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1.
Tetrathiafulvalene (TTF) as the prototypical electron donor for solid-state (electronics) applications is converted to the unusual cation-radical salt, TTF+* CB- (where CB- is the non-coordinating closo-dodecamethylcarboranate), for crystallographic and spectral analyses. Near-IR studies establish the spontaneous self-association of TTF+* to form the diamagnetic [TTF+,TTF+] dication and to also undergo the equally rapid cross-association with its parent donor to form the mixed-valence [TTF+*,TTF] cation-radical. The latter, most importantly, represents the first (dyad) member of a series of p-doped tetrathiafulvalene (stacked) arrays, and the thorough scrutiny of its electronic structure with the aid of Mulliken-Hush (two-state) analysis of the diagnostic (intervalence) NIR band reveals Robin-Day Class II behavior. The theoretical consequences of the unique structure of the mixed-valence [TTF+*,TTF] dyad on (a) the electron-transfer mechanism for self-exchange, (b) the molecular-orbital analysis of the Marcus reorganization energy, and (c) the ab initio computation of the coupling element or transfer integral in p-doped (solid-state) arrays are discussed. 相似文献
2.
Leroy-Lhez S Baffreau J Perrin L Levillain E Allain M Blesa MJ Hudhomme P 《The Journal of organic chemistry》2005,70(16):6313-6320
A donor-acceptor dyad system involving tetrathiafulvalene (TTF) as donor attached by a flexible spacer to perylene-3,4:9,10-bis(dicarboximide) (PDI) as acceptor was synthesized and characterized. The strategy used the preliminary synthesis of an unsymmetrical PDI unit bearing an alcohol functionality as anchor group. Single-crystal analysis revealed a highly organized arrangement in which all PDI molecules are packed in a noncentrosymmetrical pattern. It was shown that the fluorescence emission intensity of the TTF-PDI dyad can be reversibly tuned depending on the oxidation states of the TTF unit. This behavior is attributed to peculiar properties of TTF linked to a PDI acceptor, which fluoresces intrinsically. Consequently, this dyad can be considered as a new reversible fluorescence-redox dependent molecular system. 相似文献
3.
Design and Synthesis of Aviram–Ratner‐Type Dyads and Rectification Studies in Langmuir–Blodgett (LB) Films
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Dr. Govindasamy Jayamurugan Dr. Vijayendran Gowri David Hernández Prof. Dr. Santiago Martin Dr. Alejandro González‐Orive Dr. Cagatay Dengiz Dr. Oliver Dumele Prof. Dr. Francesc Pérez‐Murano Dr. Jean‐Paul Gisselbrecht Prof. Dr. Corinne Boudon Dr. W. Bernd Schweizer Dr. Benjamin Breiten Dr. Aaron D. Finke Prof. Dr. Gunnar Jeschke Dr. Bruno Bernet Prof. Dr. Laurent Ruhlmann Prof. Dr. Pilar Cea Prof. Dr. François Diederich 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(30):10539-10547
The design and synthesis of Aviram–Ratner‐type molecular rectifiers, featuring an anilino‐substituted extended tetracyanoquinodimethane (exTCNQ) acceptor, covalently linked by the σ‐spacer bicyclo[2.2.2]octane (BCO) to a tetrathiafulvalene (TTF) donor moiety, are described. The rigid BCO spacer keeps the TTF donor and exTCNQ acceptor moieties apart, as demonstrated by X‐ray analysis. The photophysical properties of the TTF‐BCO‐exTCNQ dyads were investigated by UV/Vis and EPR spectroscopy, electrochemical studies, and theoretical calculations. Langmuir–Blodgett films were prepared and used in the fabrication and electrical studies of junction devices. One dyad showed the asymmetric current–voltage (I–V) curve characteristic for rectification, unlike control compounds containing the TTF unit but not the exTCNQ moiety or comprising the exTCNQ acceptor moiety but lacking the donor TTF part, which both gave symmetric I–V curves. The direction of the observed rectification indicated that the preferred electron current flows from the exTCNQ acceptor to the TTF donor. 相似文献
4.
Self‐Assembled Architectures with Segregated Donor and Acceptor Units of a Dyad Based on a Monopyrrolo‐Annulated TTF–PTM Radical
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Manuel Souto Dr. Marta V. Solano Morten Jensen Dan Bendixen Francesca Delchiaro Prof. Alberto Girlando Prof. Anna Painelli Prof. Jan O. Jeppesen Prof. Concepció Rovira Dr. Imma Ratera Prof. Jaume Veciana 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(24):8816-8825
An electron donor–acceptor dyad based on a polychlorotriphenylmethyl (PTM) radical subunit linked to a tetrathiafulvalene (TTF) unit through a π‐conjugated N‐phenyl–pyrrole–vinylene bridge has been synthesized and characterized. The intramolecular electron transfer process and magnetic properties of the radical dyad have been evaluated by cyclic voltammetry, UV/Vis spectroscopy, vibrational spectroscopy, and ESR spectroscopy in solution and in the solid state. The self‐assembling abilities of the radical dyad and of its protonated non‐radical analogue have been investigated by X‐ray crystallographic analysis, which revealed that the radical dyad produced a supramolecular architecture with segregated donor and acceptor units in which the TTF subunits were arranged in 1D herringbone‐type stacks. Analysis of the X‐ray data at different temperatures suggests that the two inequivalent molecules that form the asymmetric unit of the crystal of the radical dyad evolve into an opposite degree of electronic delocalization as the temperature decreases. 相似文献
5.
利用Wittig反应将高荧光量子产率的蒽基团通过双键连接在四硫富瓦烯单元上,合成了二元共轭体系化合物TTFan.在氧化作用的控制下,四硫富瓦烯单元的给电子能力降低,TTFan的荧光发射强度增大至原来的十几倍,实现了荧光的“off-on”过程. 相似文献
6.
New versatile building block for the construction of tetrathiafulvalene-based donor-acceptor systems
[reaction: see text] A new dissymmetrical tetrathiafulvalene (TTF) derivative 1 was synthesized as a versatile building block to reach TTF-based donor-acceptor assemblies incorporating C(60) in triad C(60)-TTF-C(60) 2 and/or p-benzoquinone (Q) in fused dyad Q-TTF 3 and triad Q-TTF-C(60) 4. 相似文献
7.
Zhang G Zhang D Zhao X Ai X Zhang J Zhu D 《Chemistry (Weinheim an der Bergstrasse, Germany)》2006,12(4):1067-1073
Due to the unique features of the tetrathiafulvalene (TTF) unit, such as the electron-donating ability and presence of methylthio groups, dyad 1 can be assembled on the surfaces of gold nanoparticles, as indicated by absorption, electrochemical, and fluorescent-spectral studies. Dyad 1 can also be disassembled by the addition of thiols. Assembly of dyad 1 on the surfaces of gold nanoparticles leads to the formation of a triad (A1-D-A2), which in turn modulates the photoinduced electron-transfer process within dyad 1. Accordingly, the fluorescence intensity of dyad 1, after assembly with gold nanoparticles, increases, and the fluorescence lifetime is prolonged. Furthermore, the assembly of dyad 1 on gold nanoparticles facilitates photodimerization of the anthracene units of dyad 1. Both fluorescence and photodimerization are associated with the excited-state behavior of the anthracene unit, thus it may be concluded that the excited-state properties of the anthracene unit can be tuned upon complexation with gold nanoparticles. 相似文献
8.
[reaction: see text] 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-rich group in the saccharide sensor instead of an amine group, and this new sensor detects fructose with good selectivity. 相似文献
9.
A TTF-linked porphyrin dyad and its zinc complex have been synthesized as novel photosystems with a redox-active pendant. The two chromophores of these dyads are not interactive in the absorption spectra, but the fluorescence of the porphyrin chromophore is dramatically quenched by intramolecular electron transfer from the TTF pendant. 相似文献
10.
Dumur F Gautier N Gallego-Planas N Sahin Y Levillain E Mercier N Hudhomme P Masino M Girlando A Lloveras V Vidal-Gancedo J Veciana J Rovira C 《The Journal of organic chemistry》2004,69(6):2164-2177
Novel fused donor-acceptor dyad (TTF-Q or D-A) and acceptor-donor-acceptor triad (Q-TTF-Q or A-D-A) incorporating the donor tetrathiafulvalene (TTF) and the acceptor p-benzoquinone (Q) have been synthesized. The solution UV-vis spectra of these molecules display a low-energy absorption band that is attributed to an intramolecular charge transfer between both antagonistic units. The presence of reversible oxidation and reduction waves for the donor and acceptor moieties was shown by cyclic voltammetry, in agreement with the ratio TTF/quinone(s) units. The successive generation from these compounds of the cation radical and anion radical obtained upon (electro)chemical oxidation and reduction, respectively, was monitored by optical and ESR spectroscopies. The anion radical Q-TTF-Q(-.) triad was demonstrated to be a class II mixed-valence system with the existence of a temperature-dependent intramolecular electron transfer. The crystallographic tendency of these fused systems to overlap in mixed stacks of alternating A-D-A units is also discussed. 相似文献
11.
Dr. Hongpeng Jia Belinda Schmid Dr. Shi‐Xia Liu Michael Jaggi Philippe Monbaron Dr. Sheshanath V. Bhosale Shadi Rivadehi Prof. Steven J. Langford Dr. Lionel Sanguinet Dr. Eric Levillain Dr. Mohamed E. El‐Khouly Prof. Ysushi Morita Prof. Shunichi Fukuzumi Prof. Silvio Decurtins 《Chemphyschem》2012,13(14):3370-3382
A tetrathiafulvalene (TTF) donor is annulated to porphyrins (P) via quinoxaline linkers to form novel symmetric P–TTF–P triads 1 a – c and asymmetric P–TTF dyads 2 a , b in good yields. These planar and extended π‐conjugated molecules absorb light over a wide region of the UV/Vis spectrum as a result of additional charge‐transfer excitations within the donor–acceptor assemblies. Quantum‐chemical calculations elucidate the nature of the electronically excited states. The compounds are electrochemically amphoteric and primarily exhibit low oxidation potentials. Cyclic voltammetric and spectroelectrochemical studies allow differentiation between the TTF and porphyrin sites with respect to the multiple redox processes occurring within these molecular assemblies. Transient absorption measurements give insight into the excited‐state events and deliver corresponding kinetic data. Femtosecond transient absorption spectra in benzonitrile may suggest the occurrence of fast charge separation from TTF to porphyrin in dyads 2 a , b but not in triads 1 a – c . Clear evidence for a photoinduced and relatively long lived charge‐separated state (385 ps lifetime) is obtained for a supramolecular coordination compound built from the ZnP–TTF dyad and a pyridine‐functionalized C60 acceptor unit. This specific excited state results in a (ZnP–TTF)?+ ??? (C60py)?? state. The binding constant of ZnII ??? py is evaluated by constructing a Benesi–Hildebrand plot based on fluorescence data. This plot yields a binding constant K of 7.20×104 M ?1, which is remarkably high for bonding of pyridine to ZnP. 相似文献
12.
The metal ion-promoted electron transfer occurs to all new dyads 1, 2, 3, and 4, even one of them, dyad 4, which has a rather weak electron acceptor unit. The results also indicate that the metal ion-promoted electron transfer within the dyads is influenced by the electron accepting abilities of quinone units; dyad 2 with the strongest electron acceptor among the four dyads shows the strongest absorption and ESR signals attributed to TTF.+ in the presence of metal ions. 相似文献
13.
Guldi DM Gonzalez S Martin N Anton A Garin J Orduna J 《The Journal of organic chemistry》2000,65(7):1978-1983
Triazoline[4,5][60]fullerenes are strong electron acceptors that form with tetrathiafulvalene (TTF), a novel type of donor-acceptor dyad exhibiting efficient improved electron-transfer dynamics. In particular, a rapid photoinduced intramolecular electron transfer, forming a charge-separated state, is followed by a slow charge recombination to generate the fullerene triplet excited state in moderate quantum yields. 相似文献
14.
Saha S Flood AH Stoddart JF Impellizzeri S Silvi S Venturi M Credi A 《Journal of the American Chemical Society》2007,129(40):12159-12171
A multicomponent [2]rotaxane designed to operate as a molecular shuttle driven by light energy has been constructed, and its properties have been investigated. The system is composed of (1) a light-fueled power station, capable of using the photon energy to create a charge-separated state, and (2) a mechanical switch, capable of utilizing such a photochemically generated driving force to bring about controllable molecular shuttling motions. The light-fueled power station is, in turn, a dyad comprising (i) a pi-electron-accepting fullerene (C60) component and (ii) a light-harvesting porphyrin (P) unit which acts as an electron donor in the excited state. The mechanical switch is a redox-active bistable [2]rotaxane moiety that consists of (i) a tetrathiafulvalene (TTF) unit as an efficient pi-electron-donor station, (ii) a dioxynaphthalene (DNP) unit as a second pi-electron-rich station, and (iii) a tetracationic cyclobis(paraquat-p-phenylene) (CBPQT4+) pi-electron-acceptor cyclophane, which encapsulates the better pi-electron-donating TTF station. Diethylene glycol spacers were conveniently introduced between the electroactive components in the dumbbell-shaped thread to facilitate the template-directed synthesis of the [2]rotaxane. A modular synthetic approach was undertaken for the overall synthesis of this multicomponent bistable [2]rotaxane, beginning with the syntheses of the P-C60 dyad unit and the two-station TTF-DNP-based [2]rotaxane separately, using conventional synthetic methodologies. These two components were finally stitched together by an esterification to afford the target rotaxane. Its structure was characterized by 1H NMR spectroscopy and mass spectrometry as well as by UV-vis-NIR absorption spectroscopy and voltammetry. The observations reflect remarkable electronic interactions between the various units, pointing to the existence of folded conformations in solution. The redox-driven shuttling process of the CBPQT4+ ring between the two competitive electron-rich recognition units, namely, TTF and DNP, was investigated by electrochemistry and spectroelectrochemistry as a means to verify its operational behavior prior to the photophysical studies related to light-driven operation. The oxidation process of the TTF unit is dramatically hampered in the rotaxane, thereby reducing the efficiency of the shuttling motion. These results confirm that, as the structural complexity increases, the overall function of the system no longer depends simply on its "primary" structure but also on higher-level effects which are reminiscent of the secondary and tertiary structures of biomolecules. 相似文献
15.
Bang-Tun Zhao Xiao-Min Zhu Qi-Ming Peng Zhen-Ning Yan Franck Le Derf Marc Sallé 《Central European Journal of Chemistry》2011,9(6):1102-1108
A novel redox-active calix[4]arene-TTF 5 was prepared by the reaction of p-tert-butylcalix[4]arene 4 with the tosylated TTF 3 in the presence of cesium fluoride. The structure of the dyad 5 was identified by X-ray diffraction analysis, and the preliminary electrochemical properties of 5 were investigated by cyclic voltammetry (CV), for which two reversible one-electron waves were observed. Moreover, the UV-vis
absorption spectra studies show that the dyad 5 undergoes progressive oxidation at the TTF moiety in presence of increasing amounts of Cu2+ or Hg2+.
相似文献
16.
Allard E Oswald F Donnio B Guillon D Delgado JL Langa F Deschenaux R 《Organic letters》2005,7(3):383-386
[structure: see text] [60]Fullerene was functionalized with a TTF derivative and a bis-mesogenic fragment. The synthetic methodology was based on the addition of a malonate derivative to C60 (Bingel-type reaction). Both the malonate and dyad showed smectic B and A phases. The supramolecular organization within the smectic layers was of the monolayer type for the malonate and of the bilayer type for the fullerene derivative. In the latter case, the supramolecular organization was governed by the C60 unit. 相似文献
17.
François Riobé Philippe Grosshans Dr. Helena Sidorenkova Dr. Michel Geoffroy Prof. Narcis Avarvari Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(2):380-387
Reaction of 2,4,6‐trichloro‐1,3,5‐triazine with lithiated tetrathiafulvalene (TTF) in stoichiometric conditions, followed by treatment with sodium methanolate, provides mono‐ and bis(TTF)–triazines as new covalently linked (multi)donor–acceptor systems. Single‐crystal X‐ray analyses reveal planar structures for both compounds, with formation of peculiar segregated donor and acceptor stacks for the mono(TTF)–triazine compound, while mixed TTF–triazine stacks establish in the case of the bis(TTF) derivative. Cyclic voltammetry measurements show reversible oxidation of the TTF units, at rather low potential, with no splitting of the oxidation waves in the case of the dimeric TTF, whereas irreversible reduction of the triazine core is observed. Intramolecular charge transfer is experimentally evidenced through solution electronic absorption spectroscopy. Time‐dependent DFT calculations allow the assignment of the charge transfer band to singlet transitions from the HOMO of the donor(s) to the LUMO of the acceptor. Solution EPR measurements correlated with theoretical calculations were performed in order to characterize the oxidized species. In both cases the spectra show very stable radical species and contain a triplet of doublet pattern, in agreement with the coupling of the unpaired electron with the three TTF protons. The dication of the bis(TTF)–triazine is paramagnetic, but no spin–spin exchange interaction could be detected. 相似文献
18.
Wu H Zhang D Su L Ohkubo K Zhang C Yin S Mao L Shuai Z Fukuzumi S Zhu D 《Journal of the American Chemical Society》2007,129(21):6839-6846
Intramolecular electron transfer is observed for two new substituted tetrathiafulvalene (TTF)-quinone dyads 1 and 2 in the presence of metal ions. On the basis of the electrochemical studies of reference compound 5 and the comparative studies with dyad 3, it was proposed that the synergic coordination of the radical anion of quinone and the oligoethylene glycol chain with metal ions may be responsible for stabilizing the charge-separation state and thus facilitating the electron-transfer process. Most interestingly, the intramolecular electron-transfer processes within these two dyads can be modulated by UV-vis light irradiation in the presence of spiropyran, by taking advantage of its unique properties. 相似文献
19.
《中国化学》2018,36(9):845-850
The arylthio‐substituted tetrathiafulvalenes (Ar‐S‐TTFs) are electron donors having three reversible states, neutral, cation radical, and dication. The charge‐transfer (CT) between Ar‐S‐TTFs ( TTF1 — TTF3 ) and iodine (I2) is reported herein. TTF1 — TTF3 show the CT with I2 in the CH2Cl2 solution, but they are not completely converted into cation radical state. In CT complexes of TTF1 — TTF3 with I2, the charged states of Ar‐S‐TTFs are distinct from those in solution. TTF1 is at cation radical state, and TTF2 — TTF3 are oxidized to dication. The iodine components in complexes show various structures including 1‐D chain of V‐shaped (I5)–, and 2‐D and 3‐D iodine networks composed of I2 and (I3)–. 相似文献
20.
Kaminska I Das MR Coffinier Y Niedziolka-Jonsson J Woisel P Opallo M Szunerits S Boukherroub R 《Chemical communications (Cambridge, England)》2012,48(9):1221-1223
A one step process for simultaneous reduction and functionalization of graphene oxide using tetrathiafulvalene (TTF) is described. Chemical oxidation of TTF to TTF(2+) using an aqueous solution of Fe(ClO(4))(3) expels the charged molecule from the graphene nanosheets, while subsequent immersion in neutral TTF solution allows the capture of the TTF molecules. 相似文献