Two new chemosensors that exhibit high affinity and selectivity for Hg2+ in aqueous environment which operate through two different channels, optic/redox optic/fluorescent, are reported. The optical change sensing can be used even a "naked-eye" detection of ions, whereas the fluorescent response modulated by varying solvent polarity.

Doped and wired: The organization of the π functional units in amide-functionalized tetrathiafulvalene a gel by hydrogen-bonding interactions has given rise to nanofibers. Doping with iodine generates conducting material, which upon annealing gives nanowires metal-like conductivity (see current-sensing AFM image). Supporting information for this article is available on WWW under http://www.wiley-vch.de/contents/jc_2002/2007/z602483_s.pdf or from author. Please note: publisher not responsible...

Metal chelation is considered a rational therapeutic approach for interdicting Alzheimer's amyloid pathogenesis. At present, enhancing the targeting and efficacy of metal-ion chelating agents through ligand design main strategy in development next generation metal chelators. Inspired by traditional dye Thioflavin-T, we have designed new multifunctional molecules that contain both binding properties. In silico techniques enabled us to identify commercial compounds enclose molecular framework...

We report experimental evidence indicating that the nature of interaction established between HAT(CN)6, a well-known strong electron acceptor aromatic compound, with mono- or polyatomic anions switches from almost exclusive formation reversible anion−π complexes, featuring markedly charge transfer (CT) formal electron-transfer (ET) character, to quantitative and irreversible net production anion radical [HAT(CN)6]•– dianion [HAT(CN)6]2– species. The preferred mode is dictated by donor...

Radical anions 1−•−5−•, showing different lengths and incorporating up to five p-phenylenevinylene (PPV) bridges between two polychlorinated triphenylmethyl units, have been prepared by chemical or electrochemical reductions from the corresponding diradicals 1−5 which were using Wittig−Horner-type chemistry. Such radical enabled us study, means of UV−vis−NIR variable-temperature electron spin resonance spectroscopies, long-range intramolecular transfer (IET) phenomena in their ground states,...

Simultaneously being a nonradiative and noninvasive technique makes magnetic resonance imaging (MRI) one of the highly required approaches for early diagnosis follow-up tumors, specifically brain cancer. Paramagnetic gadolinium (Gd)-based contrast agents (CAs) are most widely used ones in MRI acquisitions with special interest when assessing blood–brain barrier (BBB) integrity, characteristic high-grade tumors. However, alternatives to Gd-based overcome their established toxicity. Organic...

Radical bridge design: The diquinone-tetrathiafulvalene (TTF) species shown exhibits effective electron coupling between the quinone centers which is mediated by TTF bridge. Stepwise one-electron reduction of molecule occurs, and observed potential difference events an indication that second unit affected radical already formed on other side

Novel fused donor-acceptor dyad (TTF-Q or D-A) and acceptor-donor-acceptor triad (Q-TTF-Q A-D-A) incorporating the donor tetrathiafulvalene (TTF) 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. presence reversible oxidation reduction waves for moieties was shown by cyclic voltammetry, in agreement with ratio...

The synthesis, optical and electrochemical properties, X-ray characterization of two thiazole derivatives capped by ferrocenyl groups (5 7) their model compounds with one ferrocenyl, either at 2 or 5 position the mono- bis-thiazolyl rings (3, 9, 11, 14), are presented. Bisferrocenyl forms mixed-valence species 5*+ partial oxidation which, interestingly, shows an intramolecular electron-transfer phenomenon. Moreover, reported heteroaromatic show selective ion-sensing properties. Thus,...

Functionalized gold nanoparticles with complementary H-bonding groups can control the secondary structure of xerogel fibers formed by a molecular conductor thanks to their incorporation into nanowires, which show metal-like conductivity once doped without need for annealing. The picture shows photograph xerogel, TEM images Au particles in gel and single fiber, an AFM image revealing texture gel.

An extensive investigation of aggregation phenomena occurring in solution for a family electron donor-acceptor derivatives, based on polychlorotriphenylmethyl radicals (PTM) linked via vinylene-bridge to tetrathiafulvalene (TTF) units, is presented. A large set temperature and/or concentration dependent optical absorption and spin resonance (ESR) spectra dyads bearing different number electrons with hydrogenated PTM residue offer reliable information the formation homo dimers mixed valence...

The multifunctional character and stability of PTM radicals makes them appealing in a broad range fields, from active components molecular optoelectronics to agents bio-applications.

Intramolecular electron-transfer phenomena in the radical anions derived from partial reduction of diradicals (E,E)-p-divinylbenzene-beta,beta'-ylene bis(4-tetradecachlorotriphenylmethyl) diradical (1) and (E,E)-m-divinylbenzene-beta,beta'-ylene (2) have been studied by optical ESR spectroscopy. The synthetic methodology used allows for complete control geometry 1 2, which para meta topologies, respectively, as well their E/Z isomerism. This fact is to show influence different topologies on...

Spiroannelated methanofullerenes bearing quinone-type addends including TCNQ and DCNQI analogues (3a−c, 6a,b, 8, 10, 11) have been prepared, their structural electronic properties characterized by both experimental techniques quantum-chemical calculations. The spiro[2,5-cyclohexadienone-4,61'-methanofullerene] derivatives (3a−c), the spiro[10-anthrone-9,61'-methanofullerene] (8), TCNQ- DCNQI-type (10 were isolated as [6,6] adducts. spiro[cyclohexanone-4,61'-methanofullerene] (6) was however...

A new series of donor−acceptor fused dyads consisting a C60 doubly tethered to substituted TTF moiety has been synthesized. Cyclic voltammetry the fullerene derivatives in solution shows modulation difference between first reduction potential and oxidation with substituents addend. Along neutral bichromophoric compounds, we also report generation characterization by EPR absorption spectroscopies corresponding persistent open-shell species obtained electrochemically, namely their radical...

Two new polychlorotriphenylmethyl (PTM) derivatives bearing a thioacetate and disulfide group have been synthesized to anchor on gold substrate. On the basis of these molecules, three strategies were followed prepare self-assembled monolayers (SAMs) electroactive PTMs. The resulting SAMs fully characterized by contact angle, atomic force microscopy (AFM), time-of-flight secondary ion mass spectroscopy (ToF-SIMS). high coverage surface stability demonstrated cyclic voltammetry. In addition,...

Five novel generations of phosphorus dendrimers based on a cyclotriphosphazene core with stable TEMPO radicals end groups have been synthesized and studied by EPR, SQUID, 1H NMR, 31P FT-IR, UV–vis spectroscopy. The nitroxyl exhibit strong exchange interaction, which depends the dendrimer generation temperature. An |Δms| = 2 transition has observed in each dilution conditions demonstrating intramolecular origin interaction. There exists direct proportionality between EPR intensity number...

Investigation of the transmission magnetic interactions through hydrogen bonds has been carried out for two different benzoic acid derivatives which bear either a tert-butyl nitroxide (NOA) or poly(chloro)triphenylmethyl (PTMA) radical moiety. In solid state, both acids formed dimer aggregates by complementary association carboxylic groups though bonding. This ensured that atoms with most spin density are separated from one another more than 15 A. Thus, no competing through-space exchange...

Isotropic ESR spectra have been determined for the following α-nitronyl aminoxyl radicals showing different substituents at 2-position of imidazolyl ring: 1H (1); 2H (2); 3',5'-(t-C4H9)2-4'-(HO)C6H2 (3); 4'-HOC6H4 (4); 3',5'-(HO)2C6H3 (5); 3'-HOC6H4 (6); 3',4'-(HO)2C6H3 (7); C6H5 (8); 4'-NO2C6H4 (9); 2'-HOC6H4 (10); 2',4'-(HO)2C6H3 (11); and 2'-ClC6H4 (12). Solvent dependence in a large variety solvents isotropic hyperfine coupling constants (hfcc's) 1, 4, 6, 8, 9, 10, 12 has studied first...

Abstract The gold and nickel bisdithiolene complexes based on new highly extended ligands incorporating fused tetrathiafulvalene thiophene moieties (α‐tdt=thiophenetetrathiafulvalenedithiolate dtdt=dihydro‐ thiophenetetrathiafulvalenedithiolate), were prepared characterised by using cyclic voltammetry, single crystal X‐ray diffraction, EPR, magnetic susceptibility electrical transport measurements. These complexes, initially obtained under anaerobic conditions as diamagnetic monoanic [ n Bu...

A radical switch: Covalent and noncovalent interactions have been used to functionalize silicon oxide surfaces with polychlorotriphenylmethyl radicals, which are electroactive can be reversibly reduced or oxidized nonmagnetic nonfluorescent species. Thus, the self-assembled monolayers behave as chemical switches that combine electronic absorption, fluorescence emission (see picture), magnetic outputs. Supporting information for this article is available on WWW under...

Dotierte Drähte: Die Organisation der π-Einheiten von amidfunktionalisiertem Tetrathiafulvalen in einem Gel durch Wasserstoffbrücken führt zur Bildung Nanofasern. Dotieren mit Iod erzeugt ein leitfähiges Material, das Tempern Nanodrähte metallartiger Leitfähigkeit übergeht (siehe Rasterkraftmikroskopiebild). Supporting information for this article is available on the WWW under http://www.wiley-vch.de/contents/jc_2001/2007/z602483_s.pdf or from author. Please note: The publisher not...

The poly(isocyanide) skeleton is shown to be a good support for assemblies of molecular units which permit p-type charge transport. A containing tetrathiafulvalene (TTF) moieties in the side chains has been synthesized and characterized its neutral state oxidized generate mixed valence states display mobility solution. UV−vis−NIR, EPR, Raman spectroscopies were used study electronic properties polymer doped states, generated chemically with different oxidants. broad charge-transfer band at...

An organic switch: open-shell dyad, consisting of an electron acceptor perchlorotriphenylmethyl radical unit linked to π-donor tetrathiafulvalene through a vinylene π-bridge, was synthesized (see picture). The self-assembly the dyad in solution induced by its intramolecular transfer studied.