- Oligomerization of phenylferrocenylacetylene under the action of WCl 6
-
Phenylferrocenylacetylene was found to be capable of oligomerizing in the presence of WCl6 (130 °C, 24 h) to afford short polyenes (with about 5 monomer units in the macromolecule) in up to ~30% yield. The polyenes synthesized are promising rea
- Tatarinova, Inna V.,Tarasova, Ol'Ga A.,Markova, Marina V.,Morozova, Lyudmila V.,Mikhaleva, Al'Bina I.,Trofimov, Boris A.
-
-
Read Online
- The syntheses and electrochemical studies of a ferrocene substituted diiminopyridine ligand and its P, S, Se, and Te complexes
-
A new reversible, redox active diiminopyridine ligand (1Fc) containing pendant ferrocene functionalities was isolated and fully characterized. The reaction of 1Fc with chalcogen pseudohalides of sulfur, selenium, and tellurium yielded the respective N,N′,N″-chelated chalcogen dications. Phosphorus chemistry proceeded in a related manner but, in this case, by the direct addition of 1Fc with PI3 to yield the N,N′,N″- chelated P(I) cation. These species represent the first synthesized main group complexes involving a redox active diiminopyridine ligand containing pendant ferrocenes. Electrochemical studies of the free ligand shows a reversible two-electron process. The chelated phosphorus cation, however, displayed three events, the first being a quasi-reversible two-electron process, involving the oxidation at the P(I) center, resulting in a P(III) cation. The subsequent reversible one- and two-electron processes arise from the ligand framework and pendant ferrocenes, respectively.
- Magdzinski, Eleanor,Gobbo, Pierangelo,Martin, Caleb D.,Workentin, Mark S.,Ragogna, Paul J.
-
-
Read Online
- Facile purification of iodoferrocene
-
We report a simple method for purifying large amounts of iodoferrocene, synthesized in one step from ferrocene. Halogenated ferrocene derivatives have been known for some time, but are commonly not purified, as obtaining pure samples typically requires multiple steps and often involves use of highly toxic organomercury complexes. The purification described here takes advantage of the increased oxidation potential of iodoferrocene, relative to ferrocene.
- Goeltz, John C.,Kubiak, Clifford P.
-
-
Read Online
- Synthesis of ferrocene amides and esters from aminoferrocene and 2-substituted ferrocenecarboxylic acid and properties thereof
-
Different ferrocenecarboxamides were synthesized from aminoferrocene and various acid coupling partners such as Nα-Boc-l-tryptophan and N-protected sugar amino acids (N-Boc-3-amino-3-deoxy-1,2-O-isopropylidene-α-d-ribofuranoic acid, N-Boc-3-amino-3-deoxy-1,2-O-isopropylidene-α-d-xylofuranoic acid and their corresponding homo- and hetero-dimers). Similarly, reactions between 2-aminoethyl ferrocenecarboxylate and N-protected sugar amino acids afforded compounds with a carboxamide functional group remotely positioned from the ferrocene core. The X-ray diffraction structure of one of them showed the presence of an intermolecular hydrogen bond between the amide functional groups. Carbonylamino (or carbonyloxy) and oxycarbonyl 1,2-disubstituted ferrocenes were prepared either as racemic mixtures or in enantiomerically pure (SP) form. Their electrochemical evaluation revealed distinctive features. Interestingly, the enantiomerically pure ferrocene diester showed a large potential shift (+45 mV) in the presence of l-glutamic acid. Finally, some of the synthesized ferrocenes were evaluated for their antibacterial, antifungal and antiproliferative (MCF-7) activities.
- Srinivas, Palabindela,Prabhakar, Sunchu,Chevallier, Floris,Nassar, Ekhlass,Erb, William,Dorcet, Vincent,Jouikov, Viatcheslav,Radha Krishna, Palakodety,Mongin, Florence
-
-
Read Online
- Enantioselective Twofold C?H Annulation of Formamides and Alkynes without Built-in Chelating Groups
-
Twofold C?H annulation of readily available formamides and alkynes without built-in chelating groups was achieved. Ni?Al bimetallic catalysis enabled by a bulky BINOL-derived chiral secondary phosphine oxide (SPO) ligand proved to be critical for high reactivity and high selectivity. This reaction uses readily available formamides as starting materials and provides a concise synthetic pathway to a broad range of chiral ferrocenes in 40–98 % yield and 93–99 % ee.
- Chen, Hao,Luan, Yu-Xin,Wang, Yin-Xia,Ye, Mengchun
-
-
Read Online
- Oxidative purification of halogenated ferrocenes
-
We report the large scale syntheses and 'oxidative purification' of fcI2, fcBr2 and FcBr (fc = ferrocene-1,1′-diyl, Fc = ferrocenyl). These valuable starting materials are typically laborious to separate via conventional techniques, but can be readily isolated by taking advantage of their increased E1/2 relative to FcH/FcX contaminants. Our work extends this methodology towards a generic tool for the separation of redox active mixtures.
- Inkpen, Michael S.,Du, Shuoren,Driver, Mark,Albrecht, Tim,Long, Nicholas J.
-
-
Read Online
- Urea-bridged diferrocene: Structural, electrochemical, and spectroelectrochemical studies
-
Urea-bridged diferrocene derivatives N,N′-diferrocenylurea (1) and N,N′-dimethyl-N,N′-diferrocenylurea (2) were prepared and characterized. Single-crystal X-ray analysis shows that Compound 1 has a trans-trans linear conformation whereas Compound 2 has a trans-cis conformation. Both compounds display two consecutive redox couples with, respectively, E1/2 of +0.29 and +0.42 V vs. Ag/AgCl for 1 and +0.31 and +0.50 V for 2. Spectroelectrochemical studies show the presence of distinct intervalence charge transfer (IVCT) transitions for the one-electron-oxidized mixed-valent Compound 1 +, with an estimated electronic coupling parameter of 190 cm-1. By contrast, the one-electron-oxidized Compound 2 + shows much weaker IVCT transitions.
- Gong, Zhong-Liang,Zhong, Yu-Wu
-
-
Read Online
- Bis-ferrocenyl-pyridinediimine trinuclear mixed-valent complexes with metal-binding dependent electronic coupling: Synthesis, structures, and redox-spectroscopic characterization
-
A family of metal dichloride complexes having a bisferrocenyl- substituted pyridinediimine ligand was systematically synthesized ((Fc2PDI)MCl2, M = Mg, Zn, Fe, and Co) and characterized crystallographically, spectroscopically, electrochemically, and computationally. Electronic coupling between the ligand ferrocene units is switched on upon binding to a MCl2 fragment, as evidenced by both sequential oxidation of the ferrocenes in cyclic voltammetry (ΔEox ≈ 200 mV) and by Inter-Valence Charge Transfer electronic excitations in the near IR. Additionally, UV-vis spectra are used to directly observe orbital mixing between the ferrocenyl units and the imine π system since breaking of the orbital symmetry results in allowed transitions (? = 2800 M-1cm-1 vs ? ≈ 200 M-1cm-1 in free ferrocene) as well as broadening and red-shifting of the ferrocenyl transitions-indicating organic character in formerly pure metal-centered transitions. DFT analysis reveals that interaction between the ferrocenes and the MCl2 fragment is small and suggests that communication is mediated by better energy matching between the ferrocene and organic π? orbitals upon coordination, allowing superexchange coupling through the LUMO. Furthermore, single crystal diffraction data obtained from oxidation of one and both ferrocenes show distortions, introducing the empty dxy/dx2-y2 orbitals into the secondary coordination sphere of the MCl2 fragment. Such structural rearrangements are infrequent in ferrocenyl mixedvalent compounds, and implications for catalysis as well as electronic communication are discussed.
- Carter, Cole,Kratish, Yosi,Jurca, Titel,Gao, Yanshan,Marks, Tobin J.
-
-
Read Online
- An environmentally benign and cost-effective synthesis of aminoferrocene and aminoruthenocene
-
An improved synthesis of aminoferrocene has been carried out that adheres with the basic green chemistry guidelines. Amination from aqueous NH3 as the nitrogen source, with the inexpensive CuI/Fe2O3 couple as cocatalyst in ethanolic solution, makes the process environmentally attractive as well as a viable alternative for all practical purposes. This procedure has also been applied to prepare aminoruthenocene, being reported for the first time.
- Leonidova, Anna,Joshi, Tanmaya,Nipkow, David,Frei, Angelo,Penner, Johanna-Elena,Konatschnig, Sandro,Patra, Malay,Gasser, Gilles
-
-
Read Online
- Syntheses and purification of the versatile synthons iodoferrocene and 1,1′-diiodoferrocene
-
This paper describes the improved synthesis and purification of iodoferrocene (FcI) and 1,1′-diiodoferrocene (FcI2). FcI and FcI2 were prepared by mono- and dilithiation of ferrocene followed by conversion into iodoferrocenes by reaction with iodine. Purification was accomplished by a simple sublimation/distillation procedure, affording FcI and FcI2 in high yields (74 and 72%) and high purity (>99.9%). We determined the molecular structures of FcI and FcI2 by X-ray single crystal diffraction. This journal is the Partner Organisations 2014.
- Roemer, Max,Nijhuis, Christian A.
-
-
Read Online
- A new phthalocyanine-ferrocene conjugated dyad
-
The synthesis and optical properties of a new phthalocyanine-ferrocene conjugated dyad are reported. Using a Pd(0)-catalysed cross-coupling reaction, an unsymmetrical substituted metallophthalocyanine linked to a ferrocene subunit by an arylene-alkynylene spacer has been prepared. The electronic properties of this linearly π-conjugated compound and related ones were investigated by UV-visible spectroscopy.
- González-Cabello, Ana,Vázquez, Purificación,Torres, Tomás
-
-
Read Online
- Scalable Synthesis of Functionalized Ferrocenyl Azides and Amines Enabled by Flow Chemistry
-
A scalable access to functionalized ferrocenyl azides has been realized in flow. By halogen-lithium exchange of ferrocenyl halides and trapping with tosyl azide, a variety of functionalized ferrocenyl azides were obtained in high yields. To allow a scalable preparation of these potentially explosive compounds, a flow protocol was developed accelerating the reaction time to minutes and circumventing accumulation of potentially hazardous intermediates. The corresponding ferrocenyl amines were then prepared by a reliable reduction process.
- Boeser, Lisa,Christmann, Mathias,Hartmayer, Bence,Heretsch, Philipp,Kleoff, Merlin,Sarkar, Biprajit,Schwan, Johannes
-
-
Read Online
- Amino ferrocene derivative and organic light emitting diode
-
The invention provides an amino ferrocene derivative. The amino ferrocene derivative is described as in a formula (I) in the specification. In the formula (I), Ar1 and Ar2 are identically or differently selected from substituted or non-substituted aryl groups of C6 to C10. The amino ferrocene derivative provided by the invention can be used as a p-type carrier generation layer in OLED; meanwhile, the OLED connected in series (series type OLED) can obtain the characteristics of high illumination brightness, external quantum efficiency, current efficiency, etc.
- -
-
Paragraph 0035; 0037
(2017/07/01)
-
- Ratiometric electrochemical detection of hydrogen peroxide and glucose
-
Hydrogen peroxide (H2O2) detection is of high importance as it is a versatile (bio)marker whose detection can indicate the presence of explosives, enzyme activity and cell signalling pathways. Herein, we demonstrate the rapid and accurate ratiometric electrochemical detection of H2O2 using disposable screen-printed electrodes through a reaction-based indicator assay. Ferrocene derivatives equipped with self-immolative linkers and boronic acid ester moieties were synthesised and tested, and, through a thorough assay optimisation, the optimum probe showed good stability, sensitivity and selectivity towards H2O2. The optimised conditions were then applied to the indirect detection of glucose via an enzymatic assay, capable of distinguishing 10 μM from the background within minutes.
- Goggins, Sean,Apsey, Ellen A.,Mahon, Mary F.,Frost, Christopher G.
-
supporting information
p. 2459 - 2466
(2017/03/20)
-
- Preparation of Bodipy-ferrocene dyads and modulation of the singlet/triplet excited state of bodipy: Via electron transfer and triplet energy transfer
-
Modulation of the singlet/triplet excited state of a fluorophore is becoming more important for molecular switches, molecular memory devices, chemical or biological sensors and controllable photodynamic therapy (PDT) etc. Boron-dipyrromethene (Bodipy)-ferrocene (Fc) dyads were prepared for reversible electrochemical switching of the singlet excited state (fluorescence), as well as the triplet excited states of Bodipy. The photophysical properties of the dyads were studied using steady-state UV-vis absorption spectroscopy, fluorescence, electrochemical characterization, time-resolved fluorescence and nanosecond transient absorption spectroscopies. The fluorescence of the Bodipy moieties in the dyads was quenched significantly, due to the photo-induced electron transfer (PET). This conclusion was supported by electrochemical characterization and calculation of the Gibbs free energy changes of PET. We demonstrated that the fluorescence of the Bodipy moiety can be reversibly switched ON and OFF by electrochemical oxidation of the Fc moiety (Fc/Fc+). Furthermore, we proved that the Fc moiety is efficient for quenching of the triplet excited states of Bodipy. Two quenching mechanisms, PET and triplet-triplet-energy transfer (TTET), are responsible for the intramolecular and intermolecular quenching of the triplet excited states of the diiodoBodipy unit.
- Wu, Xueyan,Wu, Wenting,Cui, Xiaoneng,Zhao, Jianzhang,Wu, Mingbo
-
supporting information
p. 2843 - 2853
(2016/04/26)
-
- Aminoferrocene derivative and tandem organic light-emitting diode containing the same
-
An aminoferrocene derivative is represented by the formula (I): wherein Ar1 and Ar2 independently represent a substituted or unsubstituted C6-C10 aryl group. The aminoferrocene derivative is useful for forming a p-type carrier generation layer of a tandem OLED so that the tandem OLED has superior luminous efficiencies in terms of maximum luminance, maximum external quantum efficiency, maximum current efficiency, etc.
- -
-
Page/Page column 4; 5
(2016/06/28)
-
- The Crystal Structure of the THF Adduct of Monolithioferrocene
-
Single crystals of [Fe(η5-C5H4)(η5-C5H5)]2Li2(thf)4 (1) were obtained from a tetrahydrofuran solution containing monolithioferrocene. The title compound crystallizes in the monoclinic space group P21 with a = 9.6589(5) ?, b = 17.4285(9) ?, c = 30.3116(15) ?, β = 91.911(2)° and V = 5099.8(5) ?3 with three independent molecules of 1. All individual molecules feature a non- symmetric almost planar Li2C2 four-membered ring with two shorter (2.118-2.215 ?) and two longer Li-C distances (2.257-2.309 ?). The lithium cations are each coordinated by two carbanionic atoms of two ferrocenyl substituents and two tetrahydrofuran molecules in a distorted tetrahedral fashion. All ferrocenyl moieties display an eclipsed conformation of the C5 rings.
- F?rster, Christoph,Heinze, Katja
-
p. 517 - 520
(2015/03/30)
-
- Halide-Mediated Ortho-Deprotonation Reactions Applied to the Synthesis of 1,2- and 1,3-Disubstituted Ferrocene Derivatives
-
The ortho-deprotonation of halide-substituted ferrocenes by treatment with lithium tetramethylpiperidide (LiTMP) has been investigated. Iodo-, bromo-, and chloro-substituted ferrocenes were easily deprotonated adjacent to the halide substituents. The synthetic applicability of this reaction was, however, limited by the fact that, depending on the temperature and the degree of halide substitution, scrambling of both iodo and bromo substituents at the ferrocene core took place. Iodoferrocenes could not be transformed selectively into ortho-substituted iodoferrocenes since, in the presence of LiTMP, the iodo substituents scrambled efficiently even at -78°C, and this process had occurred before electrophiles had been added. Bromoferrocene and certain monobromo-substituted derivatives, however, could be efficiently ortho-deprotonated at low temperature and reacted with a number of electrophiles to afford 1,2- and 1,2,3-substituted ferrocene derivatives. For example, 2-bromo-1-iodoferrocene was synthesized by ortho-deprotonation of bromoferrocene and reaction with the electrophiles diiodoethane and diiodotetrafluoroethane, respectively. In this and related cases the iodide scrambling process and further product deprotonation due to the excess LiTMP could be suppressed efficiently by running the reaction at low temperature and in inverse mode. In contrast to the low-temperature process, at room temperature bromo substituents in bromoferrocenes scrambled in the presence of LiTMP. Chloro- and 1,2-dichloroferrocene could be ortho-deprotonated selectively, but in neither case was scrambling of a chloro substituent observed. As a further application of this ortho-deprotonation reaction, a route for the synthesis of 1,3-disubstituted ferrocenes was developed. 1,3-Diiodoferrocene was accessible from bromoferrocene in four steps. On a multigram scale an overall yield of 41% was achieved. 1,3-Diiodoferrocene was further transformed into symmetrically 1,3-disubstituted ferrocenes (1,3-R2Fc; R = CHO, COOEt, CN, CH = CH2). (Figure Presented).
- Zirakzadeh, Afrooz,Herlein, Alexander,Gross, Manuela A.,Mereiter, Kurt,Wang, Yaping,Weissensteiner, Walter
-
p. 3820 - 3832
(2015/08/24)
-
- Acceptor-substituted ferrocenium salts as strong, single-electron oxidants: Synthesis, electrochemistry, theoretical investigations, and initial synthetic application
-
A series of mono- and 1,1'-diheteroatom-substituted ferrocene derivatives as well as acylated ferrocenes was prepared efficiently by a unified strategy that consists of selective mono- and 1,1'-dilithiation reactions and subsequent coupling with carbon, phosphorus, sulfur and halogen electrophiles. Chemical oxidation of the ferrocene derivatives by benzoquinone, 2,3-dichloro-5,6- dicyanobenzoquinone, AgPF6, or 2,2,6,6-tetramethyl-1-oxopiperidinium hexafluorophosphate provided the corresponding ferrocenium salts. The redox potentials of the synthesized ferrocenes were determined by cyclic voltammetry, and it was observed that all new ferrocenium salts have stronger oxidizing properties than standard ferrocenium hexafluorophosphate. An initial application of selected derivatives in an oxidative bicyclization revealed that they mediate the transformation under considerably milder conditions than ferrocenium hexafluorophosphate. Quantum chemical calculations of the reduction potentials of the substituted ferrocenium ions were carried out by using a standard thermodynamic cycle that involved the gas-phase energetics and solvation energies of the contributing species. A remarkable agreement between theory and experiment was found: the mean average deviation amounted to only 0.030-V and the maximum deviation to 0.1-V. This enabled the analysis of various physical contributions to the computed reduction potentials of these ferrocene derivatives, thereby providing insight into their electronic structure and physicochemical properties. Copyright
- Khobragade, Dushant A.,Mahamulkar, Shraddha G.,Pospí?il, Lubomír,Císa?ová, Ivana,Rulí?ek, Lubomír,Jahn, Ullrich
-
supporting information
p. 12267 - 12277
(2012/11/14)
-
- Deprotonative metallation of ferrocenes using mixed lithium-zinc and lithium-cadmium combinations
-
A mixed lithium-cadmium amide and a combination of lithium and zinc amides were reacted with a range of ferrocenes; deprotonative mono- or dimetallation in general occurred chemoselectively at room temperature, as evidenced by subsequent quenching with iodine.
- Dayaker, Gandrath,Sreeshailam, Aare,Chevallier, Floris,Roisnel, Thierry,Radha Krishna, Palakodety,Mongin, Florence
-
p. 2862 - 2864
(2010/09/03)
-
- Ir-catalyzed C-H activation in the synthesis of borylated ferrocenes and half sandwich compounds
-
The complex generated from 1/2 [Ir(OMe)(cod)]2 and 4,4′-di-tert-butyl-2,2′-bipyridine catalyzes the regioselective borylation of ferrocenes, CpMn(CO)3 and CpMo(CO)3CH 3 with a stoichiometric amount of B2pin2.
- Datta, Anupama,Koellhofer, Axel,Plenio, Herbert
-
p. 1508 - 1509
(2007/10/03)
-
- The use of a modified Suzuki reaction for the synthesis of monoarylferrocenes
-
A modification of the Suzuki cross-coupling reaction proved to be a clean and useful method for the preparation of monosubstituted arylferrocenes. Iodoferrocene was reacted with a series of substituted arylboronic acids in the presence of sodium carbonate and palladium acetate in aqueous ethanol at room temperature to produce a range of substituted monoarylferrocenes. A systematic investigation undertaken to determine optimal reaction conditions indicated that scrupulous deoxygenation of the solvent is critical. The use of stronger bases such as barium hydroxide and potassium carbonate is favourable and gives rise to better yields of monoarylferrocenes. The reactions also proceed efficiently in aqueous DMF, broadening the scope of the reaction allowing efficient reactions with boronic acids that show low solubility in organic solvents.
- Imrie, Christopher,Loubser, Christa,Engelbrecht, Pieter,McCleland, Cedric W.
-
p. 2513 - 2523
(2007/10/03)
-
- N,N'-diferrocenyl-N-heterocyclic carbenes and their derivatives
-
In continuation of our work on Wanzlick/Arduengo carbenes containing redox-active ferrocenyl substituants we report on the synthesis of N,N'-diferrocenyl imidazol(in)ium salts as precursors of imidazol(in)-2-ylidenes. The necessary starting material for t
- Bildstein, Benno,Malaun, Michael,Kopacka, Holger,Wurst, Klaus,Mitterb?ck, Martin,Ongania, Karl-Hans,Opromolla, Giuliana,Zanello, Piero
-
p. 4325 - 4336
(2008/10/08)
-