Copper-Catalyzed Synthesis of Azaspirocyclohexadienones from α-Azido-<i>N</i>-arylamides under an Oxygen Atmosphere
作者:Shunsuke Chiba、Line Zhang、Jian-Yuan Lee
DOI:10.1021/ja1027327
日期:2010.6.2
copper-catalyzed reaction of alpha-azido-N-arylamides was found to proceed under an oxygen atmosphere to afford azaspirocyclohexadienones. The present transformation is carried out by a sequence of denitrogenative formation of iminyl copper species from alpha-azido-N-arylamides and their imino-cupration with an intramolecular benzene ring on the amido nitrogen followed by consecutive formation of C=O bonds. The
Friedel–Crafts-type cyclization. The reaction was catalyzed by a trimethylsilyl tricyanopalladate complex generated in situ from trimethylsilyl cyanide and Pd(OAc)2. Wide varieties of diethyl phosphates derivedfrom N-arylmandelamides were converted almost quantitatively into oxindoles. When N,N-dibenzylamide was used instead of an anilide substrate, a benzo-fused δ-lactam was obtained. An oxindole product was subjected