Development of a general, enantioselective organocatalytic Mukaiyama-Michael reaction with α,β-unsaturated aldehydes

LUMO-lowering organocatalysis has been extended to promote the conjugate addition of S-alkyl and 1-pyrrolyl silylketene acetals to α,β-unsaturated aldehydes, yielding both, syn and anti Mukaiyama-Michael products with high levels of enantioselectivity. This strategy allows for the generation of chemically useful 1,5-dicarbonyl systems and again highlights the utility of organocatalysis.