Hybrid Peptide-Thiourea Catalyst for Asymmetric Michael Additions of Aldehydes to Heterocyclic Nitroalkenes

Bifunctional organocatalysis combining covalent and noncovalent activation is presented. The hybrid peptide-thiourea catalyst features a N-terminal proline moiety for aldehyde activation and a thiourea unit for electrophile activation. This catalyst effectively promotes asymmetric Michael additions of aldehydes to challenging but biologically relevant heterocycle-containing nitroalkenes. The catalyst can be used under solvent-free conditions. Spectroscopic and density functional theory studies elucidate the catalyst structure and mode of action.

Automated summary

A bifunctional organocatalysis combining covalent and noncovalent activation is introduced in this study, using a hybrid peptide-thiourea catalyst for promoting asymmetric Michael additions of aldehydes to challenging nitroalkenes. The catalyst can be utilized under solvent-free conditions, and its structure and mode of action are elucidated through spectroscopic and density functional theory studies.