Hypervalent Iodine Reagent Mediated Oxidative Heterocyclization of Aldoximes with Heterocyclic Alkenes
Akira Yoshimura1,2, Khiem C Nguyen3, Gregory T Rohde4
1Department of Chemistry, Southern Methodist University , Dallas, Texas 75275, United States.
Abstract:
An efficient cycloaddition of heterocyclic alkenes with nitrile oxides generated in situ from the corresponding aldoximes using organohypervalent iodine(III) reagent, [hydroxy(tosyloxy)iodo]benzene (Koser's reagent), has been developed. The oxidative cyclization of various aldoximes with 1-propene-1,3-sultone affords the respective isoxazoline-ring-fused heterobicyclic products in moderate to good yields. Furthermore, the reaction of aldoxime with a cyclic phospholene-oxide under similar conditions produces the corresponding heterobicyclic phospholene oxides in moderate yields. The structures of bicyclic phospholene oxide and two sultones were established by single-crystal X-ray crystallography.
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