6439-88-9Relevant academic research and scientific papers
Pd/Cu-Catalyzed C-H/C-H Cross Coupling of (Hetero)Arenes with Azoles through Arylsulfonium Intermediates
Lin, Zeng-Hui,Tian, Ze-Yu,Zhang, Cheng-Pan
supporting information, p. 4400 - 4405 (2021/06/27)
A highly efficient method for the selective formal C-H/C-H cross-coupling of azoles and (hetero)arenes was established through arylsulfonium intermediates under transition-metal catalysis, which produced a variety of 2-(hetero)aryl azoles in good to excellent yields. Advantages of the reaction included mildness, a good functional group tolerance, a wide range of substrates, a high regio- and chemoselectivity, one-pot procedures, and the late-stage functionalization of complex molecules without the use of oxidants, offering a promising strategy for the transition-metal-catalyzed C-H arylation of azoles.
Visible Light-Induced Copper-Catalyzed C—H Arylation of Benzoxazoles?
Ma, Xiaodong,Zhang, Guozhu
supporting information, p. 1299 - 1303 (2020/08/05)
A general method for visible light-induced copper-catalyzed arylation of sp2 C—H bonds of azoles has been developed. The method employs aryl halide as the coupling partner, lithium alkoxide as base. A variety of azoles including benzooxazole and benzothiazole can be arylated. Furthermore, electron-poor heterocycles such as thiophene possessing one electron-withdrawing group can also be arylated.
Copper-Catalyzed Intramolecular C-H Amination: A New Entry to Substituted Xanthine Derivatives
Shimizu, Maki,Hayama, Noboru,Kimachi, Tetsutaro,Inamoto, Kiyofumi
, p. 4183 - 4190 (2017/09/12)
Catalytic synthesis of xanthines was achieved in the presence of a copper catalyst. The process involves copper-catalyzed intramolecular C-H amination of benzamidines that possess a uracil moiety and produces variously substituted xanthines generally in good to high yields. This work introduces a new, facile approach to polysubstituted xanthine compounds..
Unprecedented salt-promoted direct arylation of acidic sp2 C[sbnd]H bonds under heterogeneous Ni-MOF-74 catalysis: Synthesis of bioactive azole derivatives
Nguyen, Huong T.T.,Doan, Duc N.A.,Truong, Thanh
, p. 141 - 149 (2016/12/09)
Herein, nickel-based metal-organic framework, Ni-MOF-74, was synthesized by a solvothermal method and its properties was characterized by a host of techniques. Ni-MOF-74 exhibited exceptional catalytic activity toward the direct arylation of azoles via C[sbnd]H activation while other Ni-MOFs, nickel-based heterogeneous systems, and homogeneous counter parts displayed lower activity. Optimal conditions involved the use of Li2CO3 or KCl salts in diglyme solvent in 18 h and no additional ligand is required. This is the first and unprecedented report using KCl salt as promoter for arylation of heterocycles. By avoiding the use of strong bases and oxidants, optimized conditions are compatible with wide range of functional groups and heterocycles. Furthermore, by taking advantage of large aperture size of Ni-MOF-74, we are able to utilize optimized conditions to successfully synthesize several bioactive arylated azole derivatives. Previous studies using heterogeneous catalysts to approach these bioactive compounds are not performed in the literature. Leaching tests indicated that homogeneous catalysis via leached active nickel species is unlikely. Thus, the catalyst was facilely separated from the reaction mixture and reused several times without significant degradation of the catalytic reactivity.
Arylation, Vinylation, and Alkynylation of Electron-Deficient (Hetero)arenes Using Iodonium Salts
Liu, Chuan,Wang, Qiu
supporting information, p. 5118 - 5121 (2016/10/14)
Arylation, vinylation, and alkynylation of electron-deficient arenes and heteroarenes have been achieved by chemoselective C-H zincation followed by copper-catalyzed coupling reactions using iodonium salts. This approach offers a direct and general access to a wide scope of (hetero)biaryls as well as alkenylated and alkynylated heteroarenes under mild conditions. It is particularly useful and valuable for the rapid and modular synthesis of diverse (hetero)aryl compounds, as demonstrated in the synthesis of transient receptor potential vanilloid 1 (TRPV1) antagonists and angiotensin II receptor type 1 (AT1 receptor) antagonists.
Iron catalyzed oxidative assembly of N-heteroaryl and aryl metal reagents using oxygen as an oxidant
Liu, Kun Ming,Liao, Lian Yan,Duan, Xin Fang
supporting information, p. 1124 - 1127 (2015/01/09)
An equivalent amount of N-heteroaryl and aryl Grignard or lithium reagents, after mediation by an equivalent of titanate, was facilely coupled to furnish N-heteroaryl-aryl compounds under the catalysis of FeCl3/TMEDA at ambient temperature using oxygen as an oxidant. Most of the common N-heteroaryls were all good candidates, and thus provided a general, green and pratical protocol for the flexible construction of various N-heteroaryl-aryl structures. This journal is
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
Synthesis and characterization of amino-NHC coinage metal complexes and application for C-H activation of caffeine
Huang, Hsuan-Jui,Lee, Wei-Chih,Yap, Glenn P.A.,Ong, Tiow-Gan
, p. 64 - 73 (2014/05/06)
This paper describes the synthesis and characterization of silver, copper and gold complexes supported by several amino-NHC ligands with different amino side arms. The transmetallation process using silver-NHC complexes can be used to prepare amino-NHC copper and gold complexes easily in high yield. In addition, the catalytic activities of copper complexes are examined for arylation of caffeine via C-H bond activation.
Copper-catalyzed direct thiolation of xanthines and related heterocycles with disulfides
He, Zuying,Luo, Fang,Li, Yinglong,Zhu, Gangguo
, p. 5907 - 5910 (2013/10/21)
A novel copper-catalyzed, base-free direct thiolation of xanthines and related heterocycles is described, featuring the use of inexpensive Cu(OAc) 2·H2O as the catalyst, O2 as a clean and cheap oxidant, and easy-to-handle
Cobalt induced C-H bond activation and C8-arylation of caffeine with aryl bromides
Zheng, Tingting,Sun, Hongjian,Lu, Faguan,Harms, Klaus,Li, Xiaoyan
, p. 139 - 142 (2013/07/25)
The 8-caffeinyl cobalt(I) complex (C8-caffeinyl)Co(PMe3) 4 (1) was obtained by reaction of caffeine with cobalt(I) complex CoMe(PMe3)4 via CH bond activation with the escape of methane. The reaction of 1 with ar
