137690-08-5Relevant academic research and scientific papers
N, N, N', N'-Tetramethylethylenediamine-Enabled Photoredox-Catalyzed C-H Methylation of N-Heteroarenes
Liu, Fang,Ye, Zhi-Peng,Hu, Yuan-Zhuo,Gao, Jie,Zheng, Lan,Chen, Kai,Xiang, Hao-Yue,Chen, Xiao-Qing,Yang, Hua
, p. 11905 - 11914 (2021)
Aiming at the valuable methylation process, readily available and inexpensive N,N,N′,N′-tetramethylethylenediamine (TMEDA) was first identified as a new methyl source in photoredox-catalyzed transformation in this work. By virtue of this simple methylating reagent, a facile and practical protocol for the direct C-H methylation of N-heteroarenes was developed, featuring mild reaction conditions, broad substrate scope, and scalability. Mechanistic studies disclosed that a sequential photoredox, base-assisted proton shift, fragmentation, and tautomerization process was essentially involved.
Electro-oxidative C-H alkylation of quinoxalin-2(1: H)-ones with organoboron compounds
Niu, Kaikai,Hao, Yanke,Song, Lingyun,Liu, Yuxiu,Wang, Qingmin
supporting information, p. 302 - 306 (2021/01/28)
Radical cleavage of C-B bonds to accomplish C-H functionalization is synthetically appealing but practically challenging. We report herein a mild electro-oxidative method for efficient C-H alkylation of quinoxalin-2(1H)-ones by means of radical addition reactions of alkyl boronic acids and esters and alkyl trifluoroborates to afford C-C coupled products. This journal is
Electro-oxidative C-H azolation of quinoxalin-2(1H)-ones
Ding, Ling,Hao, Yanke,Liu, Yuxiu,Niu, Kaikai,Song, Hongjian,Wang, Qingmin,Zhou, Pan
supporting information, p. 3246 - 3249 (2021/05/21)
We have developed a practical, general protocol for direct C-H azolation reactions of quinoxalin-2(1H)-ones by electro-oxidative cross-coupling. These mild reactions proceed under metal-, oxidant-, and reagent-free conditions to provide synthetically useful azolated quinoxalin-2(1H)-ones. Furthermore, the reactions can be carried out with a pencil lead as an electrode and a 3 V battery as a power source, revealing the remarkable flexibility of this protocol.
Electrochemical chlorination and bromination of electron-deficient C[sbnd]H bonds in quinones, coumarins, quinoxalines and 1,3-diketones
Yu, Dan,Ji, Ruixue,Sun, Zhihui,Li, Wenjie,Liu, Zhong-Quan
supporting information, (2021/11/16)
The electrochemistry-promoted chlorination and bromination of electron-deficient C[sbnd]H bonds was developed, using quinones, coumarins, quinoxalines and 1,3-diketones. This protocol features readily available and safe halogen sources (hydrochloric acid and KBr), high site-selectivity and mild reaction conditions. It could provide an efficient access to a series of chlorinated and brominated quinones, coumarins, quinoxalines and 1,3-diketones.
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.
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.
Electrochemically C-H/S-H Oxidative Cross-Coupling between Quinoxalin-2(1 H)-ones and Thiols for the Synthesis of 3-Thioquinoxalinones
Zhou, Jiadi,Li, Zhonghui,Sun, Zexu,Ren, Quanlei,Zhang, Qiwei,Li, Hu,Li, Jianjun
, p. 4365 - 4372 (2020/04/10)
An electrochemical method for the C(sp2)-H thioetherification of quinoxalin-2(1H)-ones with primary, secondary, and tertiary thiols has been reported. Various quinoxalin-2(1H)-ones underwent this thioetherification smoothly under metal- A nd chemical oxidant-free conditions, affording 3-alkylthiol-substituted quinoxalin-2(1H)-ones in moderate to good yields.
Electrochemical decarboxylative C3 alkylation of quinoxalin-2(1: H)-ones with N -hydroxyphthalimide esters
Niu, Kaikai,Song, Lingyun,Hao, Yanke,Liu, Yuxiu,Wang, Qingmin
supporting information, p. 11673 - 11676 (2020/10/20)
We have developed a protocol for electrochemical decarboxylative C3 alkylation of a wide range of quinoxalin-2(1H)-ones under metal- and additive-free conditions. N-Hydroxyphthalimide esters derived from chain, cyclic, primary, secondary, and tertiary carboxylic acids with a broad scope proved to be suitable substrates. This operationally simple protocol performed in an undivided cell under constant-current conditions is suitable for late-stage functionalization of quinoxalin-2(1H)-ones. The reactions can even be carried out with a 3 V battery as a power source, which demonstrates that organic electrosynthesis can be accomplished without the need for specialized equipment.
Construction of C(sp2)?C(sp3) Bond between Quinoxalin-2(1H)-ones and N-Hydroxyphthalimide Esters via Photocatalytic Decarboxylative Coupling
Yan, Zhiyang,Sun, Bin,Zhang, Xun,Zhuang, Xiaohui,Yang, Jin,Su, Weike,Jin, Can
, p. 3344 - 3349 (2019/09/06)
A novel visible-light-driven decarboxylative coupling of alkyl N-hydroxyphthalimide esters (NHP esters) with quinoxalin-2(1H)-ones has been developed. This C(sp2)?C(sp3) bond-forming transformation exhibits excellent substrate generality with respect to both the coupling partners. Of note, a series of 3-primary alkyl-substituted quinoxalin-2(1H)-ones that were difficult to synthesize by previous methods could be obtained in moderate to excellent yields. Additionally, the mild conditions, easy availability of substrates, wide functional group tolerance and operational simplicity make this protocol practical in the synthesis of 3-alkylated quinoxalin-2(1H)-ones.
Electrochemical Cross-Coupling of C(sp2)?H with Aryldiazonium Salts via a Paired Electrolysis: an Alternative to Visible Light Photoredox-Based Approach
Jiang, Yang-ye,Dou, Gui-yuan,Zhang, Luo-sha,Xu, Kun,Little, R. Daniel,Zeng, Cheng-chu
supporting information, p. 5170 - 5175 (2019/11/13)
Photoredox-based C?H bond functionalization constitutes one of the most powerful and atom-economical approaches to organic syntheses. During this type of reaction, single electron transfer takes place between the photocatalyst (PC) and redox- active substrates. Electrosynthesis also involves electron transfer between substrates and electrodes. In this paper, we focus upon electrochemical cross-coupling of C(sp2)?H with aryldiazonium salts and have developed an efficient electrochemical approach to the Minisci-type arylation reaction. The constant current paired electrosynthesis proceeds in a simple undivided cell without external supporting electrolyte, features a wide range of substrates and is easy to scale-up. These results demonstrate that photoredox-based cross-coupling of C(sp2)?H with aryldiazonium salts can also proceed successfully under paired electrolysis conditions, thereby contributing to understanding of the parallels between photosynthesis and electrosynthesis. (Figure presented.).
