An efficient oxidative cycloaddition of enaminones with nitrile oxides generated in situ from respective aldoximes using hypervalent iodine reagents has been developed. Reactions of various aldoximes with enaminones in the presence of [hydroxy(tosyloxy)iodo]benzene involved the regioselective cycloaddition reaction resulting in the formation of the 3,4-disubstituted isoxazoles in moderate to good yields. Structures of several isoxazole products were confirmed by a single X-ray crystallography.
Bibliographical noteFunding Information:
This work was supported by a research grant from the Russian Science Foundation (RSF-16-13-10081-P), the Tomsk Polytechnic University Competitiveness Enhancement Program (VIU-69/2019) and National Science Foundation ((CHE-1759798). A. S. is thankful to JSPS Fund for the Promotion of Joint International Research (Grant No 16KK0199).
- Hypervalent iodine(III) reagents