Dynamic stereochemistry of hexaarylbenzenes

John Devens Gust, Alan Patton

Research output: Contribution to journalArticle

60 Citations (Scopus)

Abstract

Rotational isomerism in hexaarylbenzenes has been analyzed mathematically and studied experimentally. The mathematical analysis demonstrates that 13 rearrangement modes are possible for such molecules. The isomerization pathway actually followed is revealed by experimental studies of highly substituted hexa- and pentaarylbenzenes, one of which gives rise to 16 rotational stereoisomers. Kinetic studies using both NMR and classical methods strongly support a mechanism wherein one peripheral aryl ring at a time rotates by ∼π radians. Measured free energies of activation for isomerization vary from about 33 kcal/mol for rotations of rings bearing an ortho methoxy group to about 17 kcal/mol for rotations of rings bearing meta substituents.

Original languageEnglish
Pages (from-to)8175-8181
Number of pages7
JournalJournal of the American Chemical Society
Volume100
Issue number26
Publication statusPublished - 1978

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Bearings (structural)
Stereochemistry
Isomerization
Isomerism
Stereoisomerism
Free energy
Chemical activation
Nuclear magnetic resonance
Molecules
Kinetics

ASJC Scopus subject areas

  • Chemistry(all)

Cite this

Dynamic stereochemistry of hexaarylbenzenes. / Gust, John Devens; Patton, Alan.

In: Journal of the American Chemical Society, Vol. 100, No. 26, 1978, p. 8175-8181.

Research output: Contribution to journalArticle

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