1448164-32-6Relevant academic research and scientific papers
Palladium-Catalyzed Electrophilic Functionalization of Pyridine Derivatives through Phosphonium Salts
Che, Yuan-Yuan,Deng, Xuezu,Feng, Chao,Lin, Ling-Zhi,Pei, Bingbing,Yue, Yanni
, p. 16414 - 16419 (2020)
Herein, we report a highly efficient and practical method for pyridine-derived heterobiaryl synthesis through palladium-catalyzed electrophilic functionalization of easily available pyridine-derived quaternary phosphonium salts. The nice generality of this reaction was goes beyond arylation, enabling facile incorporation of diverse carbon-based fragments, including alkenyl, alkynyl, and also allyl fragments, onto the pyridine core. Notably, the silver salt additive is revealed to be of vital importance for the success of this transformation and its pivotal role as transmetallation mediator, which guarantees a smooth transfer of pyridyl group to palladium intermediate, is also described.
Pyridine derivative compound and preparation method thereof
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Paragraph 0036-0038, (2020/08/17)
The invention discloses a pyridine derivative compound and a preparation method thereof. The preparation method comprises the steps: in an inert gas atmosphere, sequentially adding heterocyclic quaternary phosphonium salt, iodide, alkali, a silver additive, a palladium catalyst and a phosphorus ligand into a solvent, to obtain a mixture, wherein the molar ratio of the heterocyclic quaternary phosphonium salt to the iodide to the alkali to the silver additive to the palladium catalyst to the phosphorus ligand is (2.5-25):(1-10):(3-30):(1.2-12):(0.5-5):(1-10), and the molar volume ratio of the iodide to the solvent is 0.1 mmol:1 mL; and then, in an inert gas atmosphere, carrying out reaction on the mixture at the temperature of 62-68 DEG C for 11-13 h, and collecting a reaction product, namely the pyridine derivative compound. According to the preparation method, the adopted raw materials are simple and easy to obtain, the substrate range is wide, the cost is low, the reaction conditionsare mild, and the catalyst dosage is extremely small.
Photoarylation of Pyridines Using Aryldiazonium Salts and Visible Light: An EDA Approach
Bartolomeu, Aloisio De A.,Brocksom, Timothy J.,De Oliveira, Kleber T.,No?l, Timothy,Silva, Rodrigo C.
, (2019/08/26)
A metal-free methodology for the photoarylation of pyridines, in water, is described giving 2 and 4-arylated-pyridines in yields up to 96percent. The scope of the aryldiazonium salts is presented showing important results depending on the nature and position of the substituent group in the diazonium salt, that is, electron-donating or electron-withdrawing in the ortho, meta, or para positions. Further heteroaromatics were also successfully photoarylated. Mechanistic studies and comparison between our methodology and similar metal-catalyzed procedures are presented, suggesting the occurrence of a visible-light EDA complex which generates the aryl radical with no need for an additional photocatalyst.
Direct arylation of n-heteroarenes with aryldiazonium salts by photoredox catalysis in water
Xue, Dong,Jia, Zhi-Hui,Zhao, Cong-Jun,Zhang, Yan-Yan,Wang, Chao,Xiao, Jianliang
supporting information, p. 2960 - 2965 (2014/03/21)
A highly effective visible light-promoted "radical-type" coupling of N-heteroarenes with aryldiazonium salts in water has been developed. The reaction proceeds at room temperature with [Ru(bpy)3]Cl 2×6 H2O as a photosensit
