84546-74-7Relevant academic research and scientific papers
Alkylation of quinoxalin-2(1H)-ones using phosphonium ylides as alkylating reagents
Liu, Jun-Jia,Peng, Sha,Yang, Luo
supporting information, p. 9705 - 9710 (2021/11/30)
A practical and efficient methodology for the construction of 3-alkylquinoxalinones through base promoted direct alkylation of quinoxalin-2(1H)-ones with phosphonium ylides as alkylating reagents under metal- and oxidant-free conditions was developed. Various 3-alkylquinoxalin-2(1H)-ones were easily obtained in good to excellent yields. Tentative mechanistic studies suggest that this reaction is likely to involve a nucleophilic addition-elimination process.
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 (2021/08/24)
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.
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.
Peroxide-mediated site-specific C-H methylation of imidazo[1,2-: A] pyridines and quinoxalin-2(1 H)-ones under metal-free conditions
Jin, Shengzhou,Yao, Hua,Lin, Sen,You, Xiaoqing,Yang, Yao,Yan, Zhaohua
supporting information, p. 205 - 210 (2020/01/13)
An effective approach to realize the direct methylation of imidazo[1,2-a]pyridines and quinoxalin-2(1H)-ones with peroxides under metal-free conditions is described. In this protocol, peroxides serve as both the radical initiator and methyl source. Methylated imidazopyridines and quinoxalin-2(1H)-ones were smoothly synthesized in moderate to good yields. A free radical reaction mechanism was proposed to describe the methylation process.
Preparation method of 3-methylquinoxaline-2-(1H)-one derivative
-
Paragraph 0101-0106, (2020/05/30)
The invention discloses a preparation method of a 3-methylquinoxaline-2-(1H)-one derivative. The preparation method comprises the following steps: by taking elemental iodine as an oxidizing agent, sodium sulfite as an additive and tert-butyl hydroperoxide (TBHP) as a methyl source, carrying out a direct methylation reaction on carbon No. 3 on a quinoxaline-2-(1H)-one compound in an organic solvent, and after the reaction is completed, carrying out aftertreatment to obtain the 3-methylquinoxaline-2-(1H)-one derivative. The preparation method uses cheap and easily available reaction raw materials and is simple.
Preparation method of 3-methylquinoxaline-2(1H)-one compounds
-
Paragraph 0070-0072, (2019/08/12)
The invention discloses a preparation method of 3-methylquinoxaline-2(1H)-one compounds. The preparation method comprises the step of performing a visible light catalytic reaction on a quinoxaline ketone compound and iodobenzene diacetate under the action
Visible-light induced decarboxylative alkylation of quinoxalin-2(1H)-ones at the C3-position
Xue, Wenxuan,Su, Yingpeng,Wang, Ke-Hu,Zhang, Rong,Feng, Yawei,Cao, Lindan,Huang, Dangfeng,Hu, Yulai
, p. 6654 - 6661 (2019/07/16)
A simple and efficient method for the visible light induced direct carbon alkylation of quinoxalin-2(1H)-ones at the C3 position is described. This protocol employs cheap and readily available phenyliodine(iii) dicarboxylates as the alkylation reagents to conduct decarboxylative radical coupling reaction with quinoxalin-2(1H)-ones. The process exhibits excellent compatibility to functional groups and provides a convenient and selective access to various 3-alkylquinoxalin-2(1H)-ones in good yields.
A Catalyst-Free Minisci-Type Reaction: the C–H Alkylation of Quinoxalinones with Sodium Alkylsulfinates and Phenyliodine(III) Dicarboxylates
Wang, Liping,Zhao, Jiquan,Sun, Yuting,Zhang, Hong-Yu,Zhang, Yuecheng
, p. 6935 - 6944 (2019/11/11)
A direct C–H alkylation of quinoxalinones at the C-3 position with sodium alkylsulfinates and phenyliodine(III) dicarboxylates has been developed under catalyst-free conditions. A series of 3-alkylquinoxalinones were afforded in moderate to excellent yields in this protocol, which offers a practical and efficient access to biologically interesting 3-alkylquinoxalin-2(1H)-one derivatives.
A new facile, efficient synthesis and structure peculiarity of quinoxaline derivatives with two benzimidazole fragments
Mamedov, Vakhid A.,Zhukova, Nataliya A.,Syakaev, Victor V.,Gubaidullin, Aidar T.,Beschastnova, Tat'Yana N.,Adgamova, Dil'Bar I.,Samigullina, Aida I.,Latypov, Shamil K.
supporting information, p. 1403 - 1416 (2013/02/23)
A highly efficient and versatile method for the synthesis of quinoxaline derivatives with two benzimidazole fragments have been developed on the basis of the ring contraction of 3-(benzimidazo-2-yl)quinoxalin-2(1H)-one with 1,2-diaminobenzene and its various types of substituted and condensed derivatives. Owing to the inter- and intramolecular processes, involving self association, proton exchange, conformational, and/or tautomeric exchanges between several forms for most of the bis-benzimidazolylquinoxalines signals of bridged and neighboring carbon atoms and the hydrogen atoms of the neighboring carbon atoms of benzimidazole fragments in the NMR spectra are broadened. The conjugation between the benzimidazole fragments and the quinoxaline core of the molecules is increased from the quinoxaline derivative (10c) to its thiadiazol[f]- (17) and pyrrolo[a]-(19) annulated derivatives, resulting in a greater planarity of the molecule as a whole.
Copper-catalyzed cascade syntheses of 2 H -benzo[ b ][1,4]thiazin-3(4 H)-ones and quinoxalin-2(1 H)-ones through capturing S and N atom respectively from AcSH and TsNH2
Chen, Dingben,Wang, Zhi-Jing,Bao, Weiliang
supporting information; experimental part, p. 5768 - 5771 (2010/10/03)
A copper-catalyzed cascade method has been developed to synthesize the 2H-benzo[b][1,4]thiazin-3(4H)-ones from 2-halo-N-(2-halophenyl)-acetamides 1 and AcSH via the SN2/deacetylation/coupling process, and to synthesize the quinoxalin-2(1H)-ones from 1 and TsNH2 via the S N2/coupling/desulfonation process. The target products were obtained with diversity at three positions on their scaffolds.
