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A stable two-dimensional radical hydrogen-bonded metal–organic framework, constructed using a modified tetrathiafulvalene-tetrabenzoate ((2-Me)-H4TTFTB) linker and Cd2+ ions, exhibits a high electrical conductivity of 4.1 × 10−4 S m−1 and excellent photothermal conversion with a temperature increase of 137 °C in 15 s under the irradiation of a 0.7 W cm−2 808 nm laser. [ABSTRACT FROM AUTHOR]

Within this work we have investigated spiro‐based tetrathiafulvalenes (TTFs) obtained as mixtures of stereoisomers from racemic spiro[5.5]undeca‐1,8‐dien‐3‐one. Compared to previously described spiro‐TTFs, enantiomeric and diastereoisomeric forms have been here separated by chiral HPLC and fully characterized both experimentally and theoretically. The two types of spiro‐based chiral derivatives contain either one (2) or three (1) chiral centres out of each one is spiro‐type. Experimental CD, supported by TD‐DFT calculations, shows differences in the optical activity between the 1 and 2 and their intermediates. The low optical activity of 2 and 3 (spiro alone chirality) was attributed to the presence of two conformers in the solution (ax and eq) of opposite Cotton effect whereas in the case of 1 and 5 (spiro and stereogenic centres) the spiro chirality seems to be responsible of the Cotton effect in the high energy region whereas the R and S chirality in the low energy region. Racemic and enantiopure forms have been successfully used for the synthesis of charge transfer complexes with tetracyanoquinodimethane (TCNQ) based acceptors. [ABSTRACT FROM AUTHOR]

The synthesis of crystalline self-assembled materials starting from building blocks with a large degree of freedom is challenging. Furthermore, incorporating redox-active moieties in self-assembled metal–organic polyhedra is of the utmost interest to modulate the properties of the cavity through redox stimuli. Herein is presented the synthesis of a novel electroactive ligand bearing four coordinating moieties around an S-alkylated tetrathiafulvalene (TTF) scaffold. The redox behavior of the ligand is similar to that of a tetra-S-alkylated TTF. In the solid state, it presents a densely packed H-bonded 1D polymeric structure. Upon reaction with Cu(OAc)2 in the presence of dimethylformamide or dimethylacetamide, two novel M4L4-type metal–organic polyhedra (MOPs) bearing paddlewheel metal clusters as connecting nodes are obtained. The structural features and electrochemical properties of the ligand and the MOPs are discussed. Both MOPs adopt the same structure characterized by a tetrahedral arrangement of the four TTF moieties. [ABSTRACT FROM AUTHOR]

Derivatives of vinyl‐extended tetrathiafulvalene (TTF) functionalized with two 2,6‐dicyano‐λ5‐phosphinine units (3 a–c) have been successfully synthesized. Cyclic voltammograms of all the derivatives are composed of three pairs of redox waves. The first and second redox waves correspond to one‐electron transfer processes, in which the extended TTF moiety participated predominantly. The third redox wave corresponded to a two‐electron transfer process, in which the two 2,6‐dicyano‐λ5‐phosphinine units were involved. The redox potentials at which the tetracations of 3 a–c were generated were considerably more negative than expected, probably due to the formation of stable closed‐shell structures by conjugation between 2,6‐dicyano‐λ5‐phosphinine units. X‐ray structural analyses of 3 b, 3 c, and (3b2+)(Sb2Cl82−)(C6H5OCH3) revealed that the vinyl‐extended TTF moiety in all the compounds adopts an almost planar structure, while the phosphinine units are significantly rotated relative to the extended TTF plane. The fluorescence spectroscopy revealed that the emission intensity of 3 b was very small in both the neutral and oxidized states. [ABSTRACT FROM AUTHOR]

An enlarged version of the ubiquitous tetrathiafulvalene-tetrabenzoic acid is described, with 4,4′-biphenyl moieties as spacers between the coordination moieties and the electroactive core. The obtained rectangular ligand has a 14 × 22 Å2 size and is combined with Zn(II) under solvothermal conditions to yield a coordination polymer endowed with large cavities of ca. 15 × 11 Å2/10 × 10 Å2. The topology of the material is discussed in detail using the Points of Extension and Metals (PE&M) or the Straight-rod (STR) representation, and the sqc1121 or tfo topological type of the structure is observed, respectively. Its stability towards solvent removal and electrical properties are discussed. The material does not present any permanent porosity upon desolvation according to nitrogen sorption measurements at 77 K. Nevertheless, a significant increase in conductivity is observed on compressed pellets of the material upon post-synthetic oxidation with iodine. Raman spectroscopy combined with density functional theory (DFT) calculations has been used to characterize the oxidation state of tetrakis(4-carboxylic acid biphenyl)tetrathiafulvalene for coordination polymers. [ABSTRACT FROM AUTHOR]

Structurally well-defined small organic photothermal agents (PTAs) in the NIR-II biowindow (1000–1700 nm) have garnered considerable attention, but their rarity greatly limits their wide applications. Herein, we report a host–guest charge-transfer (CT) complex, TTF⊂TBox-12+, constructed by electron-deficient naphthalene diimide (NDI) cyclophane TBox-12+ and electron-rich guest tetrathiafulvalene (TTF) in 1 : 1 host/guest stoichiometry. Owing to strong CT absorption, TTF⊂TBox-12+ showed high NIR-II photothermal conversion efficiency in both aqueous solution and the solid state, and then was exploited as a high-performance PTA for antibacterial applications and seawater desalination. This work provides an insight for the development of new structurally well-defined NIR-II PTAs via host–guest CT interaction. [ABSTRACT FROM AUTHOR]

Herein we present a novel linear supramolecular polymeric structure formed in both the solution and solid state, utilizing the host–guest recognition motif between perethylated pillar[5]arene and tetrathiafulvalene. [ABSTRACT FROM AUTHOR]

A novel low-molecular-weight organogelator (1) based on thiacrown-cyclized tetrathiafulvalene has been synthesized through cross-coupling reaction of crown-fused 1,3-dithiole-2-one 3 and the thione 4 in the presence of triethyl phosphite. The molecular structure of 1 was fully characterized by nuclear magnetic resonance spectroscopy, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, and infrared spectroscopy. Gel-forming-ability experiments showed that the gelator could only form an opaque gel in dimethyl sulfoxide by sonication. The xerogel morphology observed by scanning electron microscopy showed an amorphous wrinkled structure. The gel exhibited varied responses to various external stimuli, including temperature, chemical oxidation, anions, and Na+ ions. [ABSTRACT FROM AUTHOR]

The light‐transmissive properties of a solid‐state tetrathiafulvalene radical cation‐bis(trifluoromethanesulfonyl)imide, 1‐C5⋅+ ⋅ NTf2−, underwent instantaneous changes in the short‐wave infrared (SWIR) region (1000–2500 nm) upon exposure to solvent vapor or the application of mechanostress at room temperature. The initial solid state of 1‐C5⋅+ ⋅ NTf2− exhibited strong absorption in the near‐infrared (NIR; 700–1000 nm) and SWIR regions, whereas the absorption in the SWIR region was significantly diminished in the stimulated state induced by dichloromethane vapor. Upon cessation of vapor stimulation, the solid state spontaneously and promptly reverted to its original state, characterized by absorption bands in the NIR/SWIR region. Moreover, the SWIR absorption was absent upon the application of mechanical stress using a steel spatula. The reversal was fast and occurred within 10 s. These changes were visualized using a SWIR imaging camera under 1450‐nm light irradiation. Experimental investigations demonstrated that the transparency to the SWIR light in the solid states was modulated through significant structural transformations of the associated radical cations, with transitions between columnar and isolated π‐dimer structures under ambient and stimulated conditions, respectively. [ABSTRACT FROM AUTHOR]

The light‐transmissive properties of a solid‐state tetrathiafulvalene radical cation‐bis(trifluoromethanesulfonyl)imide, 1‐C5⋅+ ⋅ NTf2−, underwent instantaneous changes in the short‐wave infrared (SWIR) region (1000–2500 nm) upon exposure to solvent vapor or the application of mechanostress at room temperature. The initial solid state of 1‐C5⋅+ ⋅ NTf2− exhibited strong absorption in the near‐infrared (NIR; 700–1000 nm) and SWIR regions, whereas the absorption in the SWIR region was significantly diminished in the stimulated state induced by dichloromethane vapor. Upon cessation of vapor stimulation, the solid state spontaneously and promptly reverted to its original state, characterized by absorption bands in the NIR/SWIR region. Moreover, the SWIR absorption was absent upon the application of mechanical stress using a steel spatula. The reversal was fast and occurred within 10 s. These changes were visualized using a SWIR imaging camera under 1450‐nm light irradiation. Experimental investigations demonstrated that the transparency to the SWIR light in the solid states was modulated through significant structural transformations of the associated radical cations, with transitions between columnar and isolated π‐dimer structures under ambient and stimulated conditions, respectively. [ABSTRACT FROM AUTHOR]

Sulfur K-edge XAS data provide a unique tool to examine oxidation states and covalency in electronically complex S-based ligands. We present sulfur K-edge X-ray absorption spectroscopy on a discrete redox-series of Ni-based tetrathiafulvalene tetrathiolate (TTFtt) complexes as well as on a 1D coordination polymer (CP), NiTTFtt. Experiment and theory suggest that Ni–S covalency decreases with oxidation which has implications for charge transport pathways. [ABSTRACT FROM AUTHOR]

Modulation of the ligands and coordination environment of metal–organic frameworks (MOFs) has been an effective and relatively unexplored avenue for improving the anode performance of lithium‐ion batteries (LIBs). In this study, three MOFs are synthesized, namely, M4(o‐TTFOB)(bpm)2(H2O)2 (where M is Mn, Zn, and Cd; o‐H8TTFOB is ortho‐tetrathiafulvalene octabenzoate; and bpm is 2,2′‐bipyrimidine), based on a new ligand o‐H8TTFOB with two adjacent carboxylates on one phenyl, which allows us to establish the impact of metal coordination on the performance of these MOFs as anode materials in LIBs. Mn‐o‐TTFOB and Zn‐o‐TTFOB, with two more uncoordinated oxygen atoms from o‐TTFOB8−, show higher reversible specific capacities of 1249 mAh g−1 and 1288 mAh g−1 under 200 mA g−1 after full activation. In contrast, Cd‐o‐TTFOB shows a reversible capacity of 448 mAh g−1 under the same condition due to the lack of uncoordinated oxygen atoms. Crystal structure analysis, cyclic voltammetry measurements of the half‐cell configurations, and density functional theory calculations have been performed to explain the lithium storage mechanism, diffusion kinetics, and structure‐function relationship. This study demonstrates the advantages of MOFs with high designability in the fabrication of LIBs. [ABSTRACT FROM AUTHOR]

Keywords: tetrathiafulvalene; pyrrole; orthogonal building block; Sonogashira- coupling; alkylation EN tetrathiafulvalene pyrrole orthogonal building block Sonogashira- coupling alkylation 2019 2026 8 06/16/23 20230704 NES 230704 Tetrathiafulvalene (TTF, B 1 b ) and its derivatives (Figure 1) have been extensively investigated for half a century. The residue was purified by column chromatography (50 mL SiO SB 2 sb , deact. with 1% Et SB 3 sb N, 3 cm , eluent: CH SB 2 sb Cl SB 2 sb /EtOAc (9:1->4:1)). The crude product was purified by column chromatography (125 mL SiO SB 2 sb , deact. with 1% Et SB 3 sb N, 5 cm , eluent: CH SB 2 sb Cl SB 2 sb /PE (2:1)). The residue was purified by column chromatography (25 mL SiO SB 2 sb , deact. with 1% Et SB 3 sb N, 3 cm , eluent: PE/CH SB 2 sb Cl SB 2 sb (2:1 -> 1:1)). [Extracted from the article]

Modulation of the ligands and coordination environment of metal–organic frameworks (MOFs) has been an effective and relatively unexplored avenue for improving the anode performance of lithium‐ion batteries (LIBs). In this study, three MOFs are synthesized, namely, M4(o‐TTFOB)(bpm)2(H2O)2 (where M is Mn, Zn, and Cd; o‐H8TTFOB is ortho‐tetrathiafulvalene octabenzoate; and bpm is 2,2′‐bipyrimidine), based on a new ligand o‐H8TTFOB with two adjacent carboxylates on one phenyl, which allows us to establish the impact of metal coordination on the performance of these MOFs as anode materials in LIBs. Mn‐o‐TTFOB and Zn‐o‐TTFOB, with two more uncoordinated oxygen atoms from o‐TTFOB8−, show higher reversible specific capacities of 1249 mAh g−1 and 1288 mAh g−1 under 200 mA g−1 after full activation. In contrast, Cd‐o‐TTFOB shows a reversible capacity of 448 mAh g−1 under the same condition due to the lack of uncoordinated oxygen atoms. Crystal structure analysis, cyclic voltammetry measurements of the half‐cell configurations, and density functional theory calculations have been performed to explain the lithium storage mechanism, diffusion kinetics, and structure‐function relationship. This study demonstrates the advantages of MOFs with high designability in the fabrication of LIBs. [ABSTRACT FROM AUTHOR]

Tetrathiafulvalene is among the best known building blocks in molecular electronics due to its outstanding electron‐donating and redox properties. Among its derivatives, dithiophene‐tetrathiafulvalene (DT‐TTF) has attracted considerable interest in organic electronics, owing to its high field‐effect mobility. Herein, we report the direct C−H arylation of DT‐TTF to synthesise mono‐ and tetraarylated derivatives functionalised with electron‐withdrawing and electron‐donating groups in order to evaluate their influence on the electronic properties by cyclic voltammetry, UV‐vis spectroscopy and theoretical calculations. Self‐assembly of the DT‐TTF‐tetrabenzoic acid derivative was studied by using scanning tunnelling microscopy (STM) which revealed the formation of ordered, densely packed 2D hydrogen‐bonded networks at the graphite/liquid interface. The tetrabenzoic acid derivative can attain a planar geometry on the graphite surface due to van der Waals interactions with the surface and H‐bonding with neighbouring molecules. This study demonstrates a simple method for the synthesis of arylated DT‐TTF derivatives towards the design and construction of novel π‐extended electroactive frameworks. [ABSTRACT FROM AUTHOR]

A great proportion of molecular crystals can be made to grow as twisted fibrils. Typically, this requires high crystallization driving forces that lead to spherulitic textures. Here, it is shown how micron size channels fabricated from poly(dimethylsiloxane) (PDMS) serve to collimate the circular polycrystalline growth fronts of optically banded spherulites of twisted crystals of three compounds, coumarin, 2,5‐bis(3‐dodecyl‐2‐thienyl)‐thiazolo[5,4‐d]thiazole, and tetrathiafulvalene. The relationships between helicoidal pitch, growth front coherence, and channel width are measured. As channels spill into open spaces, collimated crystals "diffract" via small angle branching. On the other hand, crystals grown together from separate channels whose bands are out of phase ultimately become a single in‐phase bundle of fibrils by a cooperative mechanism yet unknown. The isolation of a single twist sense in individual channels is described. We forecast that such chiral molecular crystalline channels may function as chiral optical wave guides. [ABSTRACT FROM AUTHOR]

The extreme sensitivity of trivalent lanthanide ions to crystal field variations led to the emergence of single‐molecule magnetic switching under various stimuli. The use of pressure as an external stimulus instead of classic light irradiation, oxidation or any chemical reactions allows a fine tuning of the magnetic modulation. Here the well‐known pure isotopically enriched [162Dy(tta)3(L)]⋅C6H14 (162Dy) Single‐Molecule Magnet (SMM) (tta−=2‐2‐thenoyltrifluoroacetonate and L=4,5‐bis(propylthio)‐tetrathiafulvalene‐2‐(2‐pyridyl)benzimidazole‐methyl‐2‐pyridine) was experimentally investigated by single‐crystal diffraction and squid magnetometry under high applied pressures. Both reversible piezochromic properties and pressure modulation of the slow magnetic relaxation behavior were demonstrated and supported by ab initio calculations. The magnetic study of the diluted sample [162Dy0.05Y0.95(tta)3(L)]⋅C6H14 (162Dy@Y) indicated that variations in the electronic structure have mainly intermolecular origin with weak intramolecular contribution. Quantitative magnetic interpretation concludes to a deterioration of the Orbach process for the benefit of both Raman and QTM mechanisms under applied pressure. [ABSTRACT FROM AUTHOR]

Tetrathiafulvalene (TTF) and Ni‐bis(dithiolene) are typical conductive units widely studied in electronics, optics, and photochemistry. However, their applications in near‐infrared (NIR) photothermal conversion are often limited by insufficient NIR absorption and low chemical/thermal stability. Herein, we integrate TTF and Ni‐bis(dithiolene) into a covalent organic framework (COF) with stable and efficient NIR and solar photothermal conversion performance. Two isostructural COFs, namely Ni‐TTF and TTF‐TTF, are successfully isolated which are composed of TTF and Ni‐bis(dithiolene) units as donor‐acceptor (D−A) pairs or TTF units only. Both COFs show high BET surface areas and good chemical/thermal stability. Notably, compared with TTF‐TTF, the periodic D−A arrangement in Ni‐TTF significantly lowers the bandgap, leading to unprecedented NIR and solar photothermal conversion performance. [ABSTRACT FROM AUTHOR]

Harnessing a bis(selenomethyl)tetrathiafulvalene (TTF) derivative as a donor, conducting charge transfer (CT) salts are realized thanks to original packing structures supported by chalcogen bonding (ChB) interactions. Specifically, reaction of EDT-TTF(SeMe)2 (EDT = ethylenedithio) with an acceptor, 2,5-difluoro-7,7,8,8-tetracyanoquinodimethane (F2TCNQ), afforded two polymorphs of 1 : 1 CT salts, α- and β-[EDT-TTF(SeMe)2](F2TCNQ). The donor and the acceptor molecules in both polymorphs organize into segregated and uniform stacks. Based on the structure, the α-salt shows a quasi-complete CT while the β-salt shows a partial CT with ρ ∼±0.8. The oxidation of TTF activates the σ-hole on Se atoms to be engaged in highly linear ChB interactions with the N atoms on F2TCNQ. The formation of directional ChB interactions resulted in original packing structures of the donor and the acceptor stacks that are distinct between α- and β-salts. In particular, the ChB motif observed in the β-salt allows F2TCNQ molecules within the stack to be closer than those in the α-salt. Consequently, the α-salt is a semi-conductor, while the β-salt shows metallic behaviour with a two-step metal-to-insulator (MI) transition. Moreover, the observed MI transition temperature in the β-salt (180 K) is substantially higher than that in other known CT salts, likely owing to the 3D coupling of the modulation in different chains brought about by the –SeMe substituents. [ABSTRACT FROM AUTHOR]

The palladium-catalyzed cross-coupling of the lithium anion of aryl tert -butyldimethylsilyl-protected cyanohydrins with aryl bromides followed by in situ deprotection with fluoride ion provides a convenient and versatile approach to biaryl ketones. This protocol represents the first example of a palladium-catalyzed arylation of a cyanohydrin, which functions as an acyl anion equivalent. Hence, in contrast to classical cross-coupling reactions, the pronucleophile component is incorporated in the product to permit further functionalization. We then highlight the synthetic utility of the new method with applications to bioactive biaryl ketones and the construction of a triaryl diketone that has been used to prepare an extended tetrathiafulvalene. [ABSTRACT FROM AUTHOR]

Pillar[5]arene derivatives decorated with ten peripheral TTF subunits have been efficiently prepared from a decabrominated pillar[5]arene building block and appropriate TTF–thiolate nucleophiles. While the preparation of related systems with peripheral exTTF subunits could not be achieved under the same conditions, a fully substituted pillar[5]arene exTTTF conjugate has been prepared from a clickable pillar[5]arene derivative and an exTTF derivative bearing a terminal alkyne function. Electrochemistry investigations have revealed substantial electronic interactions between the TTF subunits in the conjugates. The peripheral TTF moieties are indeed confined in a restricted space and thus forced to interact. In contrast, no electronic interactions could be detected for the exTTF-containing system. Finally, binding studies have shown all the conjugates are capable of forming host–guest complexes with 1,6-dicyanohexane and a methanofullerene bearing a cyanoalkane moiety. [ABSTRACT FROM AUTHOR]

Unsymmetrical gold(III)‐dithiolene complexes are potential candidates for molecular materials that exhibit thermal structural phase transitions. In this study, unsymmetrical ppy‐gold(III) (ppy−=C‐deprotonated‐2‐phenylpyridine(−)) complexes [AuC5] and [AuC6] coordinated by dithiolene ligands containing tetrathiafulvalene (TTF) skeletons with pentylthio (2‐{bis(pentylthio)‐1,3‐dithiol‐2‐ylidene}‐1,3‐dithiol‐4,5‐dithiolate(2−)) and hexylthio groups (2‐{bis(hexylthio)‐1,3‐dithiol‐2‐ylidene}‐1,3‐dithiol‐4,5‐dithiolate(2−)) were synthesized. Both complexes exhibited a large absorption band at approximately 508 nm, owing to intramolecular ligand‐to‐ligand charge transfer. One‐dimensional columnar structures with head‐to‐tail molecular arrangements around the metal ions were constructed in the crystals. The flexible alkylthio groups were intercalated into crystalline spaces between dithiolene ligands in the columns. [AuC5] exhibits a simple phase transition at 198 °C between crystalline and isotropic phases irreversibly. The crystalline phase of [AuC6] observed at 25 °C melted at 148 °C. Another crystalline phase grew above 148 °C with a very slow crystallization rate from the liquid phase and was completely transformed into an isotropic phase at 200 °C. [ABSTRACT FROM AUTHOR]

Lithium-ion batteries are attractive for their use in portable electronics and electric vehicles owing to their high energy and power density. Organic materials as active materials for the positive electrode have attracted attention as an alternative to inorganic materials in sustainable batteries. However, there is a serious drawback that elution into the electrolyte solution. This article describes our attempts in the development of tetrathiafulvalene (TTF) analogs for active materials. We have developed four types of fused TTF systems; multifused TTF systems, TTF analogs extended with cyclohexene moieties, TTF analogs extended with an anthraquinoid spacer, and fused TTF and benzoquinone systems. These molecules were designed based on the idea that increasing the size and planarity of the molecules and intermolecular interactions. They were successfully synthesized and their cell performances were clarified. We also describe that a TTF analog bearing triphenylamines was applied to long-cycle-life electrodes as a recent effort. This molecule was successfully synthesized using palladium-catalyzed C-H arylation and the cycle life of the cells comprising this molecule was markedly improved by in-cell electropolymerization. [ABSTRACT FROM AUTHOR]

The lack of understanding for precise synthesis and assembly of nano‐entities remains a major challenge for nanofabrication. Electrocrystallization of a charge‐transfer complex (CTC), tetrathiafulvalene bromide (TTF)Br, is studied on micro/nanoelectrodes for precision deposition of functional materials. The study reveals new insights into the entire CTC electrocrystallization process from the initial nanocluster nucleation to the final elongated crystals with hollow ends grown from the working electrode to the neighboring receiving electrode. On microelectrodes, the number of nucleation sites is reduced to one by lowering the applied overpotential or precursor concentration. Certain current–time transients exhibit significant induction periods prior to stable nucleus growth. The induction regime contains small fluctuating current spikes consistent with stochastic formation of precritical nanoclusters with lifetimes of 0.1–30 s and sizes of 20–160 nm. Electrochemical analyses further reveal rate, size distribution, and formation/dissipation dynamics of the nanoclusters. Crystal growth of (TTF)Br is further studied on triangular nanoelectrode patterns with thickness of 5–500 nm, which shows a mass‐transfer‐controlled process applicable for precision deposition of functional (TTF)Br crystals. This study, for the first time, establishes CTC nanoelectrochemistry as a platform technology for precise deposition of conductive crystal assemblies spanning the source and drain electrode for sensing applications. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs), with diverse metal nodes and designable organic linkers, offer unique opportunities for the rational engineering of semiconducting properties. In this work, we report a mixed‐linker conductive MOF system with both tetrathiafulvalene and Ni‐bis(dithiolene) moieties, which allows the fine‐tuning of electronic structures and semiconductive characteristics. By continuously increasing the molar ratio between tetrathiafulvalene and Ni‐bis(dithiolene), the switching of the semiconducting behaviors from n‐type to p‐type was observed along with an increase in electrical conductivity by 3 orders of magnitude (from 2.88×10−7 S m−1 to 9.26×10−5 S m−1). Furthermore, mixed‐linker MOFs were applied for the chemiresistive detection of volatile organic compounds (VOCs), where the sensing performance was modulated by the corresponding linker ratios, showing synergistic and nonlinear modulation effects. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs), with diverse metal nodes and designable organic linkers, offer unique opportunities for the rational engineering of semiconducting properties. In this work, we report a mixed‐linker conductive MOF system with both tetrathiafulvalene and Ni‐bis(dithiolene) moieties, which allows the fine‐tuning of electronic structures and semiconductive characteristics. By continuously increasing the molar ratio between tetrathiafulvalene and Ni‐bis(dithiolene), the switching of the semiconducting behaviors from n‐type to p‐type was observed along with an increase in electrical conductivity by 3 orders of magnitude (from 2.88×10−7 S m−1 to 9.26×10−5 S m−1). Furthermore, mixed‐linker MOFs were applied for the chemiresistive detection of volatile organic compounds (VOCs), where the sensing performance was modulated by the corresponding linker ratios, showing synergistic and nonlinear modulation effects. [ABSTRACT FROM AUTHOR]

The full reaction photosynthesis of H2O2 that can combine water‐oxidation and oxygen‐reduction without sacrificial agents is highly demanded to maximize the light‐utilization and overcome the complex reaction‐process of anthraquinone‐oxidation. Here, a kind of oxidation‐reduction molecular junction covalent‐organic‐framework (TTF‐BT‐COF) has been synthesized through the covalent‐coupling of tetrathiafulvalene (photo‐oxidation site) and benzothiazole (photo‐reduction site), which presents visible‐light‐adsorption region, effective electron‐hole separation‐efficiency and photo‐redox sites that enables full reaction generation of H2O2. Specifically, a record‐high yield (TTF‐BT‐COF, ≈276 000 μM h−1 g−1) for H2O2 photosynthesis without sacrificial agents has been achieved among porous crystalline photocatalysts. This is the first work that can design oxidation‐reduction molecular junction COFs for full reaction photosynthesis of H2O2, which might extend the scope of COFs in H2O2 production. [ABSTRACT FROM AUTHOR]

The full reaction photosynthesis of H2O2 that can combine water‐oxidation and oxygen‐reduction without sacrificial agents is highly demanded to maximize the light‐utilization and overcome the complex reaction‐process of anthraquinone‐oxidation. Here, a kind of oxidation‐reduction molecular junction covalent‐organic‐framework (TTF‐BT‐COF) has been synthesized through the covalent‐coupling of tetrathiafulvalene (photo‐oxidation site) and benzothiazole (photo‐reduction site), which presents visible‐light‐adsorption region, effective electron‐hole separation‐efficiency and photo‐redox sites that enables full reaction generation of H2O2. Specifically, a record‐high yield (TTF‐BT‐COF, ≈276 000 μM h−1 g−1) for H2O2 photosynthesis without sacrificial agents has been achieved among porous crystalline photocatalysts. This is the first work that can design oxidation‐reduction molecular junction COFs for full reaction photosynthesis of H2O2, which might extend the scope of COFs in H2O2 production. [ABSTRACT FROM AUTHOR]

To construct novel ion receptors and D-A self-assembly systems for materials with better functions, the annulation of a tetrathiafulvalene donor with a magnesium norphthalocyanine core via a flexible tetrathiacrown ether bridge afforded a new triad 1. The structure of this product was characterized by 1H NMR and infrared spectroscopy, time-of-flight mass spectrometry, and elemental analysis. The optical and electrochemical properties were investigated using UV–vis spectroscopy and cyclic voltammetry. The complex of triad 1 and 2,3,5,6- tetrafluoro-7,7,8,8-tetracyanoquinodimethane produced electron transfer with a radical cationic character, as confirmed by UV–Vis and electron paramagnetic resonance analysis. Furthermore, the target compound presented evident intramolecular charge-transfer interactions in ground states, which were explained using density functional theory. Furthermore, norphthalocyanine 1 was able to coordinate Ag+ through the peripheral ligating oxathiaether crown. [ABSTRACT FROM AUTHOR]

Two hybrid bonded hydrogen-bonded organic frameworks (namely PTP-HOF3 and PTP-HOF4) based on tetrathiafulvalene (TTF) exhibit good electrical- and photo-conductivity. PTP-HOF4 with proton transfer characteristics shows a more regular porosity with a size of 14.35 Å × 8.75 Å and better conductivity than PTP-HOF3. [ABSTRACT FROM AUTHOR]

Supramolecular gels and liquid crystals are two important organic soft materials in self-assembly systems. A series of new low-molecular-weight organic gels was synthesized by connecting two cholesterol molecules and two hydrophobic chains incorporating amide groups to a central tetrathiafulvalene (TTF) moiety (1a–l). Compounds 1a–l and their corresponding charge transfer complexes easily formed a stable supramolecular gel in various organic solvents and their self-assembly morphologies and structures were investigated. It was revealed that hydrogen bonding and van der Waals interaction played important roles in the gelation process. More importantly, nearly half of the gelators exhibited liquid crystalline phases of type smectic A in a particular temperature region; there was no crystallization but there was vitrifying to form glassy mesogens during cooling from the isotropic melt. The effects of the linker chain length and terminal alkoxy chain on liquid crystals were studied. The liquid crystalline organogelator with TTF unit was first designed and synthesized. It was demonstrated that the gelators obtained from cyclohexane had a strong ability to adsorb the toxic dye Rhodamine B from water. This property of this series of compounds is considered to have potential utilization for the removal of toxic dye molecules from wastewater. [ABSTRACT FROM AUTHOR]

Chalcogen bonding (ChB) interactions are investigated in two new –SeMe substituted tetrathiafulvalene (TTF) derivatives, RTTF(SeMe)2 (R = Me2, SCH2CH2S). Upon oxidation to 1 : 1 cationic radical salts, Se atoms are engaged in highly linear ChB interactions with bromide anions, demonstrating the efficient σ-hole activation of selenium through redox-active substituents. [ABSTRACT FROM AUTHOR]

A rare case of semiconducting actinide-based metal–organic framework SCU-125 was designed and synthesized. As a result of the lack of two coordination sites in the plane of the tetrathiafulvalene tetrabenzoate (TTFTB) molecule, a defective kgd network was formed. The electrical conductivity of SCU-125 was measured to be 2.2(2) × 10−7 S cm−1 at 25 °C ± 2 °C. [ABSTRACT FROM AUTHOR]

The synthesis of a tetrathiafulvalene (TTF) derivative, S-[4-({4-[(2,2′-bi-1,3-dithiol-4-ylmethoxy)methyl] phenyl}ethynyl)phenyl] ethanethioate, suitable for the modification of gold nanoparticles (AuNPs), is described in this article. The TTF ligand was self-assembled on the AuNP surface through ligand exchange, starting from dodecanethiol-stabilized AuNPs. The resulting modified AuNPs were characterized by TEM, UV-Vis spectroscopy, and electrochemistry. The most suitable electrochemical method was the phase-sensitive AC voltammetry at very low frequencies of the sine-wave perturbation. The results indicate a diminishing electronic communication between the two equivalent redox centers of TTF and also intermolecular donor–acceptor interactions manifested by an additional oxidation wave upon attachment of the ligand to AuNPs. [ABSTRACT FROM AUTHOR]

Chiral bis(TTF) diamides have been obtained in good yields (54–74%) from 1,2-cyclohexane-diamine and the corresponding TTF acyl chlorides. The (R,R)-1 and (S,S)-1 enantiomers have been characterized by circular dichroism and the racemic form by single-crystal X-ray diffraction. The neutral racemic bis(TTF)-diamide shows the formation of a pincer-like framework in the solid state, thanks to the intramolecular S···S interactions. The chemical oxidation in a solution using FeCl3 provides stable oxidized species, while the electrocrystallization experiments provided radical cation salts. In particular, single-crystal resistivity measurements on the racemic donor with AsF6− as a counterion demonstrate semiconductor behavior in this material. The DFT and TD-DFT calculations support the structural and chiroptical features of these new chiral TTF donors. [ABSTRACT FROM AUTHOR]

Metal-organic frameworks (MOFs) constructed by tetrathiafulvalene-tetrabenzoate (H4TTFTB) have been widely studied in porous materials, while the studies of other TTFTB derivatives are rare. Herein, the meta derivative of the frequently used p-H4TTFTB ligand, m-H4TTFTB, and lanthanide (Ln) metal ions (Tb3+, Er3+, and Gd3+) were assembled into three novel MOFs. Compared with the reported porous Ln-TTFTB, the resulted three-dimensional frameworks, Ln-m-TTFTB ([Ln2(m-TTFTB)(m-H2TTFTB)0.5(HCOO)(DMF)]·2DMF·3H2O), possess a more dense stacking which leads to scarce porosity. The solid-state cyclic voltammetry studies revealed that these MOFs show similar redox activity with two reversible one-electron processes at 0.21 and 0.48 V (vs. Fc/Fc+). The results of magnetic properties suggested Dy-m-TTFTB and Er-m-TTFTB exhibit slow relaxation of the magnetization. Porosity was not found in these materials, which is probably due to the meta-configuration of the m-TTFTB ligand that seems to hinder the formation of pores. However, the m-TTFTB ligand has shown to be promising to construct redox-active or electrically conductive MOFs in future work. [ABSTRACT FROM AUTHOR]

Tetrathiafulvalene (TTF) is a highly tunable electron donor that has been widely studied in charge transfer (CT) complexes, including Bechgaard salts which are superconductors at low temperatures. Its close relative, tetrathianaphthalene (TTN) has received considerably less attention than its TTF counterpart but is potentially a versatile electron donor. Three novel CT complexes containing mixed and segregated stack donor-acceptor (D–A) complexes of tetrathiafulvalene (TTF), tetrathianaphthalene (TTN) and naphthalene diimide (NDI) are reported. We demonstrate a facile mechanochemical synthesis of two salts, TTF–DPNI and TTN–DPNI (DPNI = N,N′-di-(4-pyridyl)-1,4,5,8-naphthalenetetracarboxydiimide), which is uncommon for these materials. Despite the detection of a very low partial charge transfer in the three salts using UV-Vis-NIR, Raman and EPR spectroscopies, we elucidated the properties of the TTN core with support from DFT calculations for the first time. We highlight the performance of TTN in a CT complex and demonstrate the importance of a combined approach to the characterisation of CT in organic D–A complexes. [ABSTRACT FROM AUTHOR]

A technique to establish electrical contact and perform multi-probe electrical measurements (e.g., four-probe measurements), even at low temperatures, is presented in this work. The natural adhesion contact (NAC) is applicable to the wide range of dimensions of organic crystals. Furthermore, the precise electrode patterns required to carry out multi-probe measurements are guaranteed, in contrast to fine conductive paste painting methods. We demonstrate four-probe electrical measurements of α -(BEDT-TTF) 2 I 3 (where BEDT-TTF = bis(ethylenedithio) tetrathiafulvalene) at temperatures down to 100 K. The obtained temperature dependence showed a steep meta l–insulator transition and exhibited zero hysteresis throughout several measurement sequences. [ABSTRACT FROM AUTHOR]

Topological coindices are generally utilized for quantitative structure-action relationship (QSAR) and quantitative structure property relationship (QSPR). Topological coindices are topological indices that considers the non contiguous sets of vertices. Here, we consider the accompanying some well-known topological coindices: Randic coindices, the first and second Zagreb coindices, the first and second multiplicative Zagreb coindices, the F-coindex, Atom bond connectivity Coindex, Geometric arithmetic Coindex and General Randic conidex. By utilizing graph basic investigation and deduction, we study the previously mentioned topological coindices of some synthetic atomic graphs that as often as possible show up in clinical, synthetic, and material designing. In this paper, we discuss the Polycyclic Tetrathiafulvalene and Polycyclic Oragano Silicon Dendrimers and acquire the calculation formulae of the coindices of these networks. [ABSTRACT FROM AUTHOR]

We have developed a two-step synthesis of dibenzotetrathiafulvalene (DBTTF) derivatives by combining the indium-catalyzed reductive dithioacetalization of oxalic acid and electron-rich aromatic dithiols with a subsequent oxidation of the resultant dithioacetals. The same transformation of electron-rich aromatic dithiols with either 9-fluorenecarboxylic acid derivatives or dicarboxylic acids effectively produced the corresponding benzo-1,3-dithiafulvene derivatives. [ABSTRACT FROM AUTHOR]

Tetrathiafulvalene (TTF) was successfully applied to degrade rhodamine 6G (Rh6G) in photocatalytic system. The results exhibited that TTF had excellent suitability in the range of weak acid to weak base (pH = 5–9). Multiple reactive oxygen species (˙OH, 1O2, H2O2 and ˙O2−) as well as h+ and e− were generated in photocatalytic process, causing the rapid degradation of Rh6G. This study provides new ideas for the development of catalysts in photocatalytic system and the broader applications of organic semiconductor materials. [ABSTRACT FROM AUTHOR]

A series of charge-transfer (CT) complexes have been prepared via diffusion and evaporation methods comprising arylthio-substituted tetrathiafulvalene (Ar-S-TTF) derivatives 1 – 5 and TCNQF4. Crystallographic studies revealed the diverse crystal packing of the CT complexes, which is related to their flexible structure and the planar central cores of the Ar-S-TTF. The complexes could be divided into three systems according to the packing similarities and dissimilarities of Ar-S-TTF (donor, D) and TCNQF4 (acceptor, A), namely Class 1 (D on D and A on A segregated stacking), Class 2 ((–A–D–) n mixed stacking) and Class 3 (–D–D–D–D– and A, A stacks with each other in edge-to-face interactions between cations and anions). The presence of multiple intermolecular interactions promotes the formation of various stacking structures. There are two factors affecting the packing structures and compositions of the CT complexes: (1) the aryl groups thereon of Ar-S-TTF; and (2) the expanded π-conjugated system. Charge-transfer (CT) complexes formed between Ar-S-TTFs and TCNQF4 are investigated. It is found that the complexes show different degrees of charge transfer and the stacking structures of the CT complexes can be manipulated by varying the symmetry and size of the aryl groups on the Ar-S-TTF. [ABSTRACT FROM AUTHOR]

Based on protonic-defected dicarboxylic acid, a simple pure organic single-component molecular conductor, [HEDT-TTF-dc] has been successfully synthesized. The neutral HEDT-TTF-dc molecules form two-dimensional conducting layers, which are connected by hydrogen bond interaction. The electrical resistivity measurement exhibits a semiconducting behavior with a low activation energy of 0.1 eV. The magnetic susceptibility can be fit by the singlet-triplet model, which provides with the small energy gap corresponding to the activation energy. Based on protonic-defected dicarboxylic acid, a simple pure organic single-component molecular conductor, [HEDT-TTF-dc] has been successfully synthesized. The neutral HEDT-TTF-dc molecules form two-dimensional conducting layers, which are connected by hydrogen bond interaction. The electrical resistivity measurement exhibits a semiconducting behavior with a low activation energy of 0.1 eV. The magnetic susceptibility can be fit by the singlet-triplet model, which provides with the small energy gap corresponding to the activation energy. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • We synthesized novel liquid crystal gelators with cholesterol and thiacrown-annelated tetrathiafulvalenes moieties. • Compounds 1b and 1d formed stable gels and exhibited nematic liquid crystalline phases with different nanostructures. • The gels 1d obtained from n-hexane readily adsorbed the toxic dye rhodamine B from water. We synthesized a series of novel liquid crystal (LC) gelators by attaching two cholesterol groups through two ω-thioalkanoyloxy spacers of varying length to thia-crown-annulated tetrathiafulvalene (TTF) moieties (1a – e). Among these compounds, 1b and 1d underwent gelation to form stable supramolecular gels in various organic solvents, and their self-assembled morphology and structure indicated that Van der Waals interactions were the driving force of gel formation. In addition, more than half of the gels (1a – d) transformed into nematic LCs in a certain temperature range, while gelators that did not crystallize during cooling from the isotropic melt formed glassy mesogens. Notably, gelators obtained from n -hexane readily adsorbed rhodamine B in solution, which was considered useful for removing toxic dye molecules in wastewater. LC molecules described herein were capable of gelation and have useful oxidation and stimulus-responsive properties. They may therefore be useful for developing sensors and optoelectronic materials. [ABSTRACT FROM AUTHOR]

Photoswitchable small molecules, such as N,N'‐disubstituted indigos, have received great interest within fields such as pharmacology, energy storage, and functional materials, as they represent key building blocks for reversible and non‐invasive control of chemical processes. However, to ensure applicability of photochromic systems it is of paramount importance to manipulate the photostationary state. In this work, we achieved this by tethering two redox‐active indenofluorene‐extended tetrathiafulvalene units to an N,N'‐disubstituted indigo photoswitch. Upon two‐electron oxidation, we observe significantly enhanced stability of the Z‐isomer, compared to the neutral compound, illustrated by a substantial increase in the half‐life from 0.48 seconds to 22 hours. This remarkable stabilization is ascribed to formation of strong, intramolecular π‐dimers between the oxidized subunits. [ABSTRACT FROM AUTHOR]

Tetrathiafulvalene (TTF) and its analogs are fascinating molecules in materials science based on their excellent electron‐donating abilities. This personal account describes recent advances in the synthesis of TTF analogs for functional materials via the palladium‐catalyzed modification of peripheries of TTF analogs. We first consider three types of molecules: fluorophore‐TTF hybrid molecules, multi‐redox systems, and an organic ligand for metal‐organic frameworks. These molecules were successfully synthesized via Stille coupling or palladium‐catalyzed direct C−H arylation and their structural, electrochemical, and optical properties were clarified. Subsequently, phosphorus‐substituted TTF analogs were successfully synthesized for future applications of redox‐active phosphine ligands for metal catalysts. The development of these molecules can significantly affect the advancement of chemical science. [ABSTRACT FROM AUTHOR]

A new tetrathiafulvalene (TTF) electron-donor molecule fused with 2-oxo-4-amino-pyrimido (cytosine) ring was synthesized. The electrochemical measurement revealed that the deprotonation on the pyrimido-ring greatly strengthened the electron-donating ability of the TTF skeleton. The neutral betainic radical in which the cytosine and TTF skeleton were the deprotonated anion and radical cation, respectively, exhibited a high conductivity of ∼10−3 S cm−1 as a single-component organic molecule. In the crystal structure of the salt composed of 1:1 composite of neutral and deprotonated anion formed a new self-assembling structure of cytosine, a hemi-deprotonated cytosine pair, through triple complementary hydrogen-bonds. [ABSTRACT FROM AUTHOR]

Three tetrathiafulvalene (TTF)-functionalized thiophene (Th) monomers with different σ bridges were synthesized. The UV–Vis spectra and CV implied that the weak intramolecular charge transfer effects existed in these monomers. They could be electropolymerized into the polythiophenes with TTF unit as pendant group during the CV and CA processes, while the electropolymerization of non-TTF-substituted thiophenes failed under the same conditions. The electropolymerized P (TTF-σ-Th) exhibited good electrochromic performances, especially in P (TTF-Th-3), due to the thiophene backbone activated by the TTF group. Novel Tetrathiafulvalene-σ-Thiophenes monomers were successfully electropolymerized with good electrochromic performance due to the activation effect of TTF pendent. [ABSTRACT FROM AUTHOR]

Redox active tetrathiafulvalene (TTF) and its derivatives when used as electrode additives have exhibited improved energy efficiency and sustainability in batteries. However, the structure–property relationship has not been investigated in detail until very recently. In this work, three redox-active TTF compounds were synthesized, and formulated as [Cu(HL)2(bpa)2]n (1), [Cu(bpe)2(H2O)2]n·2n(HL)·nMeOH·nH2O (2), and [Cu(bpp)2(H2O)2]n·2n(HL) (3) (L = dimethylthio-tetrathiafulvalene-bicarboxylate) for this work. The effects of conjugated state and spacer length of the linkers on structural assembly and band gap as well as the interactions of TTF–TTF/TTF-bpy are discussed. Compound 1 is a bpa and HL co-coordinated 1D Cu(II) polymer. Compounds 2 and 3 are 2D Cu(II)-bipyridine (4,4) MOFs incorporating HL (1−) as free anion columns. The photocurrent density of 2 is larger than those of 1 and 3 due to a strong charge transfer from TTF to bpe in compound 2. The supercapacitance performances of these compounds were evaluated by cyclic voltammetry (CV) and galvanostatic charge–discharge (GCD) techniques. The results revealed that the 2D MOF structures of 2 and 3 are beneficial for good specific capacitance values (Csp). This work revealed the structure–property relationships of TTF derivatives for use as electrode active materials in energy transfer and storage. [ABSTRACT FROM AUTHOR]

[Display omitted] • TTF-pm was used as buffer layers in PTB7-Th:PC71BM organic solar cells for the first time. • The device based on these bilayered HTLs yielded a notably high FF of 74.05%. • The TTF-pm film can also be employed in PM6:Y6 non-fullerene solar cells as a result of efficient interfacial modification. Interface engineering has been widely proved to be an effective approach to improving the overall efficiency of organic solar cells (OSCs). Among the enhanced photovoltaic parameters, a high fill factor (FF) is more responsible for a stable and efficient device. Herein, a simple and effective strategy with a view to improving the FF is demonstrated by modification of hole transporting layers (HTLs). By using a non-planar conjugated tetrathiafulvalene derivative (named TTF-pm) and poly (3,4-ethylenedioxythiophene): polystyrene sulfonate (PEDOT:PSS) as double HTLs, the conventional device based on PTB7-Th:PC 71 BM bulk heterojunction delivers a boosted power conversion efficiency (PCE) of 9.80% and an impressive FF of 74.05%. The analyses presented indicate that the enhanced FF is mostly attributed to the optimized morphology of active layer, improved mobility and suppressed charge recombination via interfacial modification. Moreover, the device stability is also improved benefiting from the optimized film morphology. In addition, a PCE of 16.5% for non-fullerene organic solar cells based on PM6:Y6 blend film using the new HTLs is obtained, which is 7.8% higher than the control. This study highlights the potential of TTF derivatives as new HTLs for high and stable performance in the field of organic photovoltaics. [ABSTRACT FROM AUTHOR]