1273-82-1Relevant academic research and scientific papers
A switchable electrochemical redox ratiometric substrate based on ferrocene for highly selective and sensitive fluoride detection
Manibalan, Kesavan,Mani, Veerappan,Huang, Sheng-Tung
, p. 71727 - 71732 (2016)
A novel latent electrochemical probe based on a ferrocenyl carbamate derivate (FCCD) was synthesized for the highly selective ratiometric detection of fluoride (F-). FCCD was synthesized through an easy, one step reaction using ferrocenyl azide and silyl protected benzyl alcohol as precursors through a Curtius rearrangement. In presence of F-, FCCD undergoes a nucleophilic substitution reaction, which led to the removal of silyl protecting group through 1,6-quinone-methide rearrangement with concomitant release of ferrocenyl amine (FA). As the concentration of F- increases, the amount of FCCD is dissipated, while that of FA accumulated in the reaction medium were monitored through the linear changes in their redox couples. Compared with a conventional ion selective electrode, the use of a cheaper unmodified electrode as a transducer coupled with FCCD displayed higher stability, excellent selectivity and better sensitivity with LOD of 5.1 × 10-7 M (9.69 ppb). Moreover, FCCD is a selective and sensitive colorimetric visualization probe for F-. The proof-of-concept of the approach is demonstrated in direct toothpaste sample (non-transparent solutions), biological and water samples. The important advantages of this approach are high selectivity, the use of cheaper unmodified electrode, adoption of simple electrochemical methods, dual channel detection, low overpotential of the reporter, naked-eye detection, and ability to detect F- in non-transparent samples.
Synthesis and conformational study of bioconjugates derived from 1-acetyl-1′-aminoferrocene and α-amino acids
Semen?i?, Mojca ?aki?,Kova?, Veronika,Kodrin, Ivan,Bari?i?, Lidija,Rapi?, Vladimir
, p. 112 - 123 (2015)
1,1′-Disubstituted ferrocene conjugates present useful and efficient bioorganometallic constraint design to reduce the conformational flexibility of small peptides. In this study we present the first systematic conformational analysis of nonsymmetric ferrocene peptidomimetics (Boc-AA-NH-Fn-COMe; Boc = tert-butoxycarbonyl; AA = Gly, L-Ala, L-Val; Fn = 1,1′-ferrocenylene) and their monosubstituted analogues (Boc-AA-NH-Fc; Fc = ferrocenyl; AA = Gly, L-Ala, L-Val). The spectroscopic data (IR, NMR and CD) were corroborated by DFT calculations and indicated the engagement of the NH group closest to the ferrocene unit in intrachain hydrogen bonds. This medium-strength bond is not disrupted by the introduction of a hydrogen-bonding acceptor on the other ferrocene ring, but rather is accompanied by an additional interchain hydrogen bond, which causes the restricted rotation of ferrocene rings and gives rise to a chiral arrangement of the ferrocene core in a P helical manner.
Observation of a large current on the cyclic voltammetry of acylaminoferrocenes in the solid state: An efficient electron-transfer pathway through continuous NH...O=C hydrogen-bond chains and π-conjugation
Okamura, Taka-Aki,Sakauye, Keiko,Doi, Mototsugu,Yamamoto, Hitoshi,Ueyama, Norikazu,Nakamura, Akira
, p. 1270 - 1278 (2005)
A series of crystal structures of acylaminoferrocenes, [(C 5H5)Fe(C5H4NHCOR)] (R = CH 3 (1), CH2CH3 (2), t-Bu (3), and CF3 (4)) revealed an unusually delicate dependence of the alkyl substituent structure on electron transfer through NH...O=C bonding and π-conjugation. The presence of strong intermolecular NH...O=C hydrogen bonds in the crystal was established by X-ray, IR, and CRAMPS. Compounds 1 and 2 are without steric or electrostatic hindrance, and both exhibit continuous and strong hydrogen-bond chains, or an effective π-electrons system. However, the hydrogen-bond chains in 3 and 4 are weak, or broken, by the bulkiness of t-Bu or the electrostatic repulsion of CF3. Solid-state cyclic voltammograms of 1-4 have revealed the electrochemical processes, which are critically dependent on the array and the strength of the hydrogen bonds. Although both 3 and 4 show typical reversible cyclic voltammograms, 1 and 2 exhibit irreversible redox behaviors and remarkably large current values, which indicate the presence of an effective electron transfer through the continuous hydrogen-bond chains.
Main chain ferrocenyl amides from 1-aminoferrocene-1′-carboxylic acid
Heinze, Katja,Schlenker, Manuela
, p. 2974 - 2988 (2004)
The non-natural amino acid 1-aminoferrocene-1′-carboxylic acid is synthesised from ferrocene in eight steps. The folding and association phenomena of amido-substituted ferrocenes in the crystal as well as in solution are studied by X-ray crystallography, IR and NMR spectroscopy and DFT calculations. The amino acid is selectively protected at the amino group with the use of the fluorenyl-9-methoxycarbonyl (Fmoc) group. An amide-linked ferrocene dimer is prepared using the HOBt/DCC protocol for amide formation. In the crystal the dimer forms a hydrogen-bonded sheet structure, while in solution dynamic intramolecular hydrogen bonds are observed by VT 1H NMR and IR spectroscopy. The dynamic flipping process has been rationalised by DFT calculations. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004.
A versatile ferrocene-containing material as a p-type charge generation layer for high-performance full color tandem OLEDs
Chang, Yu-Wei,Huang, Min-Jie,Lai, Cheng-Chang,Chang, Ching-Chih,Huang, Man-Ping,Liao, Chuang-Yi,Cheng, Chien-Hong
, p. 14294 - 14297 (2016)
A novel p-type charge generation material, DPAF, composed of a ferrocene core and a bis(biphenyl)amino group is designed and synthesized for application to tandem OLED devices. This molecular design not only enhances the thermal properties of ferrocene and the hole mobility, but also maintains its electrochemical stability. The red, green, and blue tandem OLEDs all give excellent device performance with low efficiency roll-off by using n-type C60 and p-type DPAFs as charge generation layers.
Ratiometric electrochemical detection of Pd???π interactions: application towards electrochemical molecular logic gates
Goggins, Sean,Stark, Oliver P.,Naz, Christophe,Marsh, Barrie J.,Frost, Christopher G.
, p. 749 - 757 (2017)
The widespread and large scale use of platinum group metals, especially palladium, in a wide variety of industrial applications has seen their levels in wastewater streams, roadside dust and even pharmaceuticals significantly rise over recent years. Due to the possible environmental damage and potential health risk this may cause, there is now substantial demand for inexpensive, efficient and robust methods for the detection of palladium. Based upon self-immolative linker technologies, we have designed and synthesised a number of allyl ether-functionalised electrochemical probes to determine the optimum probe structure required to deliver a ratiometric electrochemical detection method capable of achieving a limit of detection of?a proof-of-principle ratiometric electrochemical molecular logic gate.
Combining ferrocene, thiophene and a boronic acid: A hybrid ligand for reagentless electrochemical sensing of cis-diols
Lacina, Karel,Konhefr, Martin,Novotny, Jan,Potě?il, David,Zdráhal, Zbyněk,Skládal, Petr
, p. 3235 - 3238 (2014)
A redox-active affinity ligand suitable for reagentless sensing of cis-diols was synthesised and characterised. 4-[(Ferrocenylamino)methyl] thiophene-3-boronic acid (FcTBA) was allowed to interact with the model cis-diol, sorbitol. A discrete, cathodic shift of the redox potential was observed upon interaction of FcTBA with sorbitol thus providing simultaneous differentiation between the free and bound forms of this sensor molecule. Similar behaviour was observed also for FcTBA co-immobilised with thiophene in a mixed self-assembled monolayer on a gold electrode.
Aluminum complexes with new non-symmetric ferrocenyl amidine ligands and their application in CO2 transformation into cyclic carbonates
Rios Yepes, Yersica,Martínez, Javier,Rangel Sánchez, Hiram,Quintero, Celso,Ortega-Alfaro, M. Carmen,López-Cortés, José G.,Daniliuc, Constantin G.,Anti?olo, Antonio,Ramos, Alberto,Rojas, René S.
, p. 1124 - 1134 (2020)
A set of alkyl aluminum complexes supported by non-symmetric ferrocenyl amidine ligands were used as catalysts for the preparation of cyclic carbonates from epoxides and carbon dioxide using Bu4NI as a co-catalyst. A modified method for the synthesis of aminoferrocene allowed us to obtain this precursor in quantitative yield. Treatment of aminoferrocene with the corresponding acetimidoyl chloride afforded the desired ferrocenyl amidine ligands L1H, (E)-N-(2,6-diisopropylphenyl)-N'-(ferrocenyl)acetimidamide, and L2H, (E)-N-(2,6-dimethylphenyl)-N'-(ferrocenyl)acetimidamide. The reaction of these ligands with 1.0 or 0.5 equiv. of AlMe3 led to the synthesis of aminoferrocene based aluminum complexes ((L1)AlMe2 (1), (L2)AlMe2 (2), (L1)2AlMe (3), and (L2)2AlMe (4)) in excellent yields, which were characterized by spectroscopic and X-ray diffraction methods. In addition, we have studied their electrochemical properties and complex 1 was found to be the most active catalyst for the formation of cyclic carbonates 6a-j from their corresponding epoxides 5a-j and CO2.
Triferrocenes built on a C3-symmetric ligand platform: Entry to redox-active pseudo-triphenylenes via chelation-driven stereoselection of triple Schiff bases
Lim, Young-Kwan,Wallace, Scott,Bollinger, John C.,Chen, Xufang,Lee, Dongwhan
, p. 1694 - 1703 (2007)
An expedient tandem deprotonation-trapping protocol was employed to prepare a tris(difluoroboronyl) complex of a triferrocenyl ligand that is geometrically analogous to substituted triphenylenes. A triple Schiff base condensation reaction between 1,3,5-triformylphloroglucinol and aminoferrocene afforded the tris(N-salicylideneamine) adducts 5a + 5b in ca. 1:1 ratio. The keto-enamine tautomeric core of this isomeric mixture could be converted to a common enolate-imine intermediate. Subsequent trapping with BF3· Et2O cleanly afforded the tris(difluoroboronyl) adduct 6 in essentially quantitative yield. The electronic and structural properties of this new class of ferrocene compounds were investigated using various methods including UV-vis, cyclic voltammetry (CV), differential pulse voltammetry (DPV), and X-ray crystallography. In CH2Cl2-CH3CN, 6 displayed a reversible three-electron oxidation process at E1/2 ox = +210 mV (vs Fc/Fc+). Despite the sharing of a common [π,π]/[π,π]-conjugated core, no significant electronic communication was observed among the three ferrocenyl units in 6 under either CV or DPV conditions. On the other hand, the broad oxidation wave of 5a + 5b at E 1/2ox = +60 mV in CH2Cl2-CH 3CN was comprised of at least two major components at +20 and +90 mV, which collapsed to become a single peak in DMF electrolyte, despite that the ratios between the two isomers 5a,b remained essentially invariant to the change in solvent.
N-ferrocenyl-substituted planar-chiral N-heterocyclic carbenes and their PdII complexes
Bertogg, Andreas,Camponovo, Francesco,Togni, Antonio
, p. 347 - 356 (2005)
The N-ferrocenyl-linked N-heterocyclic carbenes 1a and 1b were obtained by treatment of their imidazolium salts 12a and 12b with potassium tert-butoxide. The latter were shown to be accessible from (R)-1-amino-2-methylferrocene (9) and aminoferrocene, respectively, which were converted into the corresponding formamidines and then subjected to a novel cyclization procedure. Treating the ligand precursors 12a and 12b with [Pd(OAc)2]3 under different reaction conditions afforded the trans-pyridine-substituted Pd II complexes 14a and 14b as well as their trans-triphenylphosphane- substituted counterparts 16a and 16b and, in the case of the chiral ligand precursor, the dinuclear PdII complex 15a. Conformational analysis of the ligands based on the X-ray structures of 12a, 12b and 16a revealed the dependence of the two torsion angles between the central imidazolium core and the adjacent ferrocenyl substituents on the steric and electronic properties of the observed systems. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005.
