Do high-spin topology rules apply to charged polyradicals? Theoretical and experimental evaluation of pyridiniums as magnetic coupling units

A. P. West, S. K. Silverman, D. A. Dougherty

Research output: Contribution to journalArticle

Abstract

Ab initio calculations on pyridine and pyridinium analogues of m-xylylene indicate that the neutral heterocycle is essentially equivalent to benzene as a ferromagnetic coupling unit, while the cationic pyridiniums behave much differently. Depending on the substitution pattern, a protonated pyridine can serve as a ferromagnetic coupling unit or an antiferromagnetic coupling unit. Both valence bond and molecular orbital arguments provide qualitative rationalizations of these results. In an effort to test the theoretical predictions, bis(trimethylenemethane) analogues of the pyridine and pyridinium biradicals were synthesized and analyzed by electron paramagnetic resonance spectroscopy. General support for the theoretical predictions is obtained.

Original languageEnglish (US)
Pages (from-to)1452-1463
Number of pages12
JournalJournal of the American Chemical Society
Volume118
Issue number6
DOIs
StatePublished - Jan 1 1996

Fingerprint

Magnetic couplings
Pyridine
topology
Topology
rationalization
electron spin resonance
prediction
benzene
substitution
spectroscopy
Molecular orbitals
Benzene
Paramagnetic resonance
Substitution reactions
Spectroscopy
evaluation
pyridine
calculation
test

ASJC Scopus subject areas

  • Catalysis
  • Chemistry(all)
  • Biochemistry
  • Colloid and Surface Chemistry

Cite this

Do high-spin topology rules apply to charged polyradicals? Theoretical and experimental evaluation of pyridiniums as magnetic coupling units. / West, A. P.; Silverman, S. K.; Dougherty, D. A.

In: Journal of the American Chemical Society, Vol. 118, No. 6, 01.01.1996, p. 1452-1463.

Research output: Contribution to journalArticle

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