14625-58-2Relevant articles and documents
Heteroleptic palladium(II) complexes containing N-heterocyclic carbenes and 4-phenyl-1H-1,2,3-triazole: Synthesis, characterization, and catalytic application
Chen, Wei,Yang, Jin
, p. 1 - 12 (2018)
Reaction of the dimeric N-heterocyclic carbene (NHC) palladium compounds [Pd(μ-Cl)(Cl)(NHC)]2 with 4-phenyl-1H-1,2,3-triazole gave four mono- and dinuclear complexes 1–4. Mononuclear complexes 1 and 2 [(NHC)PdCl2(4-phenyl-1H-1,2,3-triazole)] were obtained when the reactions were performed in CH2Cl2, whereas dinuclear complexes 3 and 4 [Pd2(μ-Cl)(μ-4-phenyl-1H-1,2,3-triazole)Cl2(NHC)2] were obtained when the reactions were performed in THF in reflux with Et3N as the base. Further explorations of the catalytic properties of 1–4 for Pd-catalyzed transformations have been performed and these complexes exhibited moderate to high catalytic activities for Suzuki–Miyaura coupling and arylation of benzoxazoles with aryl bromides.
Magnetic Nanoparticle Decorated N-Heterocyclic Carbene–Nickel Complex with Pendant Ferrocenyl Group for C–H Arylation of Benzoxazole
Naikwade, Altafhusen,Jagadale, Megha,Kale, Dolly,Gajare, Shivanand,Rashinkar, Gajanan
, p. 3178 - 3192 (2018)
Abstract: Magnetic nanoparticle decorated N-heterocyclic carbene–nickel complex with pendant ferrocenyl group has been prepared by multi-step procedure. The formation of complex was confirmed on the basis of analytical techniques such as Fourier transform infrared (FT-IR), Fourier transform Raman (FT-Raman) and X-ray photoelectron spectroscopy (XPS) as well as by X-ray diffraction (XRD), transmission electron microscopy (TEM) and vibrating sample magnetometer (VSM) analysis. The complex proved to be an efficient heterogeneous catalyst for C–H arylation of benzoxazole with aryl boronic acids. The recycling studies revealed that complex could be reused for six times without significant decrease in catalytic activity. Graphical Abstract: [Figure not available: see fulltext.].
Delivering 2-Aryl Benzoxazoles through Metal-Free and Redox-Neutral De-CF3Process
Qiao, Xinxin,Zhao, Yong-De,Rao, Mingru,Bu, Zhan-Wei,Zhang, Guangwu,Xiong, Heng-Ying
, p. 13548 - 13558 (2021/10/01)
An unexpected cleavage of the Csp3-CF3 bond of CF3-hydrobenzoxazoles has been disclosed, affording a range of 2-aryl benzoxazoles under metal-free and redox-neutral conditions. This transformation has demonstrated broad substrate scope and good compatibility of functional groups. 2-Aryl benzothiazole and 2-aryl benzoimidazole could be smoothly assembled in the same manner. On the basis of preliminary mechanistic studies, base initiated and aromatization driven β-carbon elimination was considered to be the key step for the formation of 2. This reaction offers an alternative, facile, and sustainable route to access important 2-aryl benzoxazole motifs.
Stable Pd(0) Complexes with Ferrocene Bisphosphanes Bearing Phosphatrioxaadamantyl Substituents Efficiently Catalyze Selective C-H Arylation of Benzoxazoles by Aryl Chlorides
Horky, Filip,Císa?ová, Ivana,?těpni?ka, Petr
, p. 4848 - 4856 (2021/10/12)
Versatile applications and unique performance of 1,1’-bis(diphenylphosphanyl)ferrocene (dppf) in coordination chemistry and catalysis prompted the search for its analogs. This contribution describes the synthesis of the first donor-unsymmetric dppf congeners bearing bulky and rigid 1,3,5,7-tetramethyl-2,4,6-trioxa-8-phosphaadamantyl (CgP) donor groups, viz. Ph2PfcPCg (1) and Ph2PfcCH2PCg (2; fc=ferrocene-1,1’-diyl). Bis-phosphanes 1 and 2 were converted into air-stable Pd(0) complexes, [Pd(ma)(L^L)] (L^L=1 and 2; ma=maleic anhydride). Together with [Pd(ma)(dppf)], these complexes were applied as catalysts in Pd-catalyzed C?H arylation of benzoxazoles with aryl chlorides in n-butanol as an environmentally benign solvent. Among all catalysts tested in this study, complex [Pd(ma)(2)] performed the best, providing a high-yield and selective synthesis of 2-arylbenzoxazoles from a range of the generally less reactive chloroarenes at low catalyst loading (typically 1 mol.%). Under similar conditions, the structurally related heterocycles (e. g., 1-methylbenzimidazole and benzothiazole) did not react.