Contemporaneous Dual Catalysis: Aldol Products from Non-Carbonyl Substrates.

Chemistry

Department of Chemistry, Stanford University, Stanford, CA 94305 (USA).

Published: October 2015

The aldol reaction represents an important class of atom-economic carbon-carbon bond-forming reactions vital to modern organic synthesis. Despite the attention this reaction has received, issues related to chemo- and regioselectivity as well as reactivity of readily enolizable electrophiles remain. To help overcome these limitations, a new direct approach toward aldol products that does not rely upon carbonyl substrates is described. This approach employs room-temperature contemporaneous lanthanum/vanadium dual catalysis, whereby a vanadium-catalyzed 1,3-transposition of allenols is coupled with a lanthanum-catalyzed Meinwald rearrangement of epoxides in situ to directly form aldol products.

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http://dx.doi.org/10.1002/chem.201502973DOI Listing

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