Enantioselective Cascade Annulation of 1,2,3-Triazoles and Enals Enabled by Sequential Rhodium and Oxidative NHC Catalysis Involving Cleavage, Migration, and Cyclization

Organic Letters, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 28, 2025

The in situ-generated pyrrolin-3-ones serve as novel and versatile synthons, being employed intermediates for the efficient production of pyrrole-fused lactones with high yield excellent enantioselectivity. Herein, we introduce emerging rhodium oxidative N-heterocyclic carbene relay catalysis that enables a highly enantioselective cascade annulation between easily available 1,2,3-triazoles enals. In this proof-of-concept study, engage α,β-unsaturated acylazolium generated from enals via catalysis.

Language: Английский

Regioselective Alkylacylation of 1,3-Dienes by Merging N-Heterocyclic Carbene Catalysis with Photoinduced Palladium Catalysis

Organic Letters, Journal Year: 2024, Volume and Issue: unknown

Published: Dec. 17, 2024

Herein, we develop a dual catalytic platform for the 1,2- or 1,4-alkylacylation reaction of 1,3-dienes with readily available alkyl halides and aldehydes by merging N-heterocyclic carbene catalysis photoinduced palladium catalysis. A series β,γ-unsaturated ketones are obtained in good to high yields. Mechanistic studies suggest that this involves radical process. The direct synthesis flavanone from salicylaldehyde exemplified potential capability platform.

Language: Английский