Mechanochemical Desymmetrization of Unbiased Bis‐ and Tris‐alkynes to Access 3,5‐Isoxazoles‐Alkyne Adducts and Unsymmetrical Bis‐3,5‐isoxazoles**
Rafael A. Hernandez R., Irini Trakakis, Jean‐Louis Do, Louis A. Cuccia, Tomislav Friščić, Pat Forgione
Abstract
Abstract A mechanochemical desymmetrization of symmetrical bis‐ and tris‐alkynes by a controlled 1,3‐dipolar cycloaddition reaction using nitrile oxide dipoles (NOs). This operationally simple protocol allows access to 3,5‐isoxazole‐alkyne adducts from easily prepared or commercially available symmetrical bis‐ and tris‐alkynes in moderate to excellent yields. In addition, we have highlighted the synthetic utility of 3,5‐isoxazole‐alkyne by developing a route to access, for the first time, β‐ketoenamine‐alkyne derivatives, and unsymmetrical bis‐3,5‐isoxazoles.
Topics & Concepts
AlkyneIsoxazoleChemistryNitrileAdductTrisCycloadditionDesymmetrization1,3-Dipolar cycloadditionCombinatorial chemistryMedicinal chemistryOrganic chemistryCatalysisEnantioselective synthesisBiochemistryChemical Synthesis and AnalysisCatalytic C–H Functionalization MethodsClick Chemistry and Applications