Metal‐Free Tandem One‐Pot Construction of 3,3‐Disubsituted 3,4‐Dihydroquinoxalin‐2(1<i>H</i>)‐Ones under Visible‐Light Photoredox Catalysis
Zhen Yao, Zhenli Luo, Yixiao Pan, Xin Zhang, Bohan Li, Lijin Xu, Peng Wang, Qian Shi
Abstract
Abstract Visible‐light photoredox‐catalyzed metal‐free tandem one‐pot synthesis of 3,3‐disubstituted 3,4‐dihydroquinoxalin‐2(1 H )‐ones from easily accessible 1,2‐diaminobenzenes, α‐ketoesters and 4‐alkyl Hantzsch esters has been described. This mild transformation affords the desired products in 47–93% yields for diversely decorated substrates, and can proceed on a gram‐scale. The efficacy of the current catalysis arises from the use of organic 1,2,3,5‐tetrakis(carbazol‐9‐yl)‐4,6‐dicyanobenzene (4CzIPN) as the photocatalyst and CF 3 CO 2 H as the additive. magnified image
Topics & Concepts
ChemistryTandemPhotoredox catalysisCatalysisPhotocatalysisVisible spectrumAlkylCombinatorial chemistryMetalPhotochemistryOrganic chemistryOptoelectronicsPhysicsMaterials scienceComposite materialSynthesis and Biological EvaluationRadical Photochemical ReactionsSulfur-Based Synthesis Techniques