Enantioselective Synthesis of Thiazolopyran Derivatives via a Direct Vinylogous Michael–<i>oxa</i>-Michael Sequence
Abhijit Manna, Shweta Rohilla, Vinod K. Singh
Abstract
-Michael sequence between 5-alkenyl thiazolones and isopropylidene oxindoles has been developed. The reaction is catalyzed by a bifunctional squaramide catalyst that allows to access a wide range of densely substituted thiazolopyran derivatives containing a quaternary stereocenter. This protocol is flexible toward different sterically and electronically tuned substrates and is amenable to gram-scale synthesis and several synthetic transformations.
Topics & Concepts
StereocenterSquaramideMichael reactionEnantioselective synthesisChemistryBifunctionalSteric effectsSequence (biology)StereochemistryCatalysisCombinatorial chemistryOrganocatalysisOrganic chemistryBiochemistrySulfur-Based Synthesis TechniquesSynthesis and Catalytic ReactionsSynthetic Organic Chemistry Methods