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quaternary ammonium compound
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Ammonia and amines have a slightly flattened trigonal pyramidal shape, with a lone pair of electrons above the nitrogen. In quaternary ammonium salts, this area is occupied by a fourth substituent. Rapid inversion takes place between the enantiomers of amines with chiral nitrogens, but in quaternary ammonium ions such interconversion is not possible.
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quaternary ammonium compound

chemical compound
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Ammonia and amines have a slightly flattened trigonal pyramidal shape, with a lone pair of electrons above the nitrogen. In quaternary ammonium salts, this area is occupied by a fourth substituent. Rapid inversion takes place between the enantiomers of amines with chiral nitrogens, but in quaternary ammonium ions such interconversion is not possible.
Ammonia and amines have a slightly flattened trigonal pyramidal shape, with a lone pair of electrons above the nitrogen. In quaternary ammonium salts, this area is occupied by a fourth substituent. Rapid inversion takes place between the enantiomers of amines with chiral nitrogens, but in quaternary ammonium ions such interconversion is not possible.

Quaternary ammonium compounds are a class of strong bases and their salts derived from ammonium. In these compounds, the hydrogen atoms of ammonium are replaced by organic radicals. They are significant for their roles as surface-active agents, disinfectants, and in pharmaceuticals.1

Amines, from which quaternary ammonium compounds are derived, are organic compounds containing nitrogen, based on ammonia. They are categorized as primary, secondary, or tertiary depending on the number of organic groups attached to the nitrogen atom. Quaternary ammonium compounds represent a fourth category, where all four hydrogen atoms of the ammonium ion are replaced by organic groups, requiring an associated anion (R₄N⁺X⁻). A key reaction of quaternary ammonium compounds is the Hofmann degradation, where heating their hydroxides produces a tertiary amine and an alkene.23

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3 Britannica Sources
  1. quaternary ammonium compound
  2. amine
  3. amine - Elimination

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