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Jan Becher - One of the best experts on this subject based on the ideXlab platform.
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Pyrrolo‐Tetrathiafulvalenes and Their Applications in Molecular and Supramolecular Chemistry
European Journal of Organic Chemistry, 2003Co-Authors: Jan O. Jeppesen, Jan BecherAbstract:Although Tetrathiafulvalene and its derivatives have been extensively studied as π-electron donors in the fields of molecular organic metals and electrically conducting materials for more than 30 years, the intriguing potential of Tetrathiafulvalene as a building block in molecular and supramolecular chemistry has only recently been developed. Progress in synthetic Tetrathiafulvalene chemistry has enabled the preparation of elaborate molecular architectures and, in recent years, Tetrathiafulvalene has been incorporated into a number of molecular and supramolecular systems. In this microreview we describe the background to our interest in the development of the parent pyrrolo-Tetrathiafulvalenes, followed by a journey through their applications in macrocyclic, molecular, and supramolecular chemistry. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
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A pyrrolo-Tetrathiafulvalene cage: synthesis and X-ray crystal structure.
Organic letters, 2002Co-Authors: Kent A. Nielsen, Eric Levillain, Jan O. Jeppesen, Niels Thorup, Jan BecherAbstract:[reaction: see text] A novel type of Tetrathiafulvalene-cage 4 containing three monopyrrolo-Tetrathiafulvalene units has been prepared employing a general and efficient synthetic approach. X-ray crystal structure analysis revealed that the cage is able to accommodate solvent molecules within a cavity in the solid state.
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Electrochemical Recognition of Cations by Bis(pyrrolo)Tetrathiafulvalene Macrocycles
Organic letters, 2002Co-Authors: Gaëlle Trippé, Eric Levillain, Marc Sallé, Alain Gorgues, Jan O. Jeppesen, Kent A. Nielsen, Franck Le Derf, Jan BecherAbstract:Tetrathiafulvalene redox-responsive ligands devoid of cis/trans isomerism containing the electroactive bis(pyrrolo[3,4-d])Tetrathiafulvalene moiety and polyether subunits have been synthesized. One ligand exhibits high binding affinities for Pb2+ and Ba2+ cations as shown by independent methods (1H NMR, UV−vis spectroscopy, and cyclic voltammetry). The ability of this receptor to electrochemically recognize Pb2+ and Ba2+ is shown by cyclic voltammetry.
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A pyrrolo-Tetrathiafulvalene belt and its TCNQ complex: syntheses and X-ray crystal structures.
Organic letters, 2002Co-Authors: Kent A. Nielsen, Jan O. Jeppesen, Niels Thorup, Jan BecherAbstract:A general and efficient four-step synthesis of a Tetrathiafulvalene-belt 6, starting from the monopyrrolo-Tetrathiafulvalene building block 1, is described, together with its 7,7,8,8-tetracyano-p-quinodimethane charge transfer complex. The complexation of the electron acceptor 7,7,8,8-tetracyano-p-quinodimethane by the Tetrathiafulvalene-belt 6 was investigated both in solution and in the solid state.
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Pyrrolo-annelated Tetrathiafulvalenes: the parent systems
The Journal of organic chemistry, 2000Co-Authors: Jan O. Jeppesen, Kazuo Takimiya, Frank Jensen, Thomas Brimert, Kent A. Nielsen, Niels Thorup, Jan BecherAbstract:The synthesis of a number pyrrolo-annelated Tetrathiafulvalenes, including the parent bis(pyrrolo[3,4-d])Tetrathiafulvalene (7) is decribed. Starting from readily available 4,5-bis(bromomethyl)-1, 3-dithiole-2-thione (14) and sodium tosylamide, the parent 7 and the asymmetric monopyrrolo Tetrathiafulvalenes 23a,b were prepared in good yields via a nonclassical and simple pyrrole synthesis. Furthermore, a series of asymmetrical N-alkylated monopyrrolo/monodihydropyrroloTetrathiafulvalenes was prepared starting from primary amines and 14. A detailed study of the fundamental redox behavior of this class of heterocycles is reported. NMR spectroscopy, cyclic voltammetry, and PM3 MO calculations revealed that the pyrrolo-annelated Tetrathiafulvalenes have highly extended pi-surfaces. The X-ray crystallographic analyses of the monopyrrolo Tetrathiafulvalenes 22b and 24b, together with preliminary formation of a charge-transfer complex between the parent donor 7 and TCNQ, are also reported.
Narcis Avarvari - One of the best experts on this subject based on the ideXlab platform.
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Radical cation salts of BEDT-TTF, enantiopure tetramethyl-BEDT-TTF, and TTF-Oxazoline (TTF-Ox) donors with the homoleptic TRISPHAT anion
New Journal of Chemistry, 2011Co-Authors: François Riobé, Flavia Piron, Céline Réthoré, Augustin M. Madalan, Carlos J. Gómez-garcía, Jérôme Lacour, John D. Wallis, Narcis AvarvariAbstract:The synthesis and crystal structures of five radical cation salts based on the organic donors bis(ethylenedithio)Tetrathiafulvalene (BEDT-TTF), racemic ethylenedithio-methyl-oxazoline-Tetrathiafulvalene (EDT-TTF-MeOx) and the enantiopure (S,S,S,S) and (R,R,R,R) tetramethyl-bis(ethylenedithio)Tetrathiafulvalene (TMBEDT-TTF) and the D3-symmetric anion tris(tetrachlorobenzenediolato)phosphate(V) (TRISPHAT) are reported. The salts are formulated as [BEDT-TTF][(rac)-TRISPHAT]·CH2Cl2 (1), [BEDT-TTF][(rac)-TRISPHAT]·2CH3CN (2), [(rac)-EDT-TTF-Ox][(rac)-TRISPHAT]·CH3CN (3), [(S,S,S,S)-TMBEDT-TTF][(rac)-TRISPHAT]·2CH3CN (4), and [(R,R,R,R)-TMBEDT-TTF][(rac)-TRISPHAT]·2CH3CN (5). The donors are fully oxidized and self-assemble in dyads inserted in the channels generated by the packing of the TRISPHAT anions. Magnetic and EPR measurements performed on compounds 1 and 2 clearly indicate weak interactions within the dimers in compound 1, characterized by a very narrow line in the EPR spectrum, while the radicals are strongly coupled in compound 2.
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Bis(dithiomethyl-Tetrathiafulvalene) with two phenyl-phosphino bridges
Comptes Rendus Chimie, 2010Co-Authors: Ion Danila, Narcis AvarvariAbstract:Abstract The single crystal X-ray structure of the precursor dithiomethyl-Tetrathiafulvalene (MeS)2TTF is reported, together with theoretical calculations at DFT level, which afforded two energy minima corresponding to cis and trans orientations of the thiomethyl substituents. The bis(Tetrathiafulvalene) reaction of this TTF derivative followed by the reaction with phenyldichlorophosphine provides a new rigid bis(Tetrathiafulvalene [TTF]) containing a 1,4-dihydro-1,4-diphosphinine ring between the two redox active units. Its solid-state structure, determined by single crystal X-ray diffraction analysis, shows the coexistence of both cis and trans isomers. Cyclic voltammetry measurements are in accordance with the existence of a communication between the two TTFs, as illustrated by the splitting of the oxidation waves.
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Tetrathiafulvalene based group xv ligands synthesis coordination chemistry and radical cation salts
Coordination Chemistry Reviews, 2009Co-Authors: Dominique Lorcy, Marc Fourmigué, Nathalie Bellec, Narcis AvarvariAbstract:This review deals with the synthesis, properties and applications of metal complexes of Tetrathiafulvalene-based group XV (N, P, As, Sb) ligands. The different synthetic methods for the preparations of Tetrathiafulvalenes (TTFs) incorporating coordination functions such as N atoms (essentially sp2 N atoms in pyridines, pyrazines, bipyridines, imines, etc.) and P atoms (essentially in tertiary phosphines) are reviewed, together with the redox properties of these free ligands, showing in most cases that the electron donating ability of the TTF core is only scarcely affected upon association with the coordinating group. Metal complexes of such ligands have been reported with a large variety of metal centers, from group 6 (Cr, Mo, W) to group 12 (Zn, Cd, Hg). Their structural and electronic and magnetic properties are described, with an emphasis on the evolution of the properties of the ligand (redox potentials, 31P NMR chemical shifts) upon coordination. Two applications of these complexes are further discussed, elaboration of multi-functional conducting materials upon TTF oxidation, redox modulation of the reactivity of the metal complex used as catalyst.
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Tetrathiafulvalene-Oxazolines (TTF-Ox) And Derivatives: Valuable Precursors For Chiral Conductors And Electroactive Complexes
Revue Roumaine de Chimie, 2009Co-Authors: Narcis AvarvariAbstract:The synthesis and structural characterization of racemic and enantiopure Tetrathiafulvalene-oxazolines (TTF-OX) derivatives, with an emphasis on several key features, are reviewed. These compounds can serve as precursors for conducting chiral materials, but also as electroactive ligands for transition metal complexes. Crystalline conducting molecular materials have been obtained uponelectrocrystallization of some of the donors, such as the first complete series of mixed-valence metallic salts based on chiral Tetrathiafulvalenes, bearing the (R)-, (S)-, or racemic (±)-methyl–oxazoline heterocycle and the AsF6– monoanion. Transition metal complexes containing electroactive TTF-OX ligands have been prepared as well. Palladium and iridium complexes containing TTF-phosphino-oxazoline (TTF-PHOX) ligands have been applied in two homogeneous catalytic processes.
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Selective monosulfoxidation of Tetrathiafulvalenes into chiral TTF-sulfoxides.
Chirality, 2009Co-Authors: Marcos Chas, François Riobé, Raquel Sancho, Cristina Minguillón, Narcis AvarvariAbstract:Four inner Tetrathiafulvalene-sulfoxides have been synthesized upon reaction of Tetrathiafulvalene (TTF), tetramethyl-Tetrathiafulvalene (TMTTF), tetrakis (thiomethyl)-Tetrathiafulvalene (TMT-TTF), and bis(ethylenedithio)-Tetrathiafulvalene (BEDT-TTF) with enantiopure (+) or (−)-(8,8-dichlorocamphorylsulfonyl)-oxaziridine as oxidizing agent. Chiral HPLC studies indicate very weak enantioselectivities for TTF-SO 3 and TMTTF-SO 4, formation of racemic mixture in the case of TMT-TTF-SO 5, and a rather good selectivity, up to 44% ee, in the case of BEDT-TTF-SO 1. The solid state structures of TMTTF-SO 4 and TMT-TTF-SO 5 have been determined by single crystal X-ray diffraction. Both compounds crystallize as racemates in the centrosymmetric triclinic space group P-1. Theoretical calculations at DFT/B3LYP/6-31+G* level afford optimized geometries in good accordance with the experimental structures and emphasize the participation of the chiral sulfoxide group in HOMO and LUMO. Time-dependent DFT calculations corroborated with electronic circular dichroism spectra allow the assignment of the absolute configuration (R) for the major enantiomer of 1 when the (+)-sulfonyl-oxaziridine is used as oxygen transfer reagent. Preliminary semipreparative HPLC separation provided enantioenriched fractions up to 63% ee. Chirality, 2009. © 2009 Wiley-Liss, Inc.
Jan O. Jeppesen - One of the best experts on this subject based on the ideXlab platform.
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Tetrathiafulvalene Porphyrins
Chemistry - A European Journal, 2009Co-Authors: Kent A. Nielsen, Eric Levillain, Vincent M. Lynch, Jonathan L. Sessler, Jan O. JeppesenAbstract:Four Tetrathiafulvalene (TTF)-annulated porphyrins 1–4 were synthesized and characterized. All contain a tetraphenylporphyrin (TPP) core onto which four, two, or one TTF subunits were annulated. Absorption and fluorescence spectroscopic studies together with electrochemical investigations reveal that interactions between the porphyrin system and the annulated TTF units take place in solution. The annulation of one or more TTF units to the porphyrin core has a profound effect on the reduction potentials associated with this latter framework, with positive shifts in the range of 0.105 to 0.355 V and 0.200 to 0.370 V for the first and second reduction potential, respectively, compared to the corresponding processes in the model compound TPP, 18. The redox potentials for the first oxidation of the TTF units are considerably shifted in 4 (ΔEox1=+0.285 V) and 2 (ΔEox1=−0.140 V), whereas for 1 and 3 these potentials remain within the region expected for a normal TTF unit. Considerable changes in the second oxidation potential associated with the TTF subunits were seen for 2 (ΔEox1=−0.085) and 3 (ΔEox1=−0.175). The emission spectra of 1–4 revealed that the porphyrin fluorescence is almost quenched in the neutral state of the TTF-annulated porphyrins, a finding that is consistent with substantial electron transfer taking place from the TTF subunits to the porphyrin core. Oxidation of the TTF unit(s) (TTF→TTF.+) present in 1–4 leads to the emission intensity being restored.
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Cis- and trans-bis(2-cyanoethylsulfanyl)(decane-1,10-diyldithio)Tetrathiafulvalene.
Acta crystallographica. Section C Crystal structure communications, 2006Co-Authors: Sune Nygaard, Jan O. Jeppesen, Amar H Flood, Andrew D BondAbstract:The isomeric title compounds, 2,7-bis(2-cyanoethylsulfanyl)-3,6-(decane-1,10-diyldithio)Tetrathiafulvalene and 2,6-bis(2-cyanoethylsulfanyl)-3,7-(decane-1,10-diyldithio)Tetrathiafulvalene, both C22H28N2S8, comprise bis(2-cyanoethylsulfanyl)Tetrathiafulvalene units tethered by a saturated decamethylenedithio linker attached in either a cis or a trans manner. The Tetrathiafulvalene (TTF) group is planar in the cis isomer, but distorted significantly from planarity and twisted about its long axis in the trans isomer. In both structures, intermolecular interactions are segregated into regions in which TTF units are brought into close contact and regions where the polymethylene chains are brought into close contact. In the cis isomer, TTF units exhibit pi-pi stacking interactions, while in the trans isomer they do not.
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Tetrathiafulvalene-calix[4]pyrroles: synthesis, anion binding, and electrochemical properties.
Journal of the American Chemical Society, 2006Co-Authors: Kent A. Nielsen, Eric Levillain, Won-seob Cho, Joel Lyskawa, Vincent M. Lynch, Jonathan L. Sessler, Jan O. JeppesenAbstract:The syntheses of monoTetrathiafulvalene-calix[4]pyrrole 5 and bisTetrathiafulvalene-calix[4]pyrrole 6, prepared from the acid-catalyzed condensation of monopyrrolo[3,4-d]Tetrathiafulvalene (MPTTF, 7) with acetone in the presence of tripyrrane 8 and dipyrromethane 9, respectively, are described. Compound 5 and the previously reported Tetrathiafulvalene-calix[4]pyrrole 4 both adopt a 1,3-alternative conformation in the solid state, as determined from X-ray crystallographic analysis. The anion binding properties of the Tetrathiafulvalene-calix[4]pyrroles 5 and 6, as well as those of the parent meso-octamethylcalix[4]pyrrole (1), were investigated in acetone using 1H NMR spectroscopic and isothermal titration calorimetry (ITC) techniques and, within the error limits of the methods, were generally found to give concordant results. On the basis of the results of the ITC studies carried out in 1,2-dichloroethane, increasing the number of Tetrathiafulvalene units annulated to the calix[4]pyrrole system serves to ...
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Pyrrolo‐Tetrathiafulvalenes and Their Applications in Molecular and Supramolecular Chemistry
European Journal of Organic Chemistry, 2003Co-Authors: Jan O. Jeppesen, Jan BecherAbstract:Although Tetrathiafulvalene and its derivatives have been extensively studied as π-electron donors in the fields of molecular organic metals and electrically conducting materials for more than 30 years, the intriguing potential of Tetrathiafulvalene as a building block in molecular and supramolecular chemistry has only recently been developed. Progress in synthetic Tetrathiafulvalene chemistry has enabled the preparation of elaborate molecular architectures and, in recent years, Tetrathiafulvalene has been incorporated into a number of molecular and supramolecular systems. In this microreview we describe the background to our interest in the development of the parent pyrrolo-Tetrathiafulvalenes, followed by a journey through their applications in macrocyclic, molecular, and supramolecular chemistry. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
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A pyrrolo-Tetrathiafulvalene cage: synthesis and X-ray crystal structure.
Organic letters, 2002Co-Authors: Kent A. Nielsen, Eric Levillain, Jan O. Jeppesen, Niels Thorup, Jan BecherAbstract:[reaction: see text] A novel type of Tetrathiafulvalene-cage 4 containing three monopyrrolo-Tetrathiafulvalene units has been prepared employing a general and efficient synthetic approach. X-ray crystal structure analysis revealed that the cage is able to accommodate solvent molecules within a cavity in the solid state.
Marc Fourmigué - One of the best experts on this subject based on the ideXlab platform.
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Halogen Bonding Interactions in DDQ Charge Transfer Salts with Iodinated TTFs
Crystals, 2012Co-Authors: Julien Lieffrig, Olivier Jeannin, Kyung-soon Shin, Pascale Auban-senzier, Marc FourmiguéAbstract:Oxidation of 3,4-ethylenedithio-3'-iodo-Tetrathiafulvalene (EDT-TTF-I) and 3,4-ethylenedithio-3',4'-diiodo-Tetrathiafulvalene (EDT-TTF-I2) with DDQ afforded two different salts formulated as (EDT-TTF-I)(DDQ) and (EDT-TTF-I2)2(DDQ)*(CH3CN), both characterized with a full charge transfer to the DDQ acceptor moiety and by short and linear halogen bonding interactions between the iodine atom as halogen bond donor, and the carbonyl oxygen or the nitrile nitrogen atoms of reduced DDQ.
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Helical organization of chiral binaphthyl Tetrathiafulvalene primary amides through hydrogen bonding interactions
CrystEngComm, 2010Co-Authors: Ali Saad, Olivier Jeannin, Marc FourmiguéAbstract:Chiral Tetrathiafulvalenes, (R) or (S), or racemic, (R,S), are obtained from a phosphite-mediated cross coupling reaction of a 1,3-dithiole-2-thione derivative bearing one binaphthol moiety, and are transformed into binaphthol-based Tetrathiafulvalene ortho-diamides. The X-ray crystal structures of five intermediate chiral 1,3-dithiole-2-one and 1,3-dithiole-2-thione derivatives reveal the formation of helical structures through p-p interactions. The binaphthol-based Tetrathiafulvalene ortho-diamides, as THF or DMSO solvates, adopt different solid-state organisations, characterised either by short intramolecular hydrogen bonds or with solely intermolecular hydrogen bonds and chiral solid-state structures with short intermolecular S/S contacts.
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Tetrathiafulvalene based group xv ligands synthesis coordination chemistry and radical cation salts
Coordination Chemistry Reviews, 2009Co-Authors: Dominique Lorcy, Marc Fourmigué, Nathalie Bellec, Narcis AvarvariAbstract:This review deals with the synthesis, properties and applications of metal complexes of Tetrathiafulvalene-based group XV (N, P, As, Sb) ligands. The different synthetic methods for the preparations of Tetrathiafulvalenes (TTFs) incorporating coordination functions such as N atoms (essentially sp2 N atoms in pyridines, pyrazines, bipyridines, imines, etc.) and P atoms (essentially in tertiary phosphines) are reviewed, together with the redox properties of these free ligands, showing in most cases that the electron donating ability of the TTF core is only scarcely affected upon association with the coordinating group. Metal complexes of such ligands have been reported with a large variety of metal centers, from group 6 (Cr, Mo, W) to group 12 (Zn, Cd, Hg). Their structural and electronic and magnetic properties are described, with an emphasis on the evolution of the properties of the ligand (redox potentials, 31P NMR chemical shifts) upon coordination. Two applications of these complexes are further discussed, elaboration of multi-functional conducting materials upon TTF oxidation, redox modulation of the reactivity of the metal complex used as catalyst.
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Redox bifunctionality in a Pt(ii) dithiolene complex of a Tetrathiafulvalene diphosphine ligand.
Dalton transactions (Cambridge England : 2003), 2008Co-Authors: Kyong-soon Shin, Marc Fourmigué, Younjung Jung, Su-kyung Lee, Frédéric Barrière, Jean-françois Bergamini, Dong-youn NohAbstract:The Pt(II) dithiolene complex of a Tetrathiafulvalene diphosphine ligand exhibits two reversible redox systems at close potentials, localized on the weakly interacting TTF (Tetrathiafulvalene) and Pt(dmit) moieties.
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Halogen bonding, hydrogen bonding and fluorine segregation in conducting salts of novel halogenated Tetrathiafulvalenes
Synthetic Metals, 2002Co-Authors: Marc Fourmigué, Olivier Dautel, Thomas Devic, Benoit DomercqAbstract:Two different intermolecular interactions are described and analyzed in cation radical salts of functionalized Tetrathiafulvalenes. On the one hand, the electrostatic nature of the CNHal interaction is demonstrated through the observed structural modifications, (i) when halogenated TTFs such as I-EDT-TTF and I2-EDT-TTF are engaged with cyano anions where a strengthening of the interaction is noted, or (ii) when EDT-TTF-CN is engaged with halogenated anions where the CNHal interaction is totally suppressed. On the other hand, we took advantage of the absence of interactions experienced by aliphatic fluorinated molecules to investigate the structural and electronic properties of fluorinated Tetrathiafulvalenes such as the bis(difluoropropylenedithio)Tetrathiafulvalene. Its synthesis, electrochemical and structural properties will be described as well as different salts with linear (ICl2−) and complex (Mo6Cl142−) anions. Fluorine–fluorine segregation effects combined with C–HHal hydrogen bonds lead to striking layered structures with fluorinated bilayers while an organic–inorganic segregation is also retained with the conducting 4:1 salt of the unsymmetrically substituted (difluoropropylenedithio)Tetrathiafulvalene with Mo6Cl142−.
Daoben Zhu - One of the best experts on this subject based on the ideXlab platform.
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A new saccharide sensor based on a Tetrathiafulvalene-anthracene dyad with a boronic acid group.
The Journal of organic chemistry, 2005Co-Authors: Zhuo Wang, Deqing Zhang, Daoben ZhuAbstract:A new saccharide sensor based on a Tetrathiafulvalene−anthracene dyad with a boronic acid group was designed and synthesized. Our study employed the Tetrathiafulvalene (TTF) unit as the electron-ri...
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Novel silver(I) complexes derived from tetrakis(methylthio)Tetrathiafulvalene and bis(ethylenedithio)Tetrathiafulvalene with 3D and 1D structures
New Journal of Chemistry, 2002Co-Authors: Chunyang Jia, Cai-ming Liu, Huaiming Hu, Deqing Zhang, Wei Xu, Daoben ZhuAbstract:Novel silver(I) complexes 1 and 2 derived from tetrakis(methylthio)Tetrathiafulvalene (TMTTTF) and bis(ethylenedithio)Tetrathiafulvalene (BEDT-TTF), respectively, were prepared by the self-assembly approach. Their crystal structures were determined. Complex 1 shows a three-dimensional structure with an unprecedented 4.16-net porous inorganic layer of silver nitrate. In complex 2, silver(I) is coordinated to the BEDT-TTF+ cation and an extended 1D "zig-zag" chain is formed. The electrical conducting properties of complex 1 (after oxidation by iodine) and complex 2 were investigated.
