Diastereo- and Enantioselective (3 + 2) Cycloaddition of a New Aza-π-Allylpalladium Zwitterionic Intermediate.

J Org Chem

Laboratoire de Synthèse Organique, UMR 7652, CNRS, Ecole Polytechnique, ENSTA Paris, Institut Polytechnique de Paris, 91128 Palaiseau Cedex, France.

Published: July 2023

Cycloaddition of azaoxyallyl cations or other C─(C═O)─N synthon precursors is a well-established route toward lactams and other -heterocycles, but despite the wide synthetic scope of this approach, enantioselective versions remain scarce. We herein report 5-vinyloxazolidine-2,4-diones (VOxD) as a suitable precursor of a new palladium-π-allylpalladium intermediate. In the presence of electrophilic alkenes, (3 + 2) γ-lactam cycloadducts could be formed with a high level of diastereo- and enantioselectivity.

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http://dx.doi.org/10.1021/acs.joc.3c00707DOI Listing

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