Palladium-catalyzed addition of alkynes to cyclopropenes: an entry to stereodefined alkynylcyclopropanes.

Org Lett

Aix-Marseille Université, ECM-UMR 6263, ISM2, Av. Escadrille Normandie-Niemen, 13397 Marseille cedex 20, France.

Published: February 2011

The Herrmann-Beller (H-B) phosphapalladacycle catalyzed the addition of terminal alkynes to unsymmetrical gem-disubstituted cyclopropenes to give alkynylcyclopropanes as single diastereomers in good to excellent yields. The stereofacial discrimination at the approach of the bulky alkynylpalladium species is believed responsible for the diastereoselectivity control of the addition reaction.

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http://dx.doi.org/10.1021/ol1028833DOI Listing

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