7209-74-7Relevant academic research and scientific papers
A 2 - aryl flavone preparation method
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Paragraph 0034; 0035; 0036; 0037, (2018/07/15)
The invention discloses a 2 - aryl flavone preparation method, including: in the silver catalyst and under the action of the oxidizing agent, ortho-hydroxy aryl formyl formic acid and aryl alkynoic ring reaction in a solvent, after the reaction is finished after treatment to obtain the 2 - aryl flavone. The method of this invention easily obtained and cheap agents, mild reaction conditions, reaction functional group compatibility is good, cheap catalyst, the catalytic system is simple.
Silver-catalyzed Double Decarboxylative Radical Alkynylation/Annulation of Arylpropiolic Acids with α-keto Acids: Access to Ynones and Flavones under Mild Conditions
Meng, Mengting,Wang, Guofang,Yang, Liangfeng,Cheng, Kai,Qi, Chenze
supporting information, p. 1218 - 1231 (2018/02/16)
Ynones are privileged building blocks in various organic syntheses of heterocyclic derivatives due to their multifunctional nature, and flavones are an important class of natural products with a wide range of biological activities. We describe the catalytic double decarboxylative alkynylation of arylpropiolic acids with α-keto acids. With Ag(I)/persulfate as the catalysis system, the valuable ynones bearing various substituents could be easily obtained. The introduction of hydroxyl substituent on ortho-site of α-keto acids make this strategy further applicable to the construction of flavone derivatives via heteroannulation in moderate to good yields with a similar silver-catalyzed system. The reactions proceed under relatively mild reaction conditions and tolerate a wide variety of functional groups. Control experiments indicated that both the reactions undergo radical processes. (Figure presented.).
One Pot Synthesis of γ-Benzopyranones via Iron-Catalyzed Aerobic Oxidation and Subsequent 4-Dimethylaminopyridine Catalyzed 6-endo Cyclization
Zhai, Di,Chen, Lingzhu,Jia, Minqiang,Ma, Shengming
supporting information, p. 153 - 160 (2017/11/23)
One-pot synthesis of γ-benzopyranones was realized in decent yields and excellent regioselectivities via iron-catalyzed aerobic oxidation and 4-dimethylaminopyridine-catalyzed cyclization of related propargylic alcohols. Derivatizations to aromatic substituted γ-benzopyranones and synthesis of naturally occurring 3′,4′-dimethoxyflavone have also been realized. (Figure presented.).
The five carbonyl iron as CO release source preparation benzopyranone compounds (by machine translation)
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Paragraph 0014; 0043-0046, (2017/07/06)
The invention discloses a five-carbonyl iron as CO release source preparation benzopyranone compound of the method, the method to acetic acid palladium are the catalyst, piperazine is alkali, five carbonyl iron as CO release source, so that the 2 - iodo phenol compound with a terminal alkyne under mild condition coupled reactions, generating benzopyranone compounds. The invention has simple operation, mild reaction conditions, less catalyst levels, low source amount used CO release, toxicity is relatively small, low cost, wide applicability of the substrate, the target substance high yield, natural product can be widely used for the preparation of the benzopyranone compound. (by machine translation)
Pd catalyzed couplings of “superactive esters” and terminal alkynes: Application to flavones and γ-benzopyranones construction
Yang, Dandan,Wang, Zhenhua,Wang, Xiu,Sun, Huaming,Xie, Zunyuan,Fan, Juan,Zhang, Guofang,Zhang, Weiqiang,Gao, Ziwei
, p. 24 - 29 (2016/12/09)
Lewis base, N-methylmorpholine (NMM) accelerated Pd-catalyzed Sonogashira coupling of steric hindered super active esters, 1a–1e, and terminal alkynes. This approach provided an efficient synthetic protocol for a broad array of acylated o-alkynoylphenols compounds, 3a–3e, under moderate conditions. The mechanistic study clearly demonstrated that NNM stabilized the catalytic palladium species, and accelerated the leaving of triazine moiety during the catalytic cycle of the cross-coupling reactions. In addition, piperazine was found to efficiently catalyze the 6-endo cyclization of acylated o-alkynoylphenols, which achieved the diversity oriented synthesis of γ-benzopyranones, 4aa–4eg, with 93–99% yields.
Photochemistry of chromones: Photoreorganisation of 3-alkoxy-2-thienyl-4-oxo-4H-1-benzopyrans
Gupta, Satish C.,Sharma, Somesh,Saini, Ashok,Dhawan, Som N.
, p. 2391 - 2395 (2007/10/03)
Photoirradiation of a methanolic solution of 3-alkoxy-2-thienyl-4-oxo-4H-1-benzopyrans with Pyrex filtered UV light leads to cyclised and cyclodehydrogenated angular products involving both thiophene and alkoxy groups. The reaction is initiated through H-abstraction. The product distribution depends upon the substituents on the thiophene ring.
