Pd-Catalyzed Asymmetric Allylic Substitution Cascade of Substituted 4-Hydroxy-2<i>H</i>-pyrones with <i>meso</i>-Allyl Dicarbonates
Yan Zheng, Siqi Dong, Kai Xu, Delong Liu, Wanbin Zhang
Abstract
An efficient Pd-catalyzed asymmetric allylic substitution cascade of 4-hydroxy-2H-pyrones with meso-allyl dicarbonates has been developed for the synthesis of kinetic chiral tetrahydro-1H-pyrano[4,3-b]benzofuran-1-one products in ≤87% yield and ≤99% ee. The protocol was achieved via a temperature-controlled kinetic control process, which has been illustrated by means of the experimental results and control experiments. The reaction could be conducted on a gram scale, and the resulting product allows for several transformations.
Topics & Concepts
Allylic rearrangementChemistryCatalysisYield (engineering)CascadeBenzofuranSubstitution (logic)Substitution reactionMedicinal chemistryCombinatorial chemistryStereochemistryOrganic chemistryProgramming languageChromatographyMaterials scienceMetallurgyComputer scienceAsymmetric Synthesis and CatalysisChemical synthesis and alkaloidsAxial and Atropisomeric Chirality Synthesis