Herein, we describe a regio- and diastereoselective
metal-free approach for the assembly of densely functionalized 3,6/
5,6-dihydropyridin-2-ones from γ-EWG-substituted crotonic acids
and imines under 1,1′-carbonyldiimidazole (CDI) activation. The
method developed offers the advantages of a wide range of
functionalities in easily accessible substrates, mild reaction
conditions, and generally high yields. The synthetic utility of this
method has been extended to some core and functional group
transformations. Additionally, the reaction mechanism was studied
by DFT calculations.