Enantioselective synthesis of spiro-<i>N</i>,<i>O</i>-ketals <i>via</i> iridium and Brønsted acid co-catalyzed asymmetric formal [4+2] cycloaddition
Xiang-Qi Xie, Xingguang Li, Pei Nian Liu
Abstract
An asymmetric formal [4+2] cycloaddition of cyclic enamides with 2-(1-hydroxyallyl)phenol via iridium and Brønsted acid co-catalysis has been achieved to afford chiral N -unsubstituted spiro- N , O -ketals.
Topics & Concepts
Enantioselective synthesisIridiumCycloadditionCatalysisChemistryBrønsted–Lowry acid–base theoryPhenolMedicinal chemistryCombinatorial chemistryOrganic chemistryStereochemistrySynthesis and Catalytic ReactionsAsymmetric Synthesis and CatalysisCyclopropane Reaction Mechanisms