Gold(I)-Catalyzed Enantioselective [2+2+2] Cycloadditions: An Expedient Entry to Enantioenriched Tetrahydropyran Scaffolds

A straightforward and atom-economical enantioselective approach to highly substituted tetrahydropyrans is reported. The process, which consists of an intermolecular gold-catalyzed [2+2+2] cycloaddition between allenamides, alkenes, and aldehydes, is efficiently catalyzed by both phosphoramidite- and chiral N-heterocyclic carbene-gold catalysts, occurs with complete chemoselectivity and regioselectivity, moderate diastereoselectivity, and moderate to very good enantioselectivities.This work was supported by the Spanish MINECO (Grant Nos. SAF2013-41943-R, CTQ2013-48164-C2-1-P, and CTQ2013-48164-C2-2-P), the Consellería de Cultura, Educación e Ordenación Universitaria (Nos. GRC2013-041 and 2015-CP082), and Centro Singular de Investigación de Galicia accreditation 2016-2019 (No. ED431G/09), the European Regional Development Fund (ERDF), the European Research Council (Adv. Grant No. 340055), and the Junta de Andalucía (Grant No. 2012/FQM 1078). We also thank the Orfeo-Cinqa network.Peer Reviewe