Tripeptide Organocatalysts for Stereoselective Conjugate Addition Reactions with N‐Heterocyclic Substituents

N-heterocyclic moieties are abundant among pharmaceuticals and agrochemicals, but a challenge for metalorganic organocatalytic transformations. We present tripeptides of the type H-Pro-Pro-Xaa as catalysts stereoselective conjugate addition reactions between substituted aldehydes electrophiles. Alkyl substituents at N-terminal proline, reactive site, were crucial high chemo- stereoselectivity. Different moieties, even both reaction partners, readily tolerated products obtained in yields 61–95% enantioselectivities up to 98% ee.