2,3‐Dichloro‐5,6‐Dicyano‐1,4‐Benzoquinone (DDQ)‐Mediated Tandem Oxidative Coupling/Intramolecular Annulation/Dehydro‐Aromatization for the Synthesis of Polysubstituted and Fused Pyridines
作者:Dongping Cheng、Zhiteng Deng、Xianhang Yan、Mingliang Wang、Xiaoliang Xu、Jizhong Yan
DOI:10.1002/adsc.201900956
日期:2019.11.5
A DDQ‐mediated tandem reaction of 1,3‐diarylpropenes and β‐enaminoesters/4‐aminocoumarins is disclosed. It involves oxidative coupling, intramolecular annulation and dehydro‐aromatization reaction, which provides an efficient and mild method for the synthesis of polysubstituted and fused pyridines under metal‐free conditions.
An effective tandem reaction of 4-aminocoumarins and 1,3-diarylpropenes mediated by Cu(OTf)2/TBHP (tert-butyl hydroperoxide)/O2 that provides various benzopyrano[4,3-b]pyridines in moderate to good yields is disclosed. The reaction proceeds through oxidative coupling, intramolecular cyclization, and dehydro-aromatization. This approach has the advantages of high atom-economy, environmental compatibility
2,3-Dichloro-5,6-dicyano-1,4-benzoquinone(DDQ)/Tert-butyl nitrite(TBN)/O2-mediated tandem reaction for the synthesis of 1-aza-anthraquinones and pyridocoumarins
reaction of 2-aminonaphthoquinone/4-aminocoumarins with 1,3-diarylpropenes mediated by 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ)/tert-butyl nitrite (TBN)/O2 is disclosed. It involves oxidativecoupling, intramolecular annulation and dehydro-aromatization reaction, which provides an efficient and mild method for the synthesis of 1-aza-anthraquinones and pyridocoumarins.