Electron Donor–Acceptor Complex-Enabled Autoinductive Conversion of Acylnitromethanes to Acylnitrile Oxides in a Photochemical Machetti–De Sarlo Reaction: Synthesis of 5-Substituted 3-Acylisoxazoles
Piyaporn Arunkirirote, Pornteera Suwalak, Nattawadee Chaisan, Jumreang Tummatorn, Somsak Ruchirawat, Charnsak Thongsornkleeb
Abstract
High Resolution Image Download MS PowerPoint Slide A photochemical Machetti–De Sarlo reaction has been developed for preparing 5-substituted 3-acylisoxazoles from acylnitromethanes and terminal alkynes. This photochemical protocol utilizes an innovative electron donor–acceptor complex, generated in situ from acylnitromethanes, catalytic LiO t Bu, and 1,1,1,3,3,3-hexafluoro-2-propanol, as a photosensitizer to promote rapid conversion with a broad substrate scope in up to 80% efficiency. A sigmoidal autoinductive kinetic profile is revealed, demonstrating the novel and unique dual catalysis in the first photochemical approach of this reaction.