63536-44-7Relevant academic research and scientific papers
Electro-reductive C-H cyanoalkylation of quinoxalin-2(1H)-ones
Ding, Ling,Liu, Yuxiu,Niu, Kaikai,Wang, Qingmin
supporting information, (2022/01/24)
Herein, we report a practical electro-reductive protocol for the direct C–H cyanoalkylation of quinoxalin-2(1H)-ones via iminyl radical-mediated ring opening. These mild reactions proceed under metal-, reductant-, and reagent-free conditions to provide synthetically useful cyanoalkylated quinoxalin-2(1H)-ones.
Photoinitiated Multicomponent Anti-Markovnikov Alkoxylation over Graphene Oxide
He, Haiping,Hu, Jian,Huang, Qing,Li, Fan,Liu, Liangxian,Nie, Liang,Peng, Xiangjun,Yang, Ming,Yao, Zhiyang,Zhou, Linyi
supporting information, (2022/01/20)
The development of graphene oxide–based heterogeneous materials with an economical and environmentally–friendly manner has the potential to facilitate many important organic transformations but proves to have few relevant reported reactions. Herein, we explore the synergistic role of catalytic systems driven by graphene oxide and visible light that form nucleophilic alkoxyl radical intermediates, which enable an anti-Markovnikov addition exclusively to the terminal alkenes, and then the produced benzyl radicals are subsequently added with N–methylquinoxalones. This photoinduced cascade radical difunctionalization of olefins offers a concise and applicable protocol for constructing alkoxyl–substituted N–methylquinoxalones.
Visible Light-Promoted Radical Relay Cyclization/C-C Bond Formation of N-Allylbromodifluoroacetamides with Quinoxalin-2(1 H)-ones
Ye, Zhi-Peng,Liu, Fang,Duan, Xin-Yu,Gao, Jie,Guan, Jian-Ping,Xiao, Jun-An,Xiang, Hao-Yue,Chen, Kai,Yang, Hua
, p. 17173 - 17183 (2021/11/18)
A visible light-promoted radical relay of N-allylbromodifluoroacetamide with quinoxalin-2(1H)-ones was developed in which 5-exo-trig cyclization and C-C bond formation were involved. This protocol was performed under mild conditions to facilely offer a variety of hybrid molecules bearing both quinoxalin-2(1H)-one and 3,3-difluoro-γ-lactam motifs. These prepared novel skeletons would expand the accessible chemical space for structurally complex heterocycles with potential biological activities.
Light-driven selective aerobic oxidation of (iso)quinoliniums and related heterocycles
Zhou, Meimei,Yu, Keyang,Liu, Jianxin,Shi, Weimei,Pan, Yingming,Tang, Haitao,Peng, Xiangjun,Liu, Qian,Wang, Hengshan
, p. 16246 - 16251 (2021/05/19)
Selective C1-H/C4-H carbonylation of N-methylene iminium salts, catalyzed by visible-light photoredox and oxygen in the air, has been reported. A ruthenium complex acts as a chemical switch to conduct two different reaction pathways and to afford two diff
C?H Methylation of Iminoamido Heterocycles with Sulfur Ylides**
Ghosh, Prithwish,Kwon, Na Yeon,Kim, Saegun,Han, Sangil,Lee, Suk Hun,An, Won,Mishra, Neeraj Kumar,Han, Soo Bong,Kim, In Su
supporting information, p. 191 - 196 (2020/10/29)
The direct methylation of N-heterocycles is an important transformation for the advancement of pharmaceuticals, agrochemicals, functional materials, and other chemical entities. Herein, the unprecedented C(sp2)-H methylation of iminoamido heterocycles as nucleoside base analogues is described. Notably, trimethylsulfoxonium salt was employed as a methylating agent under aqueous conditions. A wide substrate scope and excellent level of functional-group tolerance were attained. Moreover, this method can be readily applied to the site-selective methylation of azauracil nucleosides. The feasibility of gram-scale reactions and various transformations of the products highlight the synthetic potential of the developed method. Combined deuterium-labeling experiments aided the elucidation of a plausible reaction mechanism.
Visible-Light-Promoted Switchable Synthesis of C-3-Functionalized Quinoxalin-2(1H)-ones
Aganda, Kim Christopher C.,Hong, Boseok,Lee, Anna
supporting information, p. 1443 - 1448 (2021/01/26)
A visible-light-promoted synthesis of quinoxalin-2(1H)-ones has been developed using 9-mesityl-10-methylacridinium perchlorate as an organo-photocatalyst. The atmosphere-controlled method (Ar/air) enabled the selective synthesis of hydroxyl- and acyl-containing quinoxalin-2(1H)-ones under mild reaction conditions without the use of any metal catalysts or toxic reagents. A fluorescent labelling experiment showed that hydroxyl-containing quinoxalin-2(1H)-ones may have utility in various biological applications as potent fluorophores. (Figure presented.).
Simple and green synthesis of benzimidazoles and pyrrolo[1,2-: A] quinoxalines via Mamedov heterocycle rearrangement
Li, Shichen,Feng, Lei,Ma, Chen
supporting information, p. 9320 - 9323 (2021/06/14)
A method for the synthesis of coupling compounds of benzimidazoles and pyrrolo[1,2-a]quinoxalines via Mamedov Heterocycle Rearrangement is reported here. This method was conducted at room temperature and only solvent (HOAc) was required. A series of 4-(1H-benzo[d]imidazol-2-yl)pyrrolo[1,2-a]quinoxaline derivatives were obtained in moderate to good yields.
Metal-Free Direct Oxidative C?N Bond Coupling of Quinoxalin-2(1H)-ones with Azoles under Mild Conditions
Cai, Yuepiao,Du, Xinyue,Guo, Jingwen,Xia, Qinqin,Zhang, Lina,Zhang, Liting
supporting information, p. 2230 - 2238 (2021/07/22)
Direct C3?H amination of quinoxalin-2(1H)-ones with azoles under mild conditions promoted by PIFA has been achieved in good yield in a very fast manner. Mechanistic study revealed that the reaction proceeds through a radical process. In addition, this method could be applied to gram-scale reaction.
K2S2O8-catalyzed highly regioselective amidoalkylation of diverse N-heteroaromatics in water under visible light irradiation
Chen, Zhi,Li, Jianjun,Ren, Quanlei,Song, Shengjie,Wang, Chaodong,Xu, Ning,Zhou, Jiadi
supporting information, p. 5753 - 5758 (2021/08/23)
A K2S2O8-catalyzed versatile C(sp2)-C(sp3) bond formation with N-heteroaromatics and γ-lactams/amides was developed. Quinoxalin-2(1H)-one, quinoline, isoquinoline, phthalazine, and benzothiazole reacted with γ-lactams/amides to give the corresponding C(sp2)-H amidoalkylation products in moderate to good yields with high regioselectivity. This visible-light-induced photocatalyst-free reaction was conducted in H2O at ambient temperature, which comply with the principles of "green chemistry". The new K2S2O8 catalytic mechanism was investigated with control experiments.
Direct functionalization of quinoxalin-2(1H)-one with alkanes: C(sp2)-H/C(sp3)-H cross coupling in transition metal-free mode
Dagar, Neha,Raha Roy, Sudipta,Singh, Swati
, p. 5383 - 5394 (2021/06/28)
Considering the significance of pharmaceutically important heterocycles, efficient and highly versatile protocols for the functionalization of diverse heterocycles with easily accessible feedstock are crucial. Here, we have reported selective alkylation of quinoxalin-2(1H)-one with a broad class of hydrocarbons having different C(sp3)-H bonds with varying bond strengths using di-tert-butyl peroxide (DTBP) as an alkoxyl radical mediator for hydrogen atom transfer (HAT). This dehydrogenative coupling approach utilizes feedstock chemicals such as cycloalkanes, cyclic ethers and alkyl arenes as coupling partners. This protocol exhibits good functional group compatibility and selectivity regarding both heterocycles and unactivated alkanes. Moreover, this methodology allows functionalization of relatively strong C-H bonds of adamantane and exclusive selectivity towards 3° C(sp3)-H bonds is observed. We also illustrate the applicability of this C(sp2)-H/C(sp3)-H cross-coupling for practical access to bioactive pharmaceuticals.
