Chemo‐ and Enantioselective Insertion of Furyl Carbene into the N−H Bond of 2‐Pyridones. (29th June 2021)

• Record Type: Journal Article
• Authors: Wang, Kai; Liu, Ziye; Xu, Guangyang; Shao, Ying; Tang, Shengbiao; Chen, Ping; Zhang, Xinhao; Sun, Jiangtao
• Is Part Of: Angewandte Chemie. Volume 133:Number 31(2021)
• Page Start: 17079
• Page End: 17083
• Publication Date: 2021-06-29
• Subjects: Chemistry -- Periodicals; 540
• DOI: 10.1002/ange.202104708
• Languages: English
• ISSNs: 0044-8249

Abstract

Abstract: Asymmetric carbene insertion reactions represent one of the most important protocols to construct carbon–heteroatom bonds. The use of donor–acceptor diazo compounds bearing an ester group is however a prerequisite for achieving high enantioselectivity. Herein, we report a chemo‐ and enantioselective formal N−H insertion of 2‐pyridones that has been accomplished for the first time with enynones as the donor–donor carbene precursors. DFT calculations indicate an unprecedented enantioselective 1, 4‐proton transfer from O to C. The rhodium catalyst provides a chiral pocket in which the steric repulsion and the π–π interaction of the propeller ligand play a critical role in determining the selectivities. Abstract : A chemo‐ and enantioselective formal N−H insertion has been accomplished for the first time by using enynones as the donor–donor carbene precursors. Distinct with the selective O−H insertion of pyridones for diazo compounds, this reaction occurs exclusively on the desired nitrogen atom. DFT calculations indicate an unprecedented enantioselective O‐to‐C 1, 4‐proton transfer.