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31.
In this work, the electrochemical behavior of ferrocene (Fc) was investigated by cyclic voltammetry (CV) in room temperature ionic liquids (RTILs) of 1‐ethyl‐3‐methylimidazolium tetrafluoroborate (EMIBF4) on glass carbon (GC), edge plane pyrolytic graphite (EPPG) and multi‐walled carbon nanotube (MWCNTs)‐modified EPPG electrodes, respectively. The results demonstrated that on GC electrode, pairs of well‐defined reversible peaks were observed, while for the electrode of EPPG, the peak potential separation (ΔEp) is obviously larger than the theoretical value of 59 mV, hinting that the electrode of EPPG is distinguished from the commonly used electrode, consistent with the previous proposition that EPPG has many “defects”. To obtain an improved electrochemical response, multi‐walled carbon nanotubes (MWCNTs) were modified on the electrode of EPPG; the increased peak current and promoted peak potential separation not only proved the existence of “defects” in MWCNTs, but also supported that “creating active points” on an electrode is the main contribution of MWCNTs. Initiating the electrochemical research of Fc on the MWCNTs‐modified EPPG electrode in RTILs and verifying the presence of “defects” on both EPPG and MWCNTs using cyclic voltammograms (CVs) of Fc obtained in RTILs of EMIBF4, is the main contribution of this preliminary work. 相似文献
32.
Bruno Therrien Ludovic Vieille-Petit Petr Štěpni?ka Georg Süss-Fink 《Journal of organometallic chemistry》2004,689(15):2456-2463
A series of arene-ruthenium complexes of the general formula [RuCl2{η6-C6H5(CH2)2R}L] with R=OH, CH2OH, OC(O)Fc, CH2OC(O)Fc (Fc=ferrocenyl) and L=PPh3, (diphenylphosphino)ferrocene, or bridging 1,1′-bis(diphenylphosphino)ferrocene, have been synthesized. Two synthetic pathways have been used for these ferrocene-modified arene-ruthenium complexes: (a) esterification of ferrocene carboxylic acid with 2-(cyclohexa-1,4-dienyl)ethanol, followed by condensation with RuCl3 · nH2O to afford [RuCl2{η6-C6H5(CH2)2OC(O)Fc}]2, and (b) esterification between ferrocene carboxylic acid and [RuCl2{η6-C6H5(CH2)3OH}L] to give [RuCl2{η6-C6H5(CH2)3OC(O)Fc}L]. All new compounds have been characterized by NMR and IR spectroscopy as well as by mass spectrometry. The single-crystal X-ray structure analysis of [RuCl2{η6-C6H5(CH2)3OH}(PPh3)] shows that the presence of a CH2CH2CH2OH side-arm allows [RuCl2{η6-C6H5(CH2)3OH}(PPh3)] to form an intramolecular hydrogen bond with a chlorine atom. The electrochemical behavior of selected representative compounds has been studied. Complexes with ferrocenylated side arms display the expected cyclic voltammograms, two independent reversible one-electron waves of the Ru(II)/Ru(III) and Fe(II)/Fe(III) redox couples. Introduction of a ferrocenylphosphine onto the ruthenium is reflected by an additonal reversible, one-electron wave due to ferrocene/ferrocenium system which is, however, coupled with the Ru(II)/Ru(III) redox system. 相似文献
33.
Méndez I. Daniel Klimova Elena Perez F. Javier 《Journal of organometallic chemistry》2004,689(15):2503-2510
The Wittig olefination of ferrocene-containing chalcones leads to 1,3-dienes and their cyclodimers. The reaction of 1,3-dienes with dibromocarbene yields gem-dibromo(ferrocenylvinyl)cyclopropanes. Upon reductive dehalogenation with ethylmagnesium bromide they afford the corresponding monobromo derivatives. All the obtained compounds were characterized by 1H and 13C NMR, elemental analysis, and mass spectrometry. The structures of compounds 5a,b, 6g, 6h, and 7i were confirmed by X-ray diffraction analysis. 相似文献
34.
Stéphane Campidelli Julián Rodríguez-López Fernando Langa Robert Deschenaux 《Tetrahedron》2006,62(9):2115-2122
First- and second-generation ferrocene-based dendrimers, fullerene and a second-generation liquid-crystalline poly(arylester) dendrimer carrying four cyanobiphenyl units were assembled to elaborate polyfunctional materials displaying mesomorphic and electronic properties. The targeted compounds gave rise to enantiotropic smectic A phases and organized into bilayer structures within the smectic layers. Cyclic voltammetry investigations revealed oxidation and reduction processes in agreement with the presence of both ferrocene and fullerene units. Finally, strong quenching of the fluorescence was obtained for the fullerene-ferrocene dyads suggesting efficient elecron transfer from the ferrocene-based dendrimer to fullerene. 相似文献
35.
Neil Bricklebank Simon J. Coles Michael B. Hursthouse Peter J. Skabara 《Journal of organometallic chemistry》2005,690(2):328-332
The title compound, Fc2(Ph)PS · I2, has been prepared and characterised in both the solid state and solution. Single crystal X-ray crystallography reveals that the adduct adopts a molecular charge-transfer structure in the solid state. Mössbauer spectroscopy confirms the presence of low spin Fe2+ but also indicates the presence of ca. 24% of an Fe3+ species. The electrochemistry of Fc2(Ph)PS · I2, Fc2(Ph)PS and Fc2(Ph)P has been studied using a combination of cyclic voltammetry and differential pulse voltammetry. The data for Fc2(Ph)PS · I2 show two redox processes, consistent with the sequential oxidation of the ferrocenyl groups to ferrocenium species. 相似文献
36.
《Electroanalysis》2005,17(20):1865-1869
A novel anion‐selective PVC membrane electrode based on bis‐[(3‐ferrocenyl)‐(2‐crotonic acid)] copper(II) complex [Cu(II)‐BFCA] as neutral carrier is described, which demonstrates excellent potentiometric response characteristics toward thiocyanate ion and anti‐Hofmeister selectivity sequence in following order: SCN?>I?>ClO >Sal?>Br?>NO >Cl?≈NO >SO >SO . The electrode shows a near‐Nernstian response for thiocyanate ion in a wide range of 9.0×10?7–1.0×10?1 M with a detection limit 6.8×10?7 M and a slope of ?59.1 mV/decade in pH 5.0 of phosphate buffer solution at 20 °C. The influences of lipophilic cationic and anionic additives on the response properties of the electrode were investigated. High sensitivity and wide linear dynamic range were observed for the electrode in the presence of hexadecyltrimethylammoniumborate (HTAB) as a lipophilic cationic additive. The electrode was successfully applied to the determination of thiocyanate ion in waste water and human saliva. 相似文献
37.
Bernd Schetter 《Journal of organometallic chemistry》2004,689(9):1472-1480
N,N′-dicyclohexyl-N-ferrocenoylurea 2, N,N′-diisopropyl-N-ferrocenoylurea 3, N,N′-di-p-tolyl-N-ferrocenoylurea 4 and N,N′-di-tert-butyl-N-ferrocenoylurea 5 were obtained by reaction of ferrocenecarboxylic acid 1 with N,N′-dicyclohexylcarbodiimide (DCC), N,N′-diisopropylcarbodiimide (DIC), N,N′-di-p-tolylcarbodiimide 10 and N,N′-di-tert-butylcarbodiimide 11, respectively. Both N-tert-butyl-N′-ethyl-N-ferrocenoylurea 6 and N′-tert-butyl-N-ethyl-N-ferrocenoylurea 7 were obtained by reaction of 1 with N-tert-butyl-N′-ethylcarbodiimide 12. In all cases a small amount of ferrocenecarboxylic anhydride 8 was formed as a by-product. All compounds were characterized by 1H NMR, 13C NMR, IR and MS. Single crystal X-ray structural analyses were made of 2, 3 and 4. From the consistent results, the reaction products of 1 with carbodiimides appear different from those proposed by some earlier workers. With N-(3-dimethylaminopropyl)-N′-ethylcarbodiimidehydrochloride 9 ferrocenoylurea was not isolated, but the main product was rather 8. The suitability of 8 as acylation reagent was applied by using 9 to obtain N-(3-triethoxysilyl)-propylferrocenecarboxamide in a one-pot reaction from 1 and 3-(triethoxysilyl)-propylamine. 相似文献
38.
《Journal of organometallic chemistry》2004,689(20):3232-3241
Cationic cycloaddition of cross-conjugated 3-ferrocenylmethylidene-2,4-dimethylpenta-1,4-diene to 1-ferrocenyl-2-isopropenyl-3,3-dimethylallylium tetrafluoroborate and its proton-catalyzed cyclodimerization result in diferrocenylbicyclo[3.3.1]nonene derivatives. The spatial structure of one of the reaction products, viz., ferroceno[4,5]-{9-ferrocenylmethylidene-1,3,3,8,10-pentamethyltricyclo[6.3.1.02,6]dodec-2(6)-ene}, was established based on the data from X-ray diffraction analysis. 相似文献
39.
Synthesis and biological activity research of novel ferrocenyl-containing thiazole imine derivatives
Haibo Yu 《Journal of organometallic chemistry》2007,692(5):991-996
A series of novel N-substituted benzylidene-4-ferrocenyl-5-(1H-1,2,4-triazol-1-yl)-1,3-thiazol-2-amine derivatives were synthesized by condensation of substituted-benzaldehydes with 2-amino-4-ferrocenyl-5-(1H-1,2,4-triazol-1-yl)-1,3-thiazole and characterized by 1H NMR, X-ray diffraction and elemental analysis. The results of bioassay showed that some title compounds exhibited some degree of plant growth regulatory and antifungal activities. 相似文献
40.
二茂铁化学修饰电极测定丙二醛的研究 总被引:4,自引:0,他引:4
报道了在玻碳电极上共价键合二茂铁的新型化学修饰电极。研究了该电极对丙二醛的电催化作用。以微分脉冲伏安法测定丙二醛,方法具有较好的灵敏度和选择性。丙二醛的峰电流与其浓度在20×10-6~20×10-3mol/L呈良好的线性关系。 相似文献