Cooperative Lewis acid/N-heterocyclic carbene catalysis

Lewis acid activation with N-heterocyclic carbene (NHC) catalysis has presented new opportunities for enantioselective reaction development. Recent findings illustrate that Lewis acids can play an important role in homoenolate annulations by: enhancement of the reactivity, reversal of the diastereo-or regioselectivity, and activation of previously inactive electrophiles. Additionally, the incorporation of a Lewis acid into Bronsted base-catalyzed conjugate addition allowed for an increase in yields.