33073-93-7Relevant academic research and scientific papers
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
, p. 5170 - 5175 (2019)
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.).
α-Keto Acids as Triggers and Partners for the Synthesis of Quinazolinones, Quinoxalinones, Benzooxazinones, and Benzothiazoles in Water
Huang, Jian,Chen, Wei,Liang, Jiazhi,Yang, Qin,Fan, Yan,Chen, Mu-Wang,Peng, Yiyuan
, p. 14866 - 14882 (2021/10/25)
A general and efficient method for the synthesis of quinazolinones, quinoxalinones, benzooxazinones, and benzothiazoles from the reactions of α-keto acids with 2-aminobenzamides, benzene-1,2-diamines, 2-aminophenols, and 2-aminobenzenethiols, respectively, is described. The reactions were conducted under catalyst-free conditions, using water as the sole solvent with no additive required, and successfully applied to the synthesis of sildenafil. More importantly, these reactions can be conducted on a mass scale, and the products can be easily purified through filtration and washing with ethanol (or crystallized).
Microwave-Assisted Synthesis of Heterocycles from Aryldiazoacetates**
Cousin, étienne,Elumalai, Vijayaragavan,Hansen, J?rn H.,Hansen, Stephanie R.,Kristoffersen, Tone,Starck, Eliot,Wagner, Lucille J.
, p. 7069 - 7078 (2020/11/30)
Herein, we describe a rapid microwave-assisted, metal-free synthesis of substituted quinoxalinones and quinoxalines using the carbene-mediated reaction between aryldiazo esters and 1,2-diamines. The reaction can encompass a range of substituents and structural variations to afford quinoxalin-2-ones in 14–80 % yield and corresponding quinoxalines in good to excellent yields upon oxidation (67–96 %). The approach can be employed to generate symmetrical and unsymmetrical 2,3-diarylquinoxalines, bis-quinoxalines as well as novel quinoxaline-substituted diazo esters and should be a valuable addition to the heterocycle synthesis toolbox.
A niobium-catalyzed coupling reaction of α-keto acids with: Ortho -phenylenediamines: Synthesis of 3-arylquinoxalin-2(1 H)-ones
Ebersol, Camila,Rocha, Nicole,Penteado, Filipe,Silva, Márcio S.,Hartwig, Daniela,Lenard?o, Eder J.,Jacob, Raquel G.
supporting information, p. 6154 - 6160 (2019/11/20)
A general methodology to access valuable 3-arylquinoxalin-2(1H)-ones was developed, by the reaction of α-keto acids with ortho-phenylenediamines in the presence of ammonium niobium oxalate (ANO) as a catalyst. The reactions were conducted in only 10 min under ultrasonic irradiation as an alternative energy source, affording water as the only co-product. A total of twenty-three different 3-arylquinoxalin-2(1H)-ones were selectively obtained in good to excellent yields by this atom-efficient protocol. Additionally, 1H-15N HMBC experiments were used to reveal the regioisomerism of the obtained products.
Ambient and aerobic carbon-carbon bond cleavage toward α-ketoester synthesis by transition-metal-free photocatalysis
Yu, Qing,Zhang, Yating,Wan, Jie-Ping
supporting information, p. 3436 - 3441 (2019/06/24)
The α-oxoesterification of the CC double bond in readily available enaminones enabling efficient synthesis of α-ketoesters is developed. The reactions showing general tolerance to the reactions of primary and secondary alcohols proceed well under air via Rose Bengal (RB)-based photocatalysis. Particularly, this mild synthetic method has been discovered to tolerate various polyhydroxylated substrates such as phenolic alcohol, diols and triols with an excellent selectivity of mono-oxoesterification. What is more noteworthy is that α-ketoester functionalized 16-dehydropregnenolone acetate resulting from the elaboration on a natural product has been obtained practically.
Visible-light-induced, copper(i)-catalysed C-N coupling between o-phenylenediamine and terminal alkynes: One-pot synthesis of 3-phenyl-2-hydroxy-quinoxalines
Sagadevan, Arunachalam,Ragupathi, Ayyakkannu,Hwang, Kuo Chu
, p. 2110 - 2118 (2013/12/04)
Visible-light-initiated aerobic direct C-N coupling between o-phenylenediamines and terminal acetylenes was performed using simple copper(i) chloride as a catalyst for the synthesis of quinoxaline derivatives. The current method works well for a wide range of electron rich as well as electron poor group-substituted o-phenylenediamines and phenylacetylenes. The key component in the reaction is the direct photo-excitation of in situ generated copper arylacetylide (λabs = 420-480 nm). Moreover, as compared to the literature reports (thermal process), the current photochemical method is simple, mild, high yielding, and more viable towards the construction of biologically important quinoxaline derivatives from easily accessible raw materials, without the need of ligands and strong oxidants.
An efficient synthetic protocol for quinoxalinones, Benzoxazinones, and benzothiazinones from 2-oxo-2-aryl-acetyl bromide precursors
Nagaraj, Muthupandi,Sathiyamoorthy, Sithuraj,Boominathan, Muthusamy,Muthusubramanian, Shanmugam,Bhuvanesh, Nattamai
, p. 1146 - 1151 (2013/10/21)
α-Bromoketones undergo selenium dioxide oxidation to yield reactive 2-oxo-2-arylacetyl bromides that are trapped by aryl-1,2-diamines, 1,2-aminophenol or 1,2-aminothiophenol to give quinoxalinones, benzoxazinones, and benzothiazinones, respectively, in go
The first general, highly enantioselective lewis base organocatalyzed hydrosilylation of benzoxazinones and quinoxalinones
Xue, Zhou-Yang,Jiang, Yan,Peng, Xiao-Zhi,Yuan, Wei-Cheng,Zhang, Xiao-Mei
supporting information; experimental part, p. 2132 - 2136 (2010/11/04)
The first general, highly enantioselective hydrosilylation of benzoxazinones and quinoxalinones has been developed. The chiral Lewis base organocatalysis that are readily accessible from (1S,2R)-ephedrine and (1R,2S)-ephedrine promoted the title reaction to afford various chiral dihydrobenzoxazinones and dihydroquinoxalinones with good yields as well as good enantioselectivities.
Quinoxalin-2-one derivatives, compositions which protect useful plants and comprise these derivatives, and processes for their preparation and their use
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Page/Page column 35, (2008/06/13)
Compounds of the formula (I) and salts thereof in which X is O or S; (Y)n=n substituents Y, n is 0, 1, 2, 3 or 4, R1 is H, OH, NH2, (C1-C4)-alkylamino, di-[(C1-C4)-alkyl]amino or optionally substituted (C1-C10)-alkyl, (C3-C10)-alkenyl, (C3-C10)-alkynyl or (C1-C10)-alkoxy, (C3-C10)-cycloalkyl, (C4-C10)-cycloalkenyl, aryl or heterocyclyl, R2 is H or optionally substituted (C1-C10)-alkyl, (C3-C10)-alkenyl, (C3-C10)-alkynyl, (C3-C10)-cycloalkyl, (C4-C10)-cycloalkenyl, aryl or heterocyclyl, where the radicals Y are as defined in claim 1 are suitable for use as safeners for crop plants or useful plants against the phytotoxic actions of agrochemicals such as pesticides in these plants.
