行日

vol.50, no.8, pp.746-757, 1992-08-01 (Released:2009-11-16)

参考文献数

44

被引用文献数

2 3

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Two novel classes of hydrocarbons, i.e. hydrocarbon salts and ionically dissociative covalent hydrocarbons, were prepared from Kuhn's carbanion (5-) and various cyclopropenylium and tropylium ions.The ionic structures of the hydrocarbon salts were evidenced by IR spectra (solid state), UV-vis spectra (DMSO), and electric conductivity measurements (DMSO) The salt obtained from 5- and tricyclopropylcyclopropenylium ion formed a unique covalent compound in chloroform which can exist only in solution. The salt of 5- and tricyclopropyltropylium ion was found to undergo both coordination and single-electron transfer in THF, affording a yet unknown type of equilibrium system, in which the ionic, radical, and covalent species coexist.Studies on the free energies of heterolysis of the newly synthesized covalent hydrocarbons revealed the importance of the steric effect in the heterolytic cleavage of σ carbon-carbon a bond. It was also found that a slight difference in the cation stability differentiates the product, either ionic or covalent, of the reaction with a carbanion.