The direct C(sp2)-H functionalization and coupling of aromatic N-heterocycles with (hetero)aryl bromides by [PdX2(imidazolidin-2-ylidene)(Py)] catalysts
In this study, a series of air- and moisture-stable imidazolidin-2-ylidene-based new palladiumcomplexes with the general formula [PdX2(NHC)(Py)] were synthesized (NHC = N-heterocyclic carbene, Py = pyridine, X = Cl or I). The structures of the palladiumcomplexes were characterized by different techniques such as 1H NMR, 13C NMR, FT-IR spectroscopy and elemental analysis. The more detailed structural
本研究合成了一系列空气和湿气稳定的咪唑啉-2-亚基新型钯配合物,通式为[PdX 2 (NHC)(Py)](NHC = N-杂环卡宾,Py = 吡啶, X = Cl 或 I)。钯配合物的结构通过1 H NMR、13C NMR、FT-IR光谱和元素分析。通过单晶 X 射线衍射研究确定了一种钯配合物的更详细的结构特征。所有钯配合物的催化活性在五元芳族 N-杂环如 3,5-二甲基异恶唑和 1-甲基-1H-吡咯-2-甲醛与(杂)芳基溴化物存在 1 120 °C 时的 mol% 催化剂负载量。以中等至良好的产率获得了所需的产品。
Ligand-Free-Palladium-Catalyzed Direct 4-Arylation of Isoxazoles Using Aryl Bromides
palladium-catalysed C–H bond activation/arylation of 3,5-disubstituted isoxazolesusingaryl or heteroaryl bromides. Good yields were generally obtained by using 0.1–0.5 mol-% of the air-stable PdCl2 complex as the catalyst. A range of functional groups such as acetyl, formyl, ester, fluoro, nitro, trifluoromethyl or nitrile on the arylbromide is tolerated. This reaction is environmentally attractive, as the
The direct C4-arylation of 3,5-dimethylisoxazole with aryl bromides catalyzed by imidazolidin-2-ylidene based palladium-PEPPSI complexes
作者:Murat Kaloğlu、İsmail Özdemir
DOI:10.1016/j.ica.2020.119454
日期:2020.5
Abstract In this study, the synthesis and characterization of four new imidazolinium salts as carbene precursors and their corresponding four new PEPPSI-type (PEPPSI = Pyridine Enhanced Precatalyst Preparation Stabilization and Initiation) palladium complexes were reported. The structures of these new compounds were characterized by spectroscopic and analytical techniques. The catalytic activities
Synthesis of Quinoxaline-Linked Bis(Benzimidazolium) Salts and Their Catalytic Application in Palladium-Catalyzed Direct Arylation of Heteroarenes
作者:Murat Kaloğlu、Mehmet Hanifi Şahan、Serpil Demir Düşünceli、İsmail Özdemir
DOI:10.1007/s10562-021-03787-2
日期:2022.7
synthesized as bis-N-heterocyclic carbene (NHC) precursors. These bis(NHC) precursors were used as multidentate ligands for the construction of bi(hetero)aryls by palladium-catalyzed direct C-H activation process. The in situ prepared palladium complexes by mixtures of the Pd(OAc)2 and the bis(NHC) precursors were used as the catalyst for direct C-H activation of heteroarenes. These catalytic system exhibited
Rhodium-Catalyzed Synthesis of 2-Aroylpyrimidines via Cascade Heteropolyene Rearrangement
作者:Nikolai Yu. Tiuftiakov、Julia O. Strelnikova、Ilya P. Filippov、Adel R. Khaidarov、Alexander F. Khlebnikov、Alexander S. Bunev、Mikhail S. Novikov、Nikolai V. Rostovskii
DOI:10.1021/acs.orglett.1c02706
日期:2021.9.3
one-step synthesis of cytotoxic 2-aroylpyrimidines by the denitrogenative reaction of 1-tosyl-1,2,3-triazoles with isoxazoles under rhodium catalysis has been developed. According to the density functional theory calculations and control experiments, the disclosed reaction proceeds via the rearrangement of an oxadiazatetraene intermediate involving a cascade of intramolecularaza-Diels–Alder and retro-aza-Diels–Alder