Photo-induced energy transfer relay of N-heterocyclic carbene catalysis: an asymmetric α-fluorination/isomerization cascade. Issue 6 (21st December 2020)

• Record Type: Journal Article
• Authors: Jiang, Xinhang; Li, En; Chen, Jiean; Huang, Yong
• Is Part Of: Chemical communications. Volume 57:Issue 6(2021)
• Page Start: 729
• Page End: 732
• Publication Date: 2020-12-21
• Subjects: Chemistry -- Periodicals; 540
• DOI: 10.1039/d0cc07264h
• Languages: English
• ISSNs: 1359-7345

Abstract

Abstract : The geometric configuration of olefin products is often driven by thermodynamic control in synthesis. Abstract : The geometric configuration of olefin products is often driven by thermodynamic control in synthesis. Methods enabling switching of cis / trans selectivity are rare. Recently, photosensitized approaches have emerged as a powerful tool for accomplishing this task. In this report, we report an in situ isomerization of an N-heterocyclic carbene (NHC)-bound intermediate by a photo-induced energy transfer process that leads to selective access of chiral allylic fluorides with a cis -olefin geometry. In the absence of a photocatalyst or light, the reaction proceeds smoothly to give ( E )-olefin products, while the ( Z )-isomer can be obtained under photosensitizing conditions. Preliminary mechanistic experiments suggest that an energy transfer process might be operative.