Peptide Catalyzed Conjugate Additions to β-Nitroacrylates - Steric Bulk Increases the Reaction Rate.

The organocatalytic conjugate addition of aldehydes to β-nitroacrylates provides direct access to β-ester-γ-nitroaldehydes and, thereby, common structural motifs of many bioactive compounds. However, the deactivation of amine-based catalysts by alkylation with the highly electrophilic nitroacrylates hampers this reaction. Here, we show that the peptide H-Mep-dPro-dGlu-NH, which is reluctant to undergo alkylation, catalyzes this reaction at low catalyst loading (0.