Transition‐Metal Free Electrophilic Aminations of PolyfunctionalO‐2,4,6‐Trimethylbenzoyl Hydroxylamines with Zinc and Magnesium Organometallics

Abstract

AbstractWe reported a new electrophilic amination of various primary, secondary and tertiary alkyl, benzylic, allylic zinc and magnesium organometallics withO‐2,4,6‐trimethylbenzoyl hydroxylamines (O‐TBHAs) in 52–99 % yield. These O‐TBHAs displayed an excellent long‐term stability and were readily prepared from various highly functionalized secondary amines via a convenient 3 step procedure. The amination reactions showed remarkable chemoselectivity proceeding without any transition‐metal catalyst and were usually complete after 1–3 h reaction time at 25 °C. Furthermore, this electrophilic amination also provided access to enantioenriched tertiary amines (up to 88 %ee) by using optically enriched secondary alkylmagnesium reagents of the types‐AlkylMgCH2SiMe3.