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Updated: Jun 10, 2025

Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Remote Enantioselective ϵ-Alkylation of Copper Ethynylallenylidenes: Precise Control of Central and Axial Chirality
Yu-Hua Wen1, Minghao Liu1, Yu-Hao Wang1
1Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemistry, University of Science and Technology of China, Hefei, 230026, China.
Abstract:
Chiral tetrasubstituted allenes have emerged as important architectures for engineering biologically active compounds. The construction of unique tetrasubstituted allene scaffolds with precise control of continuous central and axial chirality remains yet to be developed. Here, we report a remote enantioselective ϵ-alkylation of yne-propargylic acetates with enals enabled by NHC and copper cooperative catalysis, leading to a series of tetrasubstituted allenes with excellent enantioselectivities (up to >99 % ee) and diastereoselectivities (up to >95 : 5 dr). This method features high regioselectivity and simultaneous control of axial and central chirality. Mechanistic studies suggest a cooperative activation mode and synergistic control of distal chirality created from the copper ethynylallenylidenes.
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