Search results for "corroles"
showing 7 items of 7 documents
Efficient two-step synthesis of face-to-face meso-substituted bis(corrole) dyads
2008
The synthesis of face-to-face meso-substituted bis(corrole) systems was revisited. By using a new synthetic pathway, the reaction was generalized to any type of linker and the yield was considerably increased. The dyads were obtained in yields up to 20 % from a dialdehyde linker and dipyrromethane in a one-step reaction. The best reaction conditions required a decreased amount of TFA catalyst (1.4 equiv.) and a large excess of dipyrromethane (up to 8 equiv). Under these conditions, four bis(corrole)s linked by 2,2′-diphenyl ether, 9,9-dimethylxanthene, anthracene, and dibenzofuran spacers were synthesized.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Detection and monitoring of carbon monoxide using cobalt corroles film on Love wave devices with delay line configuration
2011
Among specific sensitive materials synthesized for chemical sensor development, cobalt corrole have shown attractive capabilities for CO detection [1, 2]. In this paper, we investigate the possibility to exploit such materials to develop surface acoustic wave (SAW)-based sensors. We actually demonstrate that SAW devices using delay line configuration allow investigating the molecular recognition occurring in non-conductive sensing layers of cobalt corroles. We have monitored phase variations of SAW devices versus various CO concentrations. Moreover, a specific testing setup has been developed to precisely dose CO at low concentrations, to avoid any CO leakage in the environment, to systemat…
Surface Acoustic Wave Sensors for the Detection of Hazardous Compounds in Indoor Air
2017
Presented at the Eurosensors 2017 Conference, Paris, France, 3–6 September 2017.; International audience; In this work, the authors show the capabilities of Surface Acoustic Wave (SAW) devices coupled with various absorbents to probe the properties of gas sensitive materials for the manufacturing of hazardous gas sensors. The great capabilities of cobalt corroles for the trapping of carbon monoxide (CO) were exploited to produce selective sensors. These corroles were deposited on SAW delay lines surfaces and then exposed to carbon monoxide (CO) in standard conditions. Concentrations of a few hundreds of ppb were measured emphasizing the interest of such sensors for the detection of CO. Anot…
Cobalt(IV) corroles as catalysts for the electroreduction of O2: reactions of heterobimetallic dyads containing a face-to-face linked Fe(III) or Mn(I…
2006
Abstract A series of heterobinuclear cofacial porphyrin–corrole dyads containing a Co(IV) corrole linked by one of four different spacers in a face-to-face arrangement with an Fe(III) or Mn(III) porphyrin have been examined as catalysts for the electroreduction of O 2 to H 2 O and/or H 2 O 2 when adsorbed on the surface of a graphite electrode in air-saturated aqueous solutions containing 1 M HClO 4 . The examined compounds are represented as (PCY)M III ClCo IV Cl where P is a porphyrin dianion, C is a corrole trianion and Y is a biphenylene (B), 9,9-dimethylxanthene (X), dibenzofuran (O) or anthracene (A) spacer. The catalytic behavior of the seven investigated dyads in the two heterobimet…
Selective chemisorption of carbon monoxide by organic-inorganic hybrid materials incorporating cobalt(III) corroles as sensing components.
2007
Twenty-one hybrid materials incorporating cobalt(III) corrole complexes were synthesized by a sol–gel process or by grafting the metallocorrole onto a mesostructured silica of the SBA-15 type. All the materials show an almost infinite selectivity for carbon monoxide with respect to dinitrogen and dioxygen in the low-pressure domain where the chemisorption phenomenon is predominant. This peculiar property is of prime importance for an application as a CO sensor. The selectivity slightly decreases at high pressures where nonselective physisorption phenomena mainly occur. The percentage of active sites for CO chemisorption ranges from 22 to 64 %. This low percentage may be attributable to inte…
Electrochemistry of Bis(pyridine)cobalt (Nitrophenyl)corroles in Nonaqueous Media
2018
International audience; A series of bis(pyridine)cobalt corroles with one or three nitrophenyl groups on the meso positions of the corrole macrocycle were synthesized and characterized as to their electrochemical and spectroscopic properties in dichloromethane, benzonitrile, and pyridine. The potentials for each electrode reaction were measured by cyclic voltammetry and the electron-transfer mechanisms evaluated by analysis of the electrochemical data combined with UV-visible spectra of the neutral, electroreduced, and electroxidized forms of the corroles. The proposed electronic configurations of the initial compounds and the prevailing redox reactions involving the electroactive central c…
Excited State N−H Tautomer Selectivity in the Singlet Energy Transfer of a Zinc(II)-Porphyrin-Truxene-Corrole Assembly
2017
International audience; An original corrole-containing polyad for S-1 energy transfer, in which one zinc(II)-porphyrin donor is linked to two free-base corrole acceptors by a truxene linker, is reported. This polyad exhibits a rapid zinc(II)-porphyrin*free-base corrole transfer (4.83x10(10)s(-1); 298K), even faster than the tautomerization in the excited state processes taking advantage of the good electronic communication provided by the truxene bridge. Importantly, the energy transfer process shows approximately 3-fold selectivity for one corrole N-H tautomer over the other even at low temperature (77K). This selectivity is due to the difference in the J-integral being effective in both t…