Direct oxidative C H amination of quinoxalinones under copper-organic framework catalysis

Electrochemical Dehydrogenative Cross‐Coupling of Quinoxalin‐2(1H)‐ones with Amines for the Synthesis of 3‐Aminoquinoxalinones

“…[4] This protocol is highly significant due to the atom-and step-economy character, whereas an excess of strong oxidants, such as KMnO 4 or AgPy 2 MnO 4 , is required. Recently, Cui [5] and Phan [6] independently reported the copper-catalyzed CÀH amination of quinoxalin-2(1H)-ones for the synthesis of 3-aminoquinoxalinones (Scheme 1). Despite the significant progress, only limited examples for the synthesis of 3-aminoquinoxalinones via direct CÀH amination under metal-free conditions have been reported.…”

Formation of C–C and C–Heteroatom Bonds by C–H Activation by Metal Organic Frameworks as Catalysts or Supports

“…73,74 In this context, recently, a Cubased MOF, Cu-CPO-27 (Figure 11) was reported as a solid heterogeneous catalyst promoting the coupling between quinoxalin-2(1H)-one with morpholine to give 3-morpholinoquinoxalin-2(1H)-one with 84% yield using dimethylacetamide (DMA as solvent at 80 °C under aerobic conditions (Scheme 18). 42 Furthermore, the activity of Cu-CPO-27 was compared with that of a series of MOFs under identical experimental c o n d i t i o n s . F o r i n s t a n c e , F e -M O F -2 3 5 a n d Ni 2 (BDC) 2 (DABCO) showed no activity for the direct C− H amination to give 3-morpholinoquinoxalin-2(1H)-one.…”

“…Quinoxalinone derivatives are synthetic intermediate for the preparation of important drug molecules with application in the formulation of pharmaceutical and agricultural products. − The structure of Cu-CPO-27 was reported by series of researchers and corresponds to a honeycomb-like MOF based on the coordination between Cu­(II) ions with 2,5-dihydroxyterephthalic acid. , In this context, recently, a Cu-based MOF, Cu-CPO-27 (Figure ) was reported as a solid heterogeneous catalyst promoting the coupling between quinoxalin-2­(1H)-one with morpholine to give 3-morpholinoquinoxalin-2­(1H)-one with 84% yield using dimethylacetamide (DMA as solvent at 80 °C under aerobic conditions (Scheme ). Furthermore, the activity of Cu-CPO-27 was compared with that of a series of MOFs under identical experimental conditions. For instance, Fe-MOF-235 and Ni 2 (BDC) 2 (DABCO) showed no activity for the direct C–H amination to give 3-morpholinoquinoxalin-2­(1H)-one.…”

“…The structure of Cu-CPO-27 was reported by series of researchers and corresponds to a honeycomb-like MOF based on the coordination between Cu(II) ions with 2,5-dihydroxyterephthalic acid 73,74. In this context, recently, a Cu-based MOF, Cu-CPO-27 (Figure 11) was reported as a solid heterogeneous catalyst promoting the coupling between quinoxalin-2(1H)-one with morpholine to give 3-morpholinoquinoxalin-2(1H)-one with 84 % yield using DMA as solvent at 80 o C under aerobic conditions (Scheme 18) 42. Furthermore, the activity of Cu-CPO-27 was compared with that of a series of MOFs under identical experimental conditions.…”

Metal-Free Visible-Light-Induced C–H/C–H Cross-Dehydrogenative-Coupling of Quinoxalin-2(H)-ones with Simple Ethers

“…Quinoxalin-2­(1H)-ones represent a valuable class of structural features that are extensively utilized in synthetic chemistry, materials, and pharmaceuticals. − Especially, C3-substituted quinoxalin-2-ones have drawn increasingly synthetic attention from chemists because the C3-substituted groups play an important role in various significant biological activities. − The installation of functional groups in C3-position of quinoxalin-2-ones will offer the chance to extend their applications in pharmaceutical chemistry. − Consequently, much efforts have been made to synthesize C3-substituted quinoxalin-2-ones. − Among them, the functionalization of quinoxalin-2­(1H)-ones at C3–H position is regarded as a direct and powerful method to access C3-substituted quinoxalin-2-ones. − Recently, various C3–H functionalization strategies including arylation, − acylation, , phosphonation, , and amination − of quinoxalin-2­(1H)-ones have been reported. In 2018, Guo and co-workers also presented an elegant iron-catalyzed C–H cyanoalkylation approach to construct 3-cyanoalkylated quinoxalin-2­(1H)-ones from quinoxalin-2­(1H)-ones and cyclobutanone oxime esters (Scheme a) .…”