Tetrathiafulvalene. VIII. Ethylenverbrückte polymere Tetrathiafulvalene

Tetrathiafulvalenes. VIII. Ethylene-bridged Polymer Tetrathiafulvalenes Syntheses and properties of ethylene-bridged polymer tetrathiafulvalenes are described. These polymers react with bromine, iodine or tetracyanoquinodimethane to form the radical cation salts, whose electrical conductivity are estimated by means of powder compactions. The polymer radical cation salts have a higher conductivity than the polymer TTF (σ_RT max. 10⁻⁵ Ω⁻¹cm⁻¹). The differences in the conductivity between polymer TTF-cationhalides and polymer TTF-TCNQ-salts are small.     

Tetrathiafulvalene. XXV [1]. Konjugativ verknüpfte polymere Tetrathiafulvalene (TTF)

Tetrathiafulvalenes. XXV. Conjugative Connected Polymeric Tetrathiafulvalenes (TTF) Syntheses and properties of a conjugative connected polymeric TTF (by tetrahydroanthracene units) and phenylene-bridged polymeric TTF are described. These polymers react with bromine, iodine or tetracyanoquinodimethane and form the radical cation salts, whose electrical conductivity is determined. The conjugatively connected polymeric radical cation salts show a higher conductivity than the twisted phenylene-bridged polymeric radical cation salts.     

Tetrathiafulvalene. XIX. Synthese und Eigenschaften elektronenleitender Poly-Dithiolenkomplexe mit Ethylentetrathiolat und Tetrathiafulvalentetrathiolat als Brückenliganden

Tetrathiafulvalenes. XIX. Synthesis and Properties of Electron Conducting Poly-Dithiolene Complexes with Ethylene Tetrathiolat and Tetrathiafulvalene Tetrathiolat as Bridge Ligands [1,3]-Dithiolo[4,5-d]-1,3-dithiol-2,5-dione 7 and 5-(5-oxo[1,3]-dithiolo[4,5–d]1,3-dithiole-2-ylidene)[1,3]-dithiolo[4,5–d]1,3–dithiol-2-one 8 were synthesised from 1,3-dithiole-2-thione-4,5-dithiolat. The ligands react with salts of iron, cobalt, nickel, palladium, platinum and copper to give the polymer complexes 22a–g and 23a–e , respectively. Irradiation of 7 in the presence of iron penta-, dicobalt octa- or nickel tetracarbonyl gives the corresponding dithiolene complexes 21a–c . The amorphous insoluble polymer complexes from types 21, 22 , and 23 have been characterised by i.r.-spectroscopy, susceptibility and conductivity measurements. The nickel complexes have the highest electrical conductivity (σ_RT ∼ 10⁻¹Ω⁻¹cm⁻¹, pellets) with a very low activation energy (0,045 eV, 100–300 K) A high electron delocalization in the direction of the polymer chain and an easy charge transfer from chain to chain is supposed.     

Tetrathiafulvalene. IX. Elektrische Leitfähigkeit phenylsubstituierter,benzo- und naphthokondensierter Tetrathiafulvalen-TCNQ-Komplexe

Tetrathiafulvalenes. IX. Electrical Conductivity of Phenylsubstituted, Benzo- and Naphthocondensed Tetrathiafulvalene-TCNQ-Complexes. Complex formation of phenylsubstituted, benzo- and naphthocondensed tetrathiafulvalenes with tetracyanoquinodimethane and iodine is described. The electrical conductivity is high in the complexes, when radical salts of donor and acceptor are formed and the donator has a planar geometry.     

Tetrathiafulvalene. XXVIII. Diastereoselektive Bildung unsymmetrisch substituierter Tetrathiafulvalene

Tetrathiafulvalenes. XXVIII. Diastereoselective Formation of Unsymmetrically Substituted Tetrathiafulvalenes As a part of our work on chemistry of tetrathiafulvalenes, we make a contribution to elucidate the mechanism of forming tetrathiafulvalenes starting from 1,3-dithiole derivatives. We describe the synthesis of unsymmetrically substituted tetrathiafulvalenes ( 8a–i ) starting with the 2H-1,3-dithiolium salt ( 7a–i )/tert. amine, 2-ethylthio-1,3-dithiolium salt ( 5a–i )/triphenylphosphine or 1,3-dithiole-2-thione ( 4a–i )/triethyl phosphite. If the 1,3-dithiole derivatives are substituted by bulky groups the isolation of the cis- and trans-isomers was possible due to differences in the solubility. In these cases ( 8c–i ) the predominant formation of the cis-isomer is observed in the reaction of 2-ethylthio-1,3-dithiolium salts ( 5c–i ) with triphenylphosphine or 1,3-dithiole-2-thiones ( 4c–i ) with triethyl phosphite. This result is in agreement with the formation of an intermediate, analogously to the Wittig reaction. In the reaction of 2H-1,3-dithiolium salts ( 7a–i ) with tertiary amines the relation of isolated cis- and trans-isomers is not 1:1 and depends on the bulkiness of the tertiary amine. These observations exclude in these three reactions a carbene mechanism for the dimerization of the 1,3-dithiole units to tetrathiafulvalenes.     

Leitfähige Polymere mit Tetrathiafulvalenstruktur

Conductive Polymers with Tetrathiafulvalene Structure Synthesis and properties of phenylene- and biphenyl-bridged polymer tetrathiafulvalenes are described. These polymers react with bromine or iodine and provide the radical-cationhalides, whose electrical conductivity as powder compactions are estimated. The conductivity depends on stoichiometric composition of the radicale-salts. The phenylene-bridged polymer-salts show a much higher conductivity than the biphenyl-bridged ones and reach values of 10⁻³ ω⁻¹ cm⁻¹. The monomer salts have a higher conductivity than the polymer salts (max. 10⁻¹ Ω⁻¹ cm⁻¹).     

Tetrathiafulvalene. XXVII [1] Darstellung und Eigenschaften cis- und trans-isomerer Dihydrophenanthreno-Tetrathiafulvalene

Tetrathiafulvalenes. XXVII. Syntheses and Properties of cis- and trans-Isomers of Dihydrophenanthreno-Tetrathiafulvalenes The synthesis of anellated tetrathiafulvalenes (TTF) 10a–c , 11a–b via the 1,3-dithiolium salt/triethylamin or 1,3-dithiole-2-thione/triethyl phosphite route is described. The dihydrophenanthreno-anellated TTFs 10a, b can be thermally transformed into the phenanthreno-anellated TTFs 11a, b . Only in the case of the dihydrophenanthreno-anellated TTF 10b (with “α-naphthyl structure”) the isolation of the cis- and trans-isomer was possible due to differences in the solubility. Starting from the pure cis- or trans-isomer the radical salts of 10b are reducible to a 1:1 mixture of the cis/trans stereo isomers. The spectroscopic, electrochemical, and conductivity properties of the synthesized TTFs and their complexes with iodine, TCNQ, and DDQ are described.     

Tetrathiafulvalene. XXI. Synthese von Tetrathiafulvalenen aus 2-Alkylthio-, 2-Arylthio- und 2-Alkylseleno-1,3-dithioliumsalzen

Tetrathiafulvalenes. XXI. Syntheses of Tetrathiafulvalenes from 2-Alkylthio-, 2-Arylthio- and 2-Alkylseleno-1,3-dithiolium Salts In the reaction of 2-alkylthio-, 2-arylthio- or 2-alkylseleno-1, 3-dithiolium salts with trivalent phosphorus compounds in acetonitril tetrathiafulvalenes 2 are formed. As an intermediate we suppose a phosphorane, which reacts with further 1,3-dithiolium salt to provide the tetrathiafulvalene. By the application of a 2-alkylthio-1,3-dithiolium salt a monomethin dye is formed in a side reaction. When the reaction is carried out in methanol, the phosphorane is trapped by the solvent and a 2H-1,3-dithiolium salt is obtained.     

Reactions of Photoexcited Triplet States of Zinc Porphyrin with Transient Radicals in Aqueous Solutions

The technique of simultaneous pulse radiolysis and photolysis, PRAP, has been utilized to study the reactions of various radicals with ground state ZnTPPS and the triplet state ZnTPPS^T in aqueous solutions. The radicals H and OH add to both states with k ∼ 1 × 10¹⁰ M⁻¹ s⁻¹. The CH₂C(CH₃)₂OH radical from t-BuOH is relatively inert toward ZnTPPS but reacts rapidly (k = 1.8 × 10⁹ M⁻¹ s⁻¹) with ZnTPPS^T to form an adduct. Electron transfer reactions are found to be about an order of magnitude faster with the triplet than with the ground state. The (CH₃)₂COH radical reduces both ZnTPPS (k = 1 × 10⁸ M⁻¹ s⁻¹) and ZnTPPS^T (k = 3 × 10⁹ M⁻¹ s⁻¹) to the anion radical (ZnTPPS)⁻. The radical Br⁻₂ oxidizes both states to the cation radical (ZnTPPS)⁺ with k = 8 × 10⁸ M⁻¹ s⁻¹ for the ground state and 5 × 10⁹ M⁻¹ s⁻¹ for the triplet. The transient cation Cd⁺ reduces both states with a diffusion-controlled rate (k = 1 × 10¹⁰ M⁻¹ s⁻¹) to produce the anion radical. The above mechanisms of radical addition and electron transfer are also supported by the product spectra.     

Tetrathiafulvalene. XXII [1] Redox- und spektroskopische Eigenschaften von Tetrathiafulvalenen (TTF) und Tetraselenafulvalenen (TSF) sowie deren Mono- und Dikationen

Tetrathiafulvalenes. XXII. Redox- and Spectroscopic Properties of Tetrathiafulvalenes (TTF) and Tetraselenafulvalenes (TSF) and their Mono- and Dications The polarographic oxidation potential of TTF is decreased by alkyl- and increased by aryl-substituents. The oxidation potentials of arylated TTF can be correlated with σ⁺-constants (σ  0,1). TSF are weaker donors than the respective TTF. Alkyl substitution at TTF causes a bathocromic shift and aryl substitution a hypsochromic shift of the longest wavelength absorption band. In the mono- and dications of TTF a bathochromic shift of this absorption band is observed by alkyl- as well as aryl-substituents which is especially pronounced, when the molecule is planar.     

Novel Topology in Semiconducting Tetrathiafulvalene Lanthanide Metal-Organic Frameworks

Tetrathiafulvalene tetrabenzoate (TTFTB) and several lanthanide ions self-assemble into metal-organic frameworks (MOFs) that exhibit a novel topology, a (3,3,3,6,6)-coordinated net, which features an unusual ligand coordination mode and stacking motif. The Yb and Lu MOFs are electrically conductive, with pellet conductivity values of 9(7) × 10⁻⁷ and 3(2) × 10⁻⁷ S/cm, respectively. The crystallographically-determined bond lengths indicate partial oxidation of the ligand, with close S ⋅ ⋅ ⋅ S contacts between ligands providing likely charge transport pathways in the material. Magnetometry reveals temperature-independent paramagnetism, consistent with the presence of ligand-based radicals, as well as weak antiferromagnetic coupling between Yb³⁺ centers. These results illustrate the diversity of MOF structures and properties that are accessible with the TTFTB ligand owing to its electroactive nature, propensity for intermolecular interactions, and conformational flexibility.     

The Effect of the Counter Anion on the Complexation of Alkali Metal Salts to Polyethylene Glycol

The complexation of alkali metal salts by polyethylene glycol is strongly dependent on the counter anion of the salt. In general, potassium salts are more easily complexed. In fact, sodium salts at low free energy of formation are barely complexed at all. By conductometric and index of refraction measurements it was shown that anions capable of hydrogen bonding such as OH⁻, F⁻, HSO⁻₄ and HCO⁻₃ were ion paired to the complexed potassium cation and existed as relatively “naked” anions. Other anions such as Cl⁻, Br⁻, I⁻, SCN⁻, NO⁻₃, NO⁻₂ AND HF⁻₂ existed as disassociated anions with significant solvation shells. The use of polyethylene glycol as a phase transfer catalyst considering the results found is discussed.     

Tetrathiafulvalene. XVI. Spektroskopische und elektrische Eigenschaften von TTF und TTF-TCNQ-Komplexen

Tetrathiafulvalenes. XVI. Spectroscopic and Electrical Properties of TTF and TTF-TCNQ-Complexes UV-vis-spectra of mono- and dications of the TTF 2 show in comparison to those of TTF 1 and 3 that the aryl substituent in the TTF 2 is more twisted from the TTF-plane than in 1 and 3 . Absorption maxima of mono- and dications from TTF 1 and 3 lie at a significantly greater wavelength than absorption maxima of mono- and dications from TTF 2 , because a better electronic interaction between substituents in the aryl-group and the positively charged dithiolium-ring is possible. TCNQ-complexes of smoother TTF 3 also have a higher electrical conductivity than TCNQ-complexes of 2 .     

The effect of pyridine ring functionalization on the conductivity of crosslinked CO-poly(styrene-4-vinylpyridine) derivatives

The effect of pyridine ring functionalization in crosslinked co-poly(styrene-4-vinylpyridine) on electrochemical behavior was studied using impedance spectroscopy. The introduction of a substituent on the nitrogen atom increases conductivity from 10^-14 to around 10^-11 Scm^-1 at room temperature, but the effect of the substituent becomes more evident at 64°C, at which the n-butyl derivative (co-poly[styrene-[4-vinyl(N-butylpyridinium bromide)]])-(3) has a higher conductivity (ω = 7 × 10⁻¹⁰ Scm⁻¹) than the hydrogen analog (co-poly[styrene-[4-vinyl(pyridinium bromide)]])-(2) (ω = 4.3 × 10⁻¹⁰ Scm⁻¹), while the iodo derivative (co-poly[styrene-[4-vinyl(N-iodopyridinium bromide)]])-(6) has a conductivity ten times lower. Further increase in the conductivity was observed upon the substitution of the bromine anion with the three-bromide anion (Br₃)⁻, but the effect depends on the substituent on the nitrogen atom: 4.4 times higher conductivity was found for the hydrogen pyridinium salt (4) in comparison with sample (2), and the conductivity increases 30-fold for the N-butyl derivative (5) compared with sample (3). The conductivity increased exponentially with temperature and the activation energy values vary from 0.76 to 1.01 eV. Impedance responses for dried samples of pyridinium salts (2), (3), (4), (5), and (6) suggested electron-type conductivity. The conductivity of crosslinked polymers depends very much on the conditions, and increases by several orders of magnitude when water or methanol is present in the atmosphere during measurement. The conductivity also depends on the structure of the substituent attached to the nitrogen atom: ω = 5 × 10⁻⁴ Scm⁻¹ and ω = 2 × 10⁻⁴ Scm⁻¹ for hydrogen bromide (2) and N-butyl bromide derivative (3), but the conductivity of the N-iodo derivative (6) changed very little. In contrast, the impedance responses for samples stored in the presence of water or methanol suggested ion conductivity. © 1996 John Wiley & Sons, Inc.     

Zur Rolle von EDA-Komplexen bei kationischen Polymerisationen. VI[1]. Wechselwirkung von Halogenidionen mit organischen aπ-Elektronenacceptoren

The Role of Donor-Acceptor Complexes in Cationic Polymerisations. The Interaction of Halide Ions with Organic aπ-Acceptors The anions of salts of the type Kat⁺X⁻ (Kat⁺  Li⁺, Na⁺, Et₄N⁺; X⁻  Cl⁻, Br⁻, I⁻) form donor-acceptor complexes with organic a π-acceptors. The long-wave charge-transfer absorption show a bathochrome shift with higher periodic numbers of X⁻ and increasing electron affinity of the acceptors Acc. Strong acceptors form radical ions very rapidly with X  I and slowly with X  Br. Cl. The interactions in the system Kat⁺X⁻ → Acc are influenced by solvents in a very complex way. As acceptors they interact preferably with the halide ion X⁻ and, hence, reduce its donicity for the competing acceptor Acc. As donors they change the dissociation of the ion pair Kat⁺X⁻ by solvation of the cation Kat⁺ and influence in that indirect way also the donicity of X⁻ for the acceptor Acc.     

Chemical copolymerization of aniline with o‐chloroaniline: thermal stability by spectral studies

Poly(aniline‐co‐o‐chloroaniline) salts were synthesized by chemical copolymerization of aniline with o‐chloroaniline using three different acids. The polymer salt samples were heat treated at four different temperatures (150, 200, 275 and 375 °C) and the thermal stability of the polymer salts were studied by conductivity, electron paramagnetic resonance (EPR), infrared (IR) and electronic absorption spectral measurements. The conductivity of the copolymers could be controlled in a broad range from 10 S cm⁻¹ for homopolymer of aniline to 10⁻⁴ S cm⁻¹ for those of o‐chloroaniline. No structural changes took place up to 200 °C and this was confirmed from EPR, IR and electronic absorption spectra. No definite correlation exists between conductivity and spin concentration. © 2000 Society of Chemical Industry     

Synergistic effect of cation ordered structure and grain boundary engineering on long-term cycling of Li0.35La0.55TiO3-based solid batteries

In this study, Li_0.35La_0.55TiO₃ (LLTO) was coupled with Al-doped lithium lanthanum zirconate (LLZO) to improve the grain boundary and total conductivity. The obtained ceramic pellets (LLTZO) demonstrated a recordable grain boundary and total conductivity of 3.41 × 10⁻⁴ and 3.03 × 10⁻⁴ S/cm, respectively. The obtained results establish that the heteroatoms can perturb the cation ordered structure and improve the 3D conductivity in grain bulk. In addition, the residual Al-doped LLZO on the grain boundary led to a decline in the boundary resistance. An LiFeCoPO₄ |Li cell was adopted to demonstrate the enhanced conductivity of LLTO. The solid state battery rendered a specific capacity of over 101.2 mAhg⁻¹ after 300 cycles at a relatively high rate of 0.5C. It is established from the experiments that manufacturing a solid battery using the all-coating technique provides a promising approach to achieve a practical application.     

Enhanced ion conductivity of poly(ethylene oxide)-based single ion conductors with lithium 1,2,3-triazolate end groups

Poly(ethylene oxide) (PEO)-based single ion conductors (SICs) are of great interest for applications in modern lithium ion batteries. They have several advantages over other common electrolytes such as high cation transference numbers, low toxicity, and nonflammability, but their major disadvantage is the low ion conductivity. Here, linear PEO-based SICs with lithium 1,2,3-triazolate (TrLi) end groups are synthesized and studied in terms of crystallinity by differential scanning calorimetry, and with respect to ion conductivity by impedance spectroscopy. Introduction of TrLi end groups to PEO chains reduces its crystallinity and melting temperature as well as an enhancement of the ion conductivity up to 8.0·10⁻⁶ S cm⁻¹ at 70°C is observed. The increased ion conductivity is a direct result of the Tr rings, which can actively contribute to the conduction mechanism. In comparison with conductivities of other PEO-based SICs reached so far (σ₀ ≤ 10⁻⁶ S cm⁻¹), the results of this study show that the introduction of TrLi end groups is a new approach to enhance the Li⁺-ion conductivity of PEO-based SICs that have also a good electrochemical stability versus lithium electrodes as revealed by linear sweep voltammetry. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 46949.     

Heterocyclisch substituierte Arendiazoniumsalze mit erweiterter spektraler Empfindlichkeit. II. 4-(1-Heterocycliden-2,3-diaza-prop-2-en-3-yl)-benzendia-zoniumtetrafluoroborate

Heterocyclic Substituted Arenediazonium Salts with a Long-wave-length Range of Sensitivity. II. 4-(1-Heterocycliden-2,3-diaza-prop-2-en-3-yl)-arenediazonium tetrafluoroborates The title compounds ( 3 ) are obtained by reaction of aromatic bis-diazonium salts with substituted 2-benzylidene-1,3-dithioles and 2-benzylidene-1,3-diselenole, respectively. The maximum of the long wave-length absorption band of 3 varies from 580 nm up to 665 nm depending on the structure of the compound. The quantum yields of the photolysis of the diazonium salts 3 are low (1 · 10⁻⁴ to 7 · 10⁻³). The azo dyes obtained from 3 with usual azo-couplers absorb in a shorter wave-length range than the corresponding diazonium salts themselves (hypso-coupling effect).     

Effect of electrolyte concentration on the properties of the electropolymerized polypyrrole films

The effect of electrolyte concentration on the electropolymerization of pyrrole was investigated by studies of conductivity, tensile strength, and absorption spectra, etc., of polypyrrole films prepared from electrolyte aqueous solutions. The electrolyte salts used in the studies include sodium p-toluenesulfonate (TsONa), NaClO₄, NaNO₃, and KCl. Cyclic voltammetry and elemental analysis were also performed in the studies of the effect of the NaNO₃ concentration. The conductivity, tensile strength, and the counteranion doping degree of conducting polypyrrole films increased obviously with increase of the electrolyte concentration of their polymerization solutions from 0.2 to 1 mol L⁻¹. Further increase of the concentration over 1 mol L⁻¹ has a weak effect on the further improvement of the film quality of polypyrrole. So, 1 mol L₋₁ was recommended for the electrolyte concentration of the polymerization aqueous solutions of pyrrole. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 65: 2739–2744, 1997