A visible‐light‐promoted strategy for the decarboxylative C‐3 carbamoylation of quinoxalinone scaffolds is developed. This approach initiates through the formation of an EDA complex between oxamic acid and quinoxalinone. Successive SET and decarboxylative carbamoylation construct the C‒C bond. This method utilizes aerial oxygen as the green oxidant and eradicates the process from the use of external photocatalysts and transition metals. Detailed synthetic and photophysical studies enlighten the reaction pathway.
A F reagent-mediated direct C-H carbamoylation of quinoxalin-2(1H)-ones has been developed. Under roomtemperature, a variety of isocyanides are employed to couple well with quinoxalin-2(1H)-ones affording 42 examples including 30 new compounds. This metal-free mild strategy tolerates a wide range of functional groups and shows environmental friendliness and practicality.
Copper-Catalyzed Direct Carbamoylation of Quinoxalin-2(1<i>H</i>
)-ones with Hydrazinecarboxamides Under Mild Conditions
作者:Xianglong Chu、Yujuan Wu、Haigen Lu、Bingchuan Yang、Chen Ma
DOI:10.1002/ejoc.201901858
日期:2020.3.8
An efficient and simple method for the synthesis of 3‐carbamoylated quinoxalin‐2(1H)‐ones base on copper‐catalyzed directcarbamoylation of quinoxalin‐2(1H)‐ones at C3 position has been reported, This process provides a series of 3‐carbamoylquinoxalin‐2(1H)‐one derivatives in moderate to good yields under mild conditions with good functional group tolerance. This work provides a novel and efficient