Conformational dynamics of alkoxydiarylboranes

Paolo Finocchiaro, John Devens Gust, Kurt Mislow

Research output: Contribution to journalArticle

55 Citations (Scopus)

Abstract

The low-temperature 1H-nmr spectra of several alkoxydiarylboranes are shown to be consistent with three alternatives: the molecules adopt propeller conformations, and stereoisomerization is slow on the nmr time scale; the molecules adopt propeller conformations with rapid stereoisomerization by means of one-flip pathways; the molecules adopt perpendicular conformations with slow stereoisomerization. Stereoisomerization phenomena observed at elevated temperatures are discussed in terms of flip mechanisms, and pathways which involve the flipping of aryl groups only are found to have lower activation energies than those which also involve flipping of the alkoxy group. An analysis of the isomerization processes reveals restricted rotation about the B-O bond, and arguments are presented which suggest that conjugative effects between boron and oxygen play a significant role in the stereochemistry of alkoxyarylboranes.

Original languageEnglish
Pages (from-to)7029-7036
Number of pages8
JournalJournal of the American Chemical Society
Volume95
Issue number21
Publication statusPublished - 1973

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Conformations
Propellers
Molecules
Temperature
Boron
Stereochemistry
Oxygen
Isomerization
Activation energy
alkoxyl radical

ASJC Scopus subject areas

  • Chemistry(all)

Cite this

Conformational dynamics of alkoxydiarylboranes. / Finocchiaro, Paolo; Gust, John Devens; Mislow, Kurt.

In: Journal of the American Chemical Society, Vol. 95, No. 21, 1973, p. 7029-7036.

Research output: Contribution to journalArticle

Finocchiaro, P, Gust, JD & Mislow, K 1973, 'Conformational dynamics of alkoxydiarylboranes', Journal of the American Chemical Society, vol. 95, no. 21, pp. 7029-7036.
Finocchiaro, Paolo ; Gust, John Devens ; Mislow, Kurt. / Conformational dynamics of alkoxydiarylboranes. In: Journal of the American Chemical Society. 1973 ; Vol. 95, No. 21. pp. 7029-7036.
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