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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
Enantioselective intramolecular Friedel-Crafts-type alpha-arylation of aldehydes
K C Nicolaou1, Rüdiger Reingruber, David Sarlah
1Department of Chemistry and The Skaggs Institute for Chemical Biology, The Scripps Research Institute,10550 North Torrey Pines Road, La Jolla, California 92037, USA.
Abstract:
Enantioselective organo-SOMO catalysis has, in the last two years, been the subject of considerable development and exploration. A number of new and unique transformations have been reported, such as alpha-allylation, alpha-oxyamination, alpha-enolation, and alpha-vinylation of aldehydes. Herein, we report a modification of this activation mode that involves the intramolecular Friedel-Crafts-type alpha-arylation of aldehydes carrying electron-donating groups on their aromatic nucleus and its application to the total synthesis of demethyl calamenene, a potent cytotoxic agent against human adenocarcinoma A 549.
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