Copper-Catalyzed Cyclization and Azidation of γ,δ-Unsaturated Ketone O-Benzoyl Oximes
作者:Hailin Su、Weifei Li、Zhaoli Xuan、Wei Yu
DOI:10.1002/adsc.201400681
日期:2015.1.12
An intramolecular imination/azidation sequence has been realized through the tetrakis(acetonitrile)copper(I) hexafluorophophate [Cu(CH3CN)4PF6]‐catalyzed reaction of γ,δ‐unsaturatedketone O‐benzoyl oximes with trimethylsilyl azide (TMSN3). The reaction proceeds via the copper‐mediated NO cleavage and subsequent CN forming 5‐exo cyclization. The thus formed intermediate is then azidated to afford
cascade manner with an aminative cyclization triggered by N−O bond cleavage of an alkene‐tethered oxime ester. Various arenes, including electron‐rich and electron‐poor arenes, and heteroarenes can be employed in the reaction system. Regioselectivity and radical trapping experiments support the involvement of alkyl radical species, which undergo a homolytic aromatic substitution (HAS) to afford the