Alkylidene Meldrum's Acids as Platforms for the Vinylogous Synthesis of Dihydropyranones
Stéphane Wittmann, Thomas Martzel, Cong Thanh Pham Truong, Martial Toffano, Sylvain Oudeyer, Régis Guillot, Chloée Bournaud, Vincent Gandon, Jean‐François Brière, Giang Vo‐Thanh
Abstract
Upon Brønsted base organocatalysis, ketone-derived alkylidene Meldrum's acids proved to be competent vinylogous platforms able to undergo a formal (4+2) cycloaddition reaction with dihydro-2,3-furandione, providing an unprecedented route to 3,6-dihydropyran-2-ones as spiro[4.5]decane derivatives with up to 98 % ee thanks to the commercially available Takemoto catalyst. Preliminary investigation showed that this reaction could be extended to other activated ketones, establishing these alkylidene Meldrum's acids as a novel C4-synthon in the vinylogous series.
Topics & Concepts
SynthonChemistryDihydropyranOrganocatalysisCycloadditionCatalysisKetoneDecaneOrganic chemistryMeldrum's acidBrønsted–Lowry acid–base theoryEnantioselective synthesisSynthetic Organic Chemistry MethodsOxidative Organic Chemistry ReactionsAsymmetric Synthesis and Catalysis