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Updated: Feb 7, 2026

Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Formation of borata-alkene/iminium zwitterions by ynamine hydroboration
Long Wang1, Zhongbao Jian, Constantin G Daniliuc
1Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstr. 40, 48149 Münster, Germany. erker@uni-muenster.de.
Abstract:
The ynamine TMP-C[triple bond, length as m-dash]C-CH3 adds HB(C6F5)2 to give the unsaturated C2-bridged N/B FLP 5. Compound 5 shows the structural data indicating a marked participation of the zwitterionic mesomeric borata-alkene/iminium form. It splits dihydrogen at r.t. with Z- to E-isomerization at the central C[double bond, length as m-dash]C double bond. Hydroboration of the ynamine Me3Si-C[triple bond, length as m-dash]C-NiPr2 with HB(C6F5)2 yields a N/B FLP that shows a strongly distorted central C[double bond, length as m-dash]C double bond with a rotation of the planes of the substituent pairs at its ends by ca. 57°.
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