present reaction conditions. In this tandem approach, involvement of transferhydrogenation of the nitro functionality with in situ generated ammonia, imination, nitrile hydration to amide and oxidative cyclization sequences have been established. The process avoids the use of an external hydrogen source, costly catalysts as well as the isolation of amine and amide intermediates.
Efficient Synthesis of Quinazolinones by Transition‐Metal‐Free Direct Aerobic Oxidative Cascade Annulation of Alcohols with<i>o</i>‐Aminoarylnitriles
作者:Qi Wang、Miao Lv、Jianping Liu、Yang Li、Qing Xu、Xu Zhang、Hongen Cao
DOI:10.1002/cssc.201900265
日期:2019.7.5
A mild and atom‐economic method was developed for direct and efficient synthesis of quinazolinones through a transition‐metal‐free aerobic oxidative cascade annulation reaction of widely available o‐aminoarylnitriles and alcohols. Air could be employed as an effective oxidant under mild conditions, generating water as the only byproduct. Possibly owing to the “cesium effect”, the water‐soluble base