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Updated: Dec 11, 2025

Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
RETRACTED: Asymmetric remote C-H borylation of aliphatic amides and esters with a modular iridium catalyst
Ronald L Reyes1,2, Miyu Sato2, Tomohiro Iwai2
1Institute for Chemical Reaction Design and Discovery (WPI-ICReDD), Hokkaido University, Sapporo 001-0021, Japan.
Abstract:
Site selectivity and stereocontrol remain major challenges in C-H bond functionalization chemistry, especially in linear aliphatic saturated hydrocarbon scaffolds. We report the highly enantioselective and site-selective catalytic borylation of remote C(sp3)-H bonds γ to the carbonyl group in aliphatic secondary and tertiary amides and esters. A chiral C-H activation catalyst was modularly assembled from an iridium center, a chiral monophosphite ligand, an achiral urea-pyridine receptor ligand, and pinacolatoboryl groups. Quantum chemical calculations support an enzyme-like structural cavity formed by the catalyst components, which bind the substrate through multiple noncovalent interactions. Versatile synthetic utility of the enantioenriched γ-borylcarboxylic acid derivatives was demonstrated.
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