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Updated: Dec 24, 2025
Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Rhodium(III)-Catalyzed Atroposelective Synthesis of Biaryls by C-H Activation and Intermolecular Coupling with
Fen Wang1, Zisong Qi1, Yuxia Zhao1
1School of Chemistry and Chemical Engineering, Shaanxi Normal University (SNNU), Xi'an, 710062, China.
Abstract:
Reported herein is the atroposelective synthesis of biaryl NH isoquinolones by RhIII -catalyzed C-H activation of benzamides and intermolecular [4+2] annulation for a broad scope of 2-substituted 1-alkynylnaphthalenes, as well as sterically hindered, symmetric diarylacetylenes. The axial chirality is constructed based on dynamic kinetic transformation of the alkyne in redox-neutral annulation with benzamides, with alkyne insertion being stereodetermining. The reaction accommodates both benzamides and heteroaryl carboxamides and proceeds in excellent regioselectivity (if applicable) and enantioselectivities (average 91.8 % ee). An enantiomerically and diastereomerically pure rhodacyclic complex was prepared and offers insight into enantiomeric control of the coupling system, wherein the steric interactions between the amide directing group and the alkyne substrate dictate both the regio- and enantioselectivity.
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