Synthesis of α‐Aryl Acrylamides via Lewis‐Base‐Mediated Aryl/Hydrogen Exchange. Issue 40 (29th August 2022)

• Record Type: Journal Article
• Authors: Lemmerer, Miran; Zhang, Haoqi; Fernandes, Anthony J.; Fischer, Tobias; Mießkes, Marianne; Xiao, Yi; Maulide, Nuno
• Is Part Of: Angewandte Chemie international edition. Volume 61:Issue 40(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-08-29
• Subjects: Amides -- Aromatic Substitution -- C−C Coupling -- Organocatalysis -- Rearrangement; Chemistry -- Periodicals; 540
• DOI: 10.1002/anie.202207475
• Languages: English
• ISSNs: 1433-7851

Abstract

Abstract: Herein we report a method for the synthesis of α‐aryl acrylamides leveraging polar S ‐to ‐C aryl migrations induced by a Lewis basic organocatalyst. In contrast to previously reported radical aryl migrations of sulfonyl acrylimides, this polar process enables subsequent elimination, ultimately leading to a formal aryl/hydrogen exchange including SO2 extrusion. This reaction is selective for electron‐deficient aromatic groups, while tolerating a variety of substituents on nitrogen and in the β‐position, and it delivers useful building blocks for further transformations, including cycloaddition and cyclisation reactions. The mechanism was investigated in detail using quantum chemical calculations, which unexpectedly revealed the Lewis base to be involved in several decisive steps. Abstract : A DABCO‐induced polar aryl migration allows for the synthesis of α‐aryl acrylamides from sulfonyl acrylimides. This reaction proceeds through a formal aryl/hydrogen exchange, including SO2 loss. A range of valuable building blocks have been synthesised and the underlying reaction mechanism has been explored using quantum chemical calculations.