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Updated: Apr 30, 2026

Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Highly selective allylborations of aldehydes using α,α-disubstituted allylic pinacol boronic esters
Matthew J Hesse1, Stéphanie Essafi, Charlotte G Watson
1School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS (UK) http://www.bris.ac.uk/chemistry/research/organic/aggarwal-group.
Abstract:
α,α-Disubstituted allylic pinacol boronic esters undergo highly selective allylborations of aldehydes to give tetrasubstituted homoallylic alcohols with exceptional levels of anti-Z-selectivity (>20:1). The scope of the reaction includes both acyclic and cyclic allylic boronic esters which lead to acyclic and exocyclic tetrasubstituted homoallylic alcohols. The use of β-borylated allylic boronic esters gave fully substituted alkenes bearing a boronic ester which underwent further cross-coupling enabling a highly modular and stereoselective approach to the synthesis of diaryl tetrasubstituted alkenes. Computational analysis revealed the origin of the remarkable selectivity observed.
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