Stereoselective Synthesis of Pyrans from Epoxyalkenes: Dual Catalysis with Palladium and Brønsted Acid.

J Org Chem

Department of Chemistry , Emory University, Atlanta , Georgia 30322 , United States.

Published: June 2018

We describe regio- and stereoselective cycloisomerizations of alcohols tethered to epoxyalkenes, to construct alkene-substituted pyrans. These transformations are best catalyzed by Pd(PPh) in the presence of phosphite ligands, and with diphenylphosphinic acid as an essential Brønsted acid cocatalyst for activation of the epoxyalkene.

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http://dx.doi.org/10.1021/acs.joc.8b00026DOI Listing

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