The rapid catalytic construction of relatively complex molecules in a highly selective manner is an attractive goal in organic synthesis.[1] In the area of N-heterocyclic carbene (NHC) catalysis, the unconventional NHC-mediated activation of enal compounds has led to a diverse set of new reactions,[2] such as lactone and lactam formations,[3] cycloaddition reactions,[4] Michael reactions,[5] and self-redox ester formations.[6, 7] This diversity ...