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Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Palladium-Catalyzed Diastereoselective Imidoylative Arylation/Carbamoylation of Conjugated 1,3-Enynes
Lian-Jie Li1, Dan Li1, Haixia Zhao1
1Key Laboratory of Functional Molecular Solids, College of Chemistry and Materials Science, Anhui Laboratory of Molecule-Based Materials (State Key Laboratory Cultivation Base), Anhui Normal University, Wuhu 241002, China.
Abstract:
A three- and four-component construction of heterocycle-substituted allenes through palladium-catalyzed cyclization reactions of 1,3-enyne-decorated isocyanides has been developed. Owing to the strong ability of the isocyano group to coordinate to metal centers, a sequential isocyanide/alkene insertion and 1,3-palladium migration facilitated the formation of an allenyl-palladium intermediate. When aryl boronic acids were applied as the coupling partner, arylated allenes could be synthesized diastereoselectively. The allenyl-Pd species could also be captured by carbon monoxide to afford allenyl amide derivatives via a 4-MCR. Diverse 3,4-dihydropyrrole- and 3H-indole-containing allenes could be rapidly accessed under mild conditions with broad functional group tolerance.
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