NHC‐Catalyzed Michael Addition to α,β‐Unsaturated Aldehydes by Redox Activation

Abstract

Through oxidative carbene catalysis the reactivity of enals can be reversed at the β position from the typical electrophilic to nucleophilic (homoenolate chemistry) further to electrophilic reactivity by two consecutive umpolung processes. These redox-activated Michael acceptors show higher reactivity at the β position than that for the starting enals. Their reactions with β-dicarbonyl compounds provide dihydropyranones in good to excellent yields under mild conditions. Detailed facts of importance to specialist readers are published as ”Supporting Information”. Such documents are peer-reviewed, but not copy-edited or typeset. They are made available as submitted by the authors. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.