4017-20-3Relevant academic research and scientific papers
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).
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 (2019/11/13)
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.).
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.
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
Asymmetric organocatalytic tandem cyclization/transfer hydrogenation: A synthetic strategy for enantioenriched nitrogen heterocycles
Shi, Feng,Tan, Wei,Zhang, Hong-Hao,Li, Mei,Ye, Qin,Ma, Guan-Hua,Tu, Shu-Jiang,Li, Guigen
, p. 3715 - 3726 (2014/01/06)
An asymmetric organocatalytic tandem reaction comprising cyclization/transfer hydrogenation has been established in a compatible and synergistic way, leading to the step-economical synthesis of enantioenriched tetrahydroquinoxalines and dihydroquinoxalinones from readily accessible materials in excellent enantioselectivity of up to >99% ee. This protocol of a one-operation tandem reaction combines the merits of both tandem reactions and asymmetric organocatalysis, providing an efficient strategy for concisely and enantioselectively synthesizing nitrogen heterocycles with biological relevance. Copyright
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.
