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 (CH+5), 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 C2H+3, and ethenium C2H+5 are usually classified in other families. The ethanium ion C2H+7 has been studied as an extremely rarefied gas by infrared spectroscopy. [7] The isomers of octonium (protonated octane, C8H+19) 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 ( Ph3PAu)5C+, produced by Schmidbauer and others. [9]
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]
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 (CH+5), 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 C2H+3, and ethenium C2H+5 are usually classified in other families. The ethanium ion C2H+7 has been studied as an extremely rarefied gas by infrared spectroscopy. [7] The isomers of octonium (protonated octane, C8H+19) 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 ( Ph3PAu)5C+, produced by Schmidbauer and others. [9]
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]