Asymmetric tandem conjugate addition and reaction with carbocations on acylimidazole Michael acceptors

We present here a stereoselective tandem reaction based on the asymmetric conjugate addition of dialkylzinc reagents to unsaturated acylimidazoles followed by trapping of the intermediate zinc enolate with carbocations. The use of a chiral NHC ligand provides chiral zinc enolates in high enantiomeric purities. These enolates are reacted with highly electrophilic onium compounds to afford densely substituted acylimidazoles. DFT calculations helped to understand the reactivity of the zinc enolates derived from acylimidazoles and allowed their comparison with metal enolates obtained by other conjugate addition reactions.

Beilstein J. Org. Chem. 2023, 19, 881–888. doi:10.3762/bjoc.19.65

Source: Beilstein Journal of Organic Chemistry - June 16, 2023 Category: Chemistry Authors: Beilstein Journal of Organic Chemistry - Syndicated Feeds Tags: acylimidazole asymmetric catalysis carbocation conjugate addition enolate Full Research Paper Source Type: research