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Updated: Dec 25, 2025
Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
A Transient-Directing-Group Strategy Enables Enantioselective Reductive Heck Hydroarylation of Alkenes
Lucas J Oxtoby1, Zi-Qi Li1, Van T Tran1
1Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA, 92037, USA.
Abstract:
Metal-coordinating directing groups have seen extensive use in the field of transition-metal-catalyzed alkene functionalization; however, their waste-generating installation and removal steps limit the efficiency and practicality of reactions that rely on their use. Inspired by developments in asymmetric organocatalysis, where reactions rely on reversible covalent interactions between an organic substrate and a chiral mediator, we have developed a transient-directing-group approach to reductive Heck hydroarylation of alkenyl benzaldehyde substrates that proceeds under mild conditions. Highly stereoselective migratory insertion is facilitated by in situ formation of an imine from catalytic amounts of a commercially available amino acid additive. Computational studies reveal an unusual mode of enantioinduction by the remote chiral center in the transient directing group.
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