Ligand-Free Pd-Catalyzed and Copper-Assisted C–H Arylation of Quinazolin-4-ones with Aryl Iodides under Microwave Heating
摘要:
A microwave-assisted method for the palladium-catalyzed direct arylation of quinazolin-4-one has been developed under copper-assistance. This method is applicable to a wide range of aryl iodides and substituted (2H)-quinazolin-4-ones. This protocol provides a simple and efficient way to synthesize biologically relevant 2-arylquinazolin-4-one backbones.
Synthesis of quinazolin-4(3H)-ones via electrochemical decarboxylative cyclization of α‑keto acids with 2-aminobenzamides
作者:Qing Tian、Jinli Zhang、Liang Xu、Yu Wei
DOI:10.1016/j.mcat.2020.111345
日期:2021.1
Abstract Herein, an environmentally benign electrochemical protocol has been disclosed for the synthesis of quinazolin-4(3H)-one derivatives from readily available α‑keto acids and 2-aminobenzamides. This decarboxylative cyclization process proceeds conveniently in the absence of any homogeneous metal catalysts, bases, or external oxidants. This protocol also features CO2 by-products, mild reaction
摘要 本文公开了一种环境友好的电化学方案,用于从容易获得的 α-酮酸和 2-氨基苯甲酰胺合成 quinazolin-4(3H)-one 衍生物。这种脱羧环化过程在没有任何均相金属催化剂、碱或外部氧化剂的情况下方便地进行。该协议还具有 CO2 副产物、温和的反应条件(室温和空气气氛)和广泛的底物范围,包括一系列 2,3-二取代喹唑啉酮产品。
Cu/Pd-Catalyzed C-2-H Arylation of Quinazolin-4(3<i>H</i>)-ones with (Hetero)aryl Halides
The regiospecific C-2–Harylation of N-3-substituted quinazolin-4(3H)-ones with a wide range of aryl or (hetero)arylhalides under microwave irradiation was studied. A ligand-dependent palladium/copper bicatalytic system was developed and allowed direct cross-coupling with a variety of (hetero)arylhalides. This useful and scalable procedure promotes the construction of C(sp2)–C(sp2) bonds from arenes
N-Substituted 2-iodobenzamides and enaminones undergo cascade transformations to achieve quinazolinones via a copper-catalyzed Ullmann-type coupling, a Michael addition and a retro-Mannich reaction. A unique stereochemical feature of this domino process was that Z-enaminones reacted without external ligands, whereas E-enaminones required the assistance of ligands.
An efficient metal‐free, (NH4)2S2O8 mediated intramolecularoxidativecyclization for the construction of fused polycyclic quinazolinone derivatives under mild conditions was disclosed. This method provides an efficient and facile approach to the synthesis of polycyclic quinazolinone derivatives (> 40 examples), as well as the natural products tryptanthrin, rutaecarpine, and their analogues.
公开了在温和条件下用于构建稠合多环喹唑啉酮衍生物的高效无金属,(NH 4)2 S 2 O 8介导的分子内氧化环化反应。该方法为合成多环喹唑啉酮衍生物(> 40个实例)以及天然产物色胺酮,芸苔芸香碱及其类似物提供了一种高效简便的方法。
Palladium-Catalyzed Oxidative Three-Component Coupling of Anthranilamides with Isocyanides and Arylboronic Acids: Access to 2,3-Disubstituted Quinazolinones
作者:Chun Qian、Kui Liu、Shou-Wei Tao、Fang-Ling Zhang、Yong-Ming Zhu、Shi-Lin Yang
DOI:10.1021/acs.joc.8b01218
日期:2018.8.17
A novel palladium-catalyzedoxidative three-component coupling of easily accessible N-substituted anthranilamides with isocyanides and arylboronicacids is achieved. This protocol offers an alternative approach toward 2,3-disubstituted quinazolinones with a wide substrate scope and good functional group tolerance.