Hofmann decomposition of quaternary ammonium salts under phase-transfer catalytic conditions

Jaime De La Zerda, Ronny Neumann, Yoel Sasson

Research output: Contribution to journalArticle

21 Citations (Scopus)

Abstract

The known Hofmann degradation of quaternary ammonium salts under basic phase-transfer catalytic conditions has been studied. The base-catalysed isomerization of p-allylanisole to p-methoxy-β-methylstyrene was used as a kinetic probe to find experimentally the rate constant and activation energy of the Hofmann decomposition without isolating the quaternary ammonium basic salt R4N+B-(B-=base anion). Reactions performed at various temperatures showed that the higher the temperature the greater was the initial rate but the lower the final conversion in the isomerization reaction. The quaternary ammonium hydroxide was found to catalyse the isomerization and the Hofmann degradation more effectively than the corresponding alkoxide. This indicates that the former is a stronger base in the nonpolar aprotic solvents common in phase-transfer catalysis.

Original languageEnglish
Pages (from-to)823-826
Number of pages4
JournalJournal of the Chemical Society, Perkin Transactions 2
Issue number6
DOIs
Publication statusPublished - 1986

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Isomerization
Ammonium Compounds
Salts
Decomposition
Ammonium Hydroxide
Degradation
Catalysis
Anions
Rate constants
Activation energy
Temperature
Kinetics

ASJC Scopus subject areas

  • Chemistry(all)

Cite this

Hofmann decomposition of quaternary ammonium salts under phase-transfer catalytic conditions. / De La Zerda, Jaime; Neumann, Ronny; Sasson, Yoel.

In: Journal of the Chemical Society, Perkin Transactions 2, No. 6, 1986, p. 823-826.

Research output: Contribution to journalArticle

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