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Updated: Mar 19, 2026
Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Aerobic Radical-Cascade Alkylation/Cyclization of α,β-Unsaturated Amides: an Efficient Approach to Quaternary
Promita Biswas1, Subhasis Paul1, Joyram Guin2
1Department of Organic Chemistry, Indian Association for the Cultivation of Science, 2A & 2B Raja S. C. Mullick Road, Jadavpur, Kolkata-, 700032, India.
Abstract:
An efficient method for the aerobic radical-cascade alkylation/cyclization of α,β-unsaturated amides to afford functionalized oxindoles with a C3 quaternary stereocenter is described. The process is based on the generation of valuable alkyl radicals through sustainable aerobic C-H activation of aldehydes followed by decarbonylation using O2 as the sole oxidant. This method features a broad substrate scope, inexpensive alkyl radical precursors, and convenient reagents. Finally, the method was successfully applied to the synthesis of alkyl analogues of tetrahydrofuranoindoline and (±)-esermethole.
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