Inorganic-base-mediated hydroamination of alkenyl oximes for the synthesis of cyclic nitrones

A method based on hydroamination mediated by inorganic base was developed for the synthesis of cyclic nitrones from alkenyl oximes. DFT calculations of the reaction pathway suggested that this hydroamination could proceed through an unprecedented nucleophilic amination of the unactivated alkene by the oxime nitrogen atom. The transition state of this reaction is stabilized by an ionic interaction between a metal cation such as K⁺ and the oxime oxygen and negatively charged alkene moiety. Basic ring building: A method for the synthesis of cyclic nitrones by using alkenyl oximes was developed based on hydroamination mediated by an inorganic base. DFT calculations for the reaction pathway suggested that this hydroamination could proceed through nucleophilic amination of the unactivated alkene by the oxime nitrogen atom, with the transition state stabilized by ionic interaction with a metal cation such as K⁺. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.