doi:10.1039/c7sc00009jengOrue, A.Uria, U.Roca-López, D.Delso, I.Reyes, E.Carrillo, L.Merino, P.Vicario, J. L.Racemic hemiacetals as oxygen-centered pronucleophiles triggering cascade 1, 4-addition/Michael reaction through dynamic kinetic resolution under iminium catalysis. Development and mechanistic insightsART-2017-985692-Hydroxydihydropyran-5-ones behave as excellent polyfunctional reagents able to react with enals through oxa-Michael/Michael process cascade under the combination of iminium and enamine catalysis. These racemic hemiacetalic compounds are used as unconventional O-pronucleophiles in the initial oxa-Michael reaction, also leading to the formation of a single stereoisomer under a dynamic kinetic resolution (DKR) process. Importantly, by using ß-aryl or ß-alkyl substituted a, ß-unsaturated substrates as initial Michael acceptors either kinetically or thermodynamically controlled diastereoisomers were formed with high stereoselection through the careful selection of the reaction conditions. Finally, a complete experimental and computational study confirmed the initially proposed DKR process during the catalytic oxa-Michael/Michael cascade reaction and also explained the kinetic/thermodynamic pathway operating in each case.2017http://zaguan.unizar.es/record/6099210.1039/c7sc00009jhttp://zaguan.unizar.es/record/60992oai:zaguan.unizar.es:60992info:eu-repo/grantAgreement/ES/DGA/E10info:eu-repo/grantAgreement/ES/MICINN/CTQ2013-44367-C2-1-Pinfo:eu-repo/grantAgreement/ES/MINECO/CTQ2014-52107-Pinfo:eu-repo/grantAgreement/ES/MINECO-FEDER/CTQ2016-76155-RCHEMICAL SCIENCE 8, 4 (2017), 2904-2913by-nchttp://creativecommons.org/licenses/by-nc/3.0/es/info:eu-repo/semantics/openAccess