摘要通过1,3-二烷基过氢苯并咪唑鎓盐与氧化银(I)的反应以高收率合成了银(I)N-杂环卡宾配合物,并用作合成钯(II)N-杂环卡宾配合物的金属转移试剂。使用元素分析,1 H NMR和13 C NMR光谱对所有配合物进行表征。研究了Pd(II)-NHC配合物在吡咯衍生物直接芳基化中的催化活性。这些Pd(II)-NHC配合物对吡咯衍生物与易得且廉价的芳基氯化物进行直接芳基化反应显示出良好的催化性能。通过使用1mol%的钯络合物,芳基化反应以中等至良好的产率区域选择性地产生C 2或C 5芳基化产物。
nanocomposites (Pd@PPy) with unique combination of high palladium dispersion (nanoparticle size 2.4 nm) and high palladium content (35 wt%) are efficientcatalysts for the selective arylation of substituted pyrroles and imidazoles with either activated or deactivated aryl bromides. The performances of the recoverable supportedpalladiumcatalyst matches the best performances of homogeneous systems based
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
Regioselective C-2 or C-5 Direct Arylation of Pyrroles with Aryl Bromides using a Ligand-Free Palladium Catalyst
作者:Julien Roger、Henri Doucet
DOI:10.1002/adsc.200900196
日期:——
acetyl or ester at the C-2 position of the pyrrole is tolerated. This environmentally attractive procedure has also been found to be tolerant to a very wide variety of functional groups on the arylbromides such as formyl, acetyl, propionyl, ester, nitrile, nitro, fluoro, methoxy, amino or trifluoromethyl.
Palladium-PEPPSI-NHC Complexes Bearing Imidazolidin-2-Ylidene Ligand: Efficient Precatalysts for the Direct C5-Arylation of N-Methylpyrrole-2-Carboxaldehyde
作者:Murat Kaloğlu、Nazan Kaloğlu、İsmail Özdemir
DOI:10.1007/s10562-021-03561-4
日期:2021.11
The Pd-catalyzed direct arylation of pyrroles is an important research field for organic synthesis and catalysis chemistry. However, imidazolidin-2-ylidene based Pd-NHC complexes (NHC=N-heterocycliccarbene) have not yet been employed as catalysts for the direct C5 mono-arylation of C2-substituted N-methylpyrrole derivatives with aryl halides. Therefore, we now report the synthesis and characterization
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。