Conformational analysis of triarylboranes

John F. Blount, Paolo Finocchiaro, John Devens Gust, Kurt Mislow

Research output: Contribution to journalArticle

134 Citations (Scopus)

Abstract

An X-ray structure determination shows that trimesitylborane assumes a propeller conformation in the crystal lattice. The low-temperature 1H-nmr spectra of diverse triarylboranes which have substituents other than hydrogen in all six ortho positions are consistent with this geometry in solution. At higher temperatures, the spectra reflect rapid stereoisomerizations, which are interpreted in terms of two-ring flip mechanisms. These processes have activation energies of ca. 14-16 kcal/mol, and separation of stereoisomers at ambient temperatures is therefore precluded.

Original languageEnglish
Pages (from-to)7019-7029
Number of pages11
JournalJournal of the American Chemical Society
Volume95
Issue number21
Publication statusPublished - 1973

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Temperature
Stereoisomerism
Propellers
Crystal lattices
Conformations
Hydrogen
Activation energy
X-Rays
X rays
Geometry

ASJC Scopus subject areas

  • Chemistry(all)

Cite this

Blount, J. F., Finocchiaro, P., Gust, J. D., & Mislow, K. (1973). Conformational analysis of triarylboranes. Journal of the American Chemical Society, 95(21), 7019-7029.

Conformational analysis of triarylboranes. / Blount, John F.; Finocchiaro, Paolo; Gust, John Devens; Mislow, Kurt.

In: Journal of the American Chemical Society, Vol. 95, No. 21, 1973, p. 7019-7029.

Research output: Contribution to journalArticle

Blount, JF, Finocchiaro, P, Gust, JD & Mislow, K 1973, 'Conformational analysis of triarylboranes', Journal of the American Chemical Society, vol. 95, no. 21, pp. 7019-7029.
Blount JF, Finocchiaro P, Gust JD, Mislow K. Conformational analysis of triarylboranes. Journal of the American Chemical Society. 1973;95(21):7019-7029.
Blount, John F. ; Finocchiaro, Paolo ; Gust, John Devens ; Mislow, Kurt. / Conformational analysis of triarylboranes. In: Journal of the American Chemical Society. 1973 ; Vol. 95, No. 21. pp. 7019-7029.
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