Sc(OTf)<sub>3</sub>-Catalyzed Dehydrogenative Cyclization for Synthesis of <i>N</i>-Methylacridones
作者:Xi-An Li、Hong-Li Wang、Shang-Dong Yang
DOI:10.1021/ol400371h
日期:2013.4.19
A novel method has been developed for the synthesis of substituted N-methylacridones from 2-(N-methyl-N-phenylamino)benzaldehydes via dehydrogenative cyclization. This transformation involves two primary processes: the aldehyde first coordinates with Sc(OTf)(3) and induces the aromatic electrophilic substitution (SEAr) reaction to form the active intermediate N-methyl-acridin-9-ol, which is then quickly oxidized in situ to afford the acridones. Furthermore, the procedure involved is both environmental friendly and atom efficient; H2O is the only byproduct in this reaction.
Synthesis of 10-Methylacridin-9(10<i>H</i>)-ones through Cu-Catalyzed Intramolecular Oxidative C(sp<sup>2</sup>)-H Amination of 2-(Methylamino)benzophenones
An efficient synthesis of a diverse set of 10-methylacridin-9(10H)-ones from 2-(methylamino)benzophenones has been developed. The reaction proceeds though Cu-catalyzed intramolecular aromatic C–H amination by using O2 as the sole oxidant to provide the desired products in moderate to good yields. In addition, 2-allylamino- and 2-(benzylamino)benzophenones as well as unprotected substrates can also