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61.
Reactions between 5‐ferrocenylisophthalic dichloride and 1,2‐bis(o‐aminophenoxy)ethane yield 1:1‐ and 2:2‐cyclization products with amide linkages, which are marked as L1 and L2 , respectively. The crystal structure of the 2:2‐macrocycle L2 is determined by X‐ray single crystal structure analysis. Interestingly, L2 affords a folded conformation due to the intermolecular π–π interaction between two isophthaloyl groups, so as to stabilize the marcocylic conformation. The electrochemical anion sensing studies of L1 and L2 show that they have a good ability to recognize H2PO4–, and the 2:2‐cyclization products ( L2 ) with two ferrocene groups, more anion binding sites, and larger cavities, give better electrochemical anion recognition results than L1 . 相似文献
62.
A ferrocene-derived P,N-heterodonor ligand was effectively used in a Cu(OAc)2·H2O-catalysed asymmetric 1,3-dipolar cycloaddition of azomethine ylides with maleate derivatives, affording cycloadducts with high yields (up to 96%), diastereoselectivities (>99 dr), and enantioselectivities (up to 99% ee). 相似文献
63.
Motivated by the potential of electrochemical techniques to analyze hybridization events fast and in a simple and cost‐effective way we present here a detection system allowing a parallel electrochemical DNA analysis. For this purpose different probe DNA strands have been immobilized on one electrode. By the use of two different target DNA sequences, both marked with the redox active methylene blue, we can show that hybridization with the complementary probe sh“NA strands can occur without steric hindrance. Each target has been recognized down to 3nM with a very high specificity of the sensor. In addition, we can detect two different ssDNA targets labeled with different redox active molecules, methylene blue and ferrocene, on one sensor surface simultaneously. 相似文献
64.
Rico Packheiser Tobias Rüffer Petra Ecorchard Prof. Dr. Heinrich Lang 《无机化学与普通化学杂志》2010,636(15):2607-2616
The synthesis of a unique series of heteromultinuclear transition metal compounds is reported. Complexes 1‐I‐3‐Br‐5‐(FcC≡C)‐C6H3 ( 4 ), 1‐Br‐3‐(bpy‐C≡C)‐5‐(FcC≡C)‐C6H3 ( 6 ), 1,3‐(bpy‐C≡C)2‐5‐(FcC≡C)‐C6H3 ( 7 ), 1‐(XC≡C)‐3‐(bpy‐C≡C)‐5‐(FcC≡C)‐C6H3 ( 8 , X = SiMe3; 9 , X = H), 1‐(HC≡C)‐3‐[(CO)3ClRe(bpy‐C≡C)]‐5‐(FcC≡C)‐C6H3 ( 11 ), 1‐[(Ph3P)AuC≡C]‐3‐[(CO)3ClRe(bpy‐C≡C)]‐5‐(FcC≡C)‐C6H3 ( 13 ), 1‐[(Ph3P)AuC≡C]‐3‐(bpy‐C≡C)‐5‐(FcC≡C)‐C6H3 ( 14 ), [1‐[(Ph3PAuC≡C]‐3‐[{[Ti](C≡CSiMe3)2}Cu(bpy‐C≡C)]‐5‐(FcC≡C)‐C6H3]PF6 ( 16 ), and [1,3‐[(tBu2bpy)2Ru(bpy‐C≡C)]2‐5‐(FcC≡C)‐C6H3](PF6)4 ( 18 ) (Fc = (η5‐C5H4)(η5‐C5H5)Fe, bpy = 2,2′‐bipyridiyl‐5‐yl, [Ti] = (η5‐C5H4SiMe3)2Ti) were prepared by using consecutive synthesis methodologies including metathesis, desilylation, dehydrohalogenation, and carbon–carbon cross‐coupling reactions. In these complexes the corresponding metal atoms are connected by carbon‐rich bridging units comprising 1,3‐diethynyl‐, 1,3,5‐triethynylbenzene and bipyridyl units. They were characterized by elemental analysis, IR and NMR spectroscopy, and partly by ESI‐TOF mass spectrometry., The structures of 4 and 11 in the solid state are reported. Both molecules are characterized by the central benzene core bridging the individual transition metal complex fragments. The corresponding acetylide entities are, as typical, found in a linear arrangement with representative M–C, C–CC≡C and C≡C bond lengths. 相似文献
65.
66.
Yuji Suzaki 《Journal of organometallic chemistry》2010,695(23):2512-213
Cyclization reactions of Fe{C5H4OCH2(CH2OCH2)nCH2OTs}2 (n = 1, 2) with C6H4-1,2-(OH)2, C6H4-1,3-(OH)2, and Fe(C5H4OAc)2 under basic conditions yield the corresponding macrocyclic 1,1′-ferrocenophanes. The ferrocenophane having a pyrido-crown ether structure was also synthesized. These ferrocenophanes were characterized by X-ray crystallography and NMR spectroscopy. Cyclic voltammograms of the ferrocenophanes exhibited reversible redox peaks assigned to the oxidation and reduction of the ferrocene unit. The macrocyclic pyrido-containing ferrocenophane forms pseudorotaxane with [NH2{(CH2)9Me}2]BARF (BARF = B{C6H3-3,5-(CF3)2}4) in CDCl3. 相似文献
67.
The rigid [6]ferrocenophane, L1, was synthesised by condensation of 1,1′-ferrocene dicarbaldehyde with trans-1,2-diaminocyclohexane in high dilution at r.t. followed by reduction. When other experimental conditions were employed, the [6,6,6]ferrocenephane (L2) was also obtained. Both compounds were characterised by single crystal X-ray crystallography. The protonation of L1 and its metal complexation were evaluated by the effect on the electron-transfer process of the ferrocene (fc) unit of L1 using cyclic voltammetry (CV) and square wave voltammetry (SWV) in anhydrous CH3CN solution and in 0.1 M nBu4NPF6 as the supporting electrolyte. The electrochemical process of L1 between −300 and 900 mV is complicated by amine oxidation. On the other hand, an anodic shift from the fc/fc+ wave of L1 of 249, 225, 81 and 61 mV was observed by formation of Zn2+, Ni2+, Pd2+ and Cu2+ complexes, respectively. Whereas Mg2+ and Ca2+ only have with L1 weak interactions and they promote the acid-base equilibrium of L1. This reveals that L1 is an interesting molecular redox sensor for detection of Zn2+ and Ni2+, although the kinetics of the Zn2+ complex formation is much faster than that of the Ni2+ one. The X-ray crystal structure of [PdL1Cl2] was determined and showed a square–planar environment with Pd(II) and Fe(II) centres separated by 3.781(1) Å. The experimental anodic shifts were elucidated by DFT calculations on the [ML1Cl2] series and they are related to the nature of the HOMO of these complexes and a four-electron, two-orbital interaction. 相似文献
68.
Roya Akbarzadeh 《Journal of organometallic chemistry》2010,695(21):2320-3424
An efficient and simple synthesis of ferrocenyl bis-amides by the Ugi four-component reaction of ferrocenecarboxaldehyde, carboxylic acids, isocyanides and amines in methanol at room temperature is reported. 相似文献
69.
Gilles Gasser Jonathan D. Carr Stephen J. Green Sean M. Cafferkey James H.R. Tucker 《Journal of organometallic chemistry》2010,695(2):249-3763
Two new ligand derivatives of ferrocene, namely N-4-[3,5-di-(2-pyridyl)-1,2,4-triazoyl]ferrocene carbimine (L1) and N-4-[3,5-di-(2-pyridyl)-1,2,4-triazoyl]ferrocene carbamide (L2), were synthesised in good yields by reacting the known compound 3,5-di-pyridine-2-yl-[1,2,4]triazol-4-ylamine (1) with ferrocenecarbaldehyde and chlorocarbonyl ferrocene, respectively. The structures of L1 and L2 were determined by X-ray crystallography. The complexation of L1 and L2 with CuI, AgI, ZnII and CdII was studied by NMR and UV-vis spectroscopies, as well as by electrochemistry, with titrations used to determine metal:ligand stoichiometries. The cyclic voltammograms of L1 and L2 and their respective complexes indicated reversible one-electron transfers corresponding to the Fc0/+ redox couple (Fc = ferrocene), with formal electrode potentials shifting to more positive values upon metal complexation. 相似文献
70.
Planarly chiral ferrocene derivatives with bridged cyclopentadienyl rings are interesting ligands in asymmetric catalysis. A planar stereogenic unit is conveniently introduced by diastereoselective ortho-lithiation. The directed lithiation of several [5]ferrocenophane derivatives followed by quenching with chlorodiphenylphosphane led to planarly chiral ligands. The sense of diastereoselection was studied by computational methods. Absolute configuration of methoxy phosphane was determined by single crystal X-ray diffraction study. 相似文献