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Updated: Nov 15, 2025

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Alkylidene Meldrum's Acids as Platforms for the Vinylogous Synthesis of Dihydropyranones
Stéphane Wittmann1, Thomas Martzel2, Cong Thanh Pham Truong1
1Institut de Chimie Moléculaire et des Matériaux d'Orsay, CNRS UMR 8182, Université Paris Saclay, 91405, Orsay Cedex, France.
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.
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