Nucleophile Coordination Enabled Regioselectivity in Palladium-Catalyzed Asymmetric Allylic C-H Alkylation.

Angew Chem Int Ed Engl

Hefei National Laboratory for Physical Sciences at the Microscale, Department of Chemistry, University of Science and Technology of China, Hefei, 230026, China.

Published: November 2019

Branched selectivity in asymmetric allylic C-H alkylation is enabled by using 2-acylimidazoles as nucleophiles in the presence of a chiral phosphoramidite-palladium catalyst. A wide range of terminal alkenes, including 1,4-dienes and allylarenes, are nicely tolerated and provide chiral 2-acylimidazoles in moderate to high yields and with high levels of regio-, and enantio-, and E/Z-selectivities. Mechanistic studies using density-functional theory calculations suggest a nucleophile-coordination-enabled inner-sphere attack mode for the enantioselective carbon-carbon bond-forming event.

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http://dx.doi.org/10.1002/anie.201908960DOI Listing

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