2017/08/25 by Wei Zhao, Ryan P. Wurz, Jonas C. Peters +1 · 1 citation
Chemistry · #Radical Photochemical Reactions #Catalytic C–H Functionalization Methods #Sulfur-Based Synthesis Techniques
paper · doi:10.1021/jacs.7b07546
openalex publication_date 2017/08/25 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/01
The Curtius rearrangement is a classic, powerful method for converting carboxylic acids into protected amines, but its widespread use is impeded by safety issues (the need to handle azides). We have developed an alternative to the Curtius rearrangement that employs a copper catalyst in combination with blue-LED irradiation to achieve the decarboxylative coupling of aliphatic carboxylic acid derivatives (specifically, readily available N-hydroxyphthalimide esters) to afford protected amines under mild conditions. This C-N bond-forming process is compatible with a wide array of functional groups, including an alcohol, aldehyde, epoxide, indole, nitroalkane, and sulfide. Control reactions and mechanistic studies are consistent with the hypothesis that copper species are engaged in both the photochemistry and the key bond-forming step, which occurs through out-of-cage coupling of an alkyl radical.