Fluorocyclization of <i>N</i>‐Propargyl Carboxamides by λ<sup>3</sup>‐Iodane Catalysts with Coordinating Substituents
Shunsuke Takahashi, Yuki Umakoshi, Kaii Nakayama, Yohei Okada, Viktor V. Zhdankin, Akira Yoshimura, Akio Saito
Abstract
Abstract Aiming at the enhanced catalytic activity of fluoro‐λ 3 ‐iodane generated from iodoarene precatalyst with Selectfluor and HF⋅pyridine, this study focused on the λ 3 ‐iodanes bearing coordinating substituents. Compared to 4‐iodoanisole as a precatalyst of our previous method, N ‐methyl‐2‐iodobenzamide or 2‐iodobenzamide worked well in the fluorocyclization of N ‐propargyl carboxamides to oxazoles. Control experiments suggest the equilibrium mixture of iodane‐amine complexes and cyclic iodane fluorides would be involved in the present catalysis. magnified image
Topics & Concepts
ChemistryCatalysisSelectfluorPropargylPyridineAmine gas treatingMedicinal chemistryCombinatorial chemistryOrganic chemistryFluorine in Organic ChemistryOxidative Organic Chemistry ReactionsSynthesis and Catalytic Reactions