Iminoxyl Radical-Promoted Dichotomous Cyclizations: Efficient Oxyoximation and Aminooximation of Alkenes

A novel iminoxyl radical-involved
metal-free approach to vicinal
oxyoximation and aminooximation of unactivated alkenes is developed.
This method utilizes the dichotomous reactivity of the iminoxyl radical
to furnish a general difunctionalization on alkenes using simple tert-butyl nitrite (TBN) as the iminoxyl radical initiator
as well the carbon radical trap. By using this protocol, oxime featured
4,5-dihydroisoxazoles and cyclic nitrones were facilely prepared from
β,γ- and γ,δ-unsaturated ketoximes, respectively.