Synlett 2024; 35(20): 2453-2458
DOI: 10.1055/a-2403-2383
letter
Special Issue to Celebrate the 75th Birthday of Prof. B. C. Ranu

Asymmetric Intermolecular Conjugate Addition of 3-Substituted 2-Benzofuranones to Maleimides via Noncovalent NHC Catalysis

Bhaskar Deb Mondal
,
Sadhan Gorai
,
Joyram Guin
We gratefully acknowledge the generous financial support from the Science and Engineering Research Board, India, (CRG/2020/000800) and thank CSIR and UGC for fellowships to B.D.M. and S.G.


Abstract

An efficient N-heterocyclic carbene (NHC)-catalyzed asymmetric conjugate addition reaction to afford synthetically challenging benzofuranone derivatives having vicinal all-carbon quaternary and tertiary stereocenters is presented. The reaction operates solely through noncovalent interaction between a newly designed NHC and the substrates, providing access to a series of functionalized benzofuranones in good yields and with high ee values. The protocol applies to preparative-scale synthesis. A catalytic cycle involving a noncovalent substrate–NHC interaction is implicated in the process, based on a mechanistic control study.

Supporting Information



Publikationsverlauf

Eingereicht: 22. Juli 2024

Angenommen nach Revision: 26. August 2024

Accepted Manuscript online:
26. August 2024

Artikel online veröffentlicht:
27. September 2024

© 2024. Thieme. All rights reserved

Georg Thieme Verlag KG
Rüdigerstraße 14, 70469 Stuttgart, Germany