Английская Википедия:Carbonium ion

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Шаблон:Short description In chemistry, a carbonium ion is any cation that has a pentacoordinated carbon atom.[1][2] The name carbonium may also be used for the simplest member of the class, properly called methanium (Шаблон:Chem2), where the carbon atom is covalently bonded to five hydrogen atoms.[3][4][5][6]

The next simplest carbonium ions after methanium have two carbon atoms. Ethynium, or protonated acetylene Шаблон:Chem2, and ethenium Шаблон:Chem2 are usually classified in other families. The ethanium ion Шаблон:Chem2 has been studied as an extremely rarefied gas by infrared spectroscopy.[7] The isomers of octonium (protonated octane, Шаблон:Chem2) have been studied.[8] The carbonium ion has a planar geometry.

In older literature, the name "carbonium ion" was used for what is today called carbenium. The current definitions were proposed by the chemist George Andrew Olah in 1972[1] and are now widely accepted.

A stable carbonium ion is the complex pentakis(triphenylphosphinegold(I))methanium Шаблон:Chem2, produced by Schmidbauer and others.[9]

Preparation

Carbonium ions can be obtained by treating alkanes with very strong acids.[10] Industrially, they are formed in the refining of petroleum during primary thermal cracking (Haag-Dessau mechanism).[11][12]

See also

References

Шаблон:Reflist