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Organic electrode materials are promising to be applied in sodium ion batteries (SIBs) due to their low cost and easily modified molecular structures. Nevertheless, low conductivity and high solubility in electrolytes still limit the development of organic electrodes. In this work, a carboxylate small molecule (BDTTS) based on tetrathiafulvalene is developed as anode material for SIBs. BDTTS has a large rigid π‐conjugated planar structure, which may reduce solubility in the electrolyte, meanwhile facilitating charge transporting. Experimental results and theoretical calculations both support that apart from the four carbonyl groups, the sulfur atoms on tetrathiafulvalene also provide additional active sites during the discharge/charge process. Therefore, the additional active sites can well compensate for the capacity loss caused by the large molecular weight. The as‐synthesized BDTTS electrode renders an excellent capacity of 230 mAh g−1 at a current density of 50 mA g−1 and an excellent long‐life performance of 128 mAh g−1 at 2 C after 500 cycles. This work enriches the study on organic electrodes for high‐performance SIBs and paves the way for further development and utilization of organic electrodes. [ABSTRACT FROM AUTHOR]

The study aims to predict and compare the structural, electronic, conductivity, and biological properties of a series of 3d transition element complexes with those of the previously studied isostructural copper complex [Cu(hfac)2(TTF)2][PF6]2 (TTF: tetrathiafulvalene, hfac: hexafluoroacetylacetonate). Because transition metals hold open electronic shells, all possible spin states for all divalent compounds have to be considered in order to determine the most stable configurations. These configurations are those corresponding to the highest spin state (5 for Mn, 4 for Fe, 3 for Co, 2 for Ni, 1 for Cu, and 0 for Zn). However, the configurations with the smallest gap are Mn(3) and Co(1), suggesting that these are the most conductive complexes. A significant metal–ligand charge transfer is observed for both Mn and Co complexes. Antifungal (CYP121 (PDB: 2IJ7) and CYP51 (PDB: 1EA1)) and antibacterial (Escherichia coli (PDB: 1KZN)) properties of the compounds studied were evaluated by molecular docking; the results obtained reveal that the following complexes show significant activity: Zn(hfac)2(TTF)2] [PF6]2 (−8.9 kcal/mol), Ni(hfac)2(TTF)2] [PF6]2 (−7.8 kcal/mol), and Cu(hfac)2(TTF)2] [PF6]2 (−8.2 kcal/mol). [ABSTRACT FROM AUTHOR]

Redox flow batteries (RFBs) with high energy densities are essential for efficient and sustainable long‐term energy storage on a grid scale. To advance the development of nonaqueous RFBs with high energy densities, a new organic RFB system employing a molecularly engineered tetrathiafulvalene derivative ((PEG3/PerF)‐TTF) as a high energy density catholyte was developed. A synergistic approach to the molecular design of tetrathiafulvalene (TTF) was applied, with the incorporation of polyethylene glycol (PEG) chains, which enhance its solubility in organic carbonate electrolytes, and a perfluoro (PerF) group to increase its redox potential. When paired with a lithium metal anode, the two‐electron‐active (PEG3/PerF)‐TTF catholyte produced a cell voltage of 3.56 V for the first redox process and 3.92 V for the second redox process. In cyclic voltammetry and flow cell tests, the redox chemistry exhibited excellent cycling stability. The Li|(PEG3/PerF)‐TTF batteries, with concentrations of 0.1 M and 0.5 M, demonstrated capacity retention rates of ~94 % (99.87 % per cycle, 97.52 % per day) and 90 % (99.93 % per cycle, 99.16 % per day), and the average Coulombic efficiencies of 99.38 % and 98.35 %, respectively. The flow cell achieved a high power density of 129 mW/cm2. Furthermore, owing to the high redox potential and solubility of (PEG3/PerF)‐TTF, the flow cell attained a high operational energy density of 72 Wh/L (100 Wh/L theoretical). A 0.75 M flow cell exhibited an even higher operational energy density of 96 Wh/L (150 Wh/L theoretical). [ABSTRACT FROM AUTHOR]

The chiral-induced spin selectivity (CISS) effect offers promising prospects for spintronics, yet designing chiral materials that enable efficient spin-polarized electron transport remains challenging. Here, we report the utility of covalent organic frameworks (COFs) in manipulating electron spin for spin-dependent catalysis via CISS. This enables us to design and synthesize three three-dimensional chiral COFs (CCOFs) with tunable electroactivity and spin-electron conductivity through imine condensations of enantiopure 1,1′-binaphthol-derived tetraaldehyde and tetraamines derived from 1,4-benzenediamine, pyrene, or tetrathiafulvalene skeletons. The CISS effect of CCOFs is verified by magnetic conductive atomic force microscopy. Compared with their achiral analogs, these CCOFs serve as efficient spin filters, reducing the overpotential of oxygen evolution and improving the Tafel slope. Particularly, the diarylamine-based CCOF showed a low overpotential of 430 mV (vs reversible hydrogen electrode) at 10 mA cm−2 with long-term stability comparable to the commercial RuO2. This enhanced spin-dependent OER activity stems from its excellent redox-activity, good electron conductivity and effective suppression effect on the formation of H2O2 byproducts. [ABSTRACT FROM AUTHOR]

Calix[4]arenes and calix[4]resorcinarenes are well‐known macrocyclic hosts that can be tailored to bind guests of very different natures, including anions, cations, and various neutral molecules. The molecular architectures of the hosts can be altered in many ways: by attaching polar or hydrophilic groups, extending inner cavities with enlarged aromatic side walls, and adding H‐bonding sites to promote the formation of molecular capsules. The attachment of different types of redox‐active moieties renders calix[4]arene and calix[4]resorcinarene derivatives electrochemically active, enabling them to either control the guest‐binding properties of the receptors or be used as electrochemical sensors. This review will focus on calix[4]arene and calix[4]resorcinarene macrocyclic hosts with appended redox‐active groups, such as ferrocene, tetrathiafulvalene, and quinone. We will discuss molecular receptors that can serve as redox sensors for cations or electron‐deficient molecules or can bind and release their guests controlled by redox or electrochemical stimuli. [ABSTRACT FROM AUTHOR]

This study explores the remarkable properties of liquescent open‐shell ionic molecular systems, emphasizing the magnetic and photophysical characteristics arising from their associated structures in the condensed state under various conditions. Well‐investigated open‐shell molecules, namely, phenothiazine, dihydrophenazine, and tetrathiafulvalene radical cations, and bis(malononitriledithiolato)nickel(III) anionic complexes were examined, and the concept of liquescent open‐shell ionic molecular systems was devised. Transformations in their associated structures are induced by external stimuli, resulting in significant variations in their physical properties. These experimental findings open new avenues for exploring and applying stimuli‐responsive molecule‐based materials. [ABSTRACT FROM AUTHOR]

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 exploitation of high performance redox-active substances is critically important for the development of non-aqueous redox flow batteries. Herein, three tetrathiofulvalene (TTF) derivatives with different substitution groups, namely TTF diethyl ester (TTFDE), TTF tetramethyl ester (TTFTM), and TTF tetraethyl ester (TTFTE), are prepared and their energy storage properties are evaluated. It has been found that the redox potential and solubility of these TTF derivatives in conventional carbonate electrolytes increases with the number of ester groups. The battery with a catholyte of 0.2 mol L-1 of TTFTE delivers a specific capacity of more than 10 Ah L-1 at the current density of 0.5 C with two discharge voltage platforms locating at as high as 3.85 and 3.60 V vs. Li/Li+. Its capacity retention can be improved from 2.34 Ah L-1 to 3.60 Ah L-1 after 100 cycles by the use of an anion exchange membrane to block the crossover of TTF species. The excellent cycling stability of the TIF esters is supported by their well-delocalized electrons, as revealed by the density function theory calculations. Therefore, the introduction of more and larger electron-withdrawing groups is a promising strategy to simultaneously increase the redox-potential and solubility of redox-active materials for non-aqueous redox flow batteries. [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]

Modification of hole transporting layers (HTLs) to reduce the interface defects is an important strategy to promote hole extraction and suppress charge recombination for Sb2(S,Se)3 (antimony selenosulfide) solar cells. Herein, a simple doping method with the tetrathiafulvalene derivatives (MeS‐TTF and Cyano‐TTF) is developed to reduce the dangling bonding defects on the surface of Sb2(S,Se)3 films and improve the photovoltaic performances of Sb2(S,Se)3 solar cells. The studies show that the tetrathiafulvalene derivatives can effectively passivate the ionic defects through the chelation mechanism with Sb atoms and suppress the nonradiative recombination. Meanwhile, the MeS‐TTF dopant can also enhance the hole mobility of HTLs and improve the hole transport. The results indicate that the MeS‐TTF can achieve the dual function of interface defect passivation and hole mobility improvement. As a result of the dual‐function dopant, a significant increase in efficiency from 7.73% to 8.45% can be obtained. The outcomes of this study highlight that this dual‐function doping strategy is an effective method to passivate the interface defects and enhance the hole mobility for the excellent photovoltaic performances of Sb2(S,Se)3 solar cells. [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]

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]

Membranekess enzymatic biofuel cells (EBFCs) have the potential to be used in biocompatible devices, such as implantable or wearable devices. However, they face challenges due to low reaction surface area and high resistance attributed to large particle size and protein composition of enzyme catalysts used. In this study, to improve the performance of membraneless EBFCs, three-dimensional graphite felt (3D-GF) electrode was utilized. The 3D-GF electrode has high electrical conductivity and large surface area, allowing the large loading of catalytic components and increasing the reactivity of redox reaction required for EBFC operation. Membraneless EBFC using the 3D-GF electrode is prepared with anodic catalyst including glucose oxidase (GOx) and tetrathiafulvalene mediator, and cathodic catalyst of horseradish peroxidase and GOx. The outermost layer of 3D-GF electrode is coated with gelatin crosslinked by glutar-aldehyde to prevent leaching of components of catalysts. According to evaluations, both anodic and cathodic catalysts are evenly distributed on 3D-GF electrode, and anodic and cathodic currents of 103.5 and 68.7 µA at 0.3 V vs. Ag/AgCl are measured. Additionally, EBFCs using the optimized electrodes demonstrate high power output of 82 µW in a small cell kit size of 1.5×1.5×1.5 cm3, with excellent design flexibility. [ABSTRACT FROM AUTHOR]

Reagentless electrochemical glucose biosensors were developed and investigated. A graphite rod (GR) electrode modified with electrochemically synthesized dendritic gold nanostructures (DGNs) and redox mediators (Med) such as ferrocenecarboxylic acid (FCA), 1,10-phenathroline-5,6-dione (PD), N,N,N′,N′-tetramethylbenzidine (TMB) or tetrathiafulvalene (TTF) in combination with glucose oxidase (GOx) (GR/DGNs/FCA/GOx, GR/DGNs/PD/GOx, GR/DGNs/TMB/GOx, or GR/DGNs/TTF/GOx) were developed and electrochemically investigated. A biosensor based on threefold-layer-by-layer-deposited PD and GOx (GR/DGNs/(PD/GOx)3) was found to be the most suitable for the determination of glucose. To improve the performance of the developed biosensor, the surface of the GR/DGNs/(PD/GOx)3 electrode was modified with polypyrrole (Ppy) for 5 h. A glucose biosensor based on a GR/DGNs/(PD/GOx)3/Ppy(5 h) electrode was characterized using a wide linear dynamic range of up to 39.0 mmol L−1 of glucose, sensitivity of 3.03 µA mM−1 cm−2, limit of detection of 0.683 mmol L−1, and repeatability of 9.03% for a 29.4 mmol L−1 glucose concentration. The Ppy-based glucose biosensor was characterized by a good storage stability (τ1/2 = 9.0 days). Additionally, the performance of the developed biosensor in blood serum was investigated. [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]

Ordered interlayer stacking is intrinsic in two-dimensional covalent organic frameworks (2D COFs) and has strong implications on COF's optoelectronic properties. Reversible interlayer sliding, corresponding to shearing of 2D layers along their basal plane, is an appealing dynamic control of both structures and properties, yet it remains unexplored in the 2D COF field. Herein, we demonstrate that the reversible interlayer sliding can be realized in an imine-linked tetrathiafulvalene (TTF)-based COF TTF-DMTA. The solvent treatment induces crystalline phase changes between the proposed staircase-like sql net structure and a slightly slipped eclipsed sql net structure. The solvation-induced crystallinity changes correlate well with reversible spectroscopic and electrical conductivity changes as demonstrated in oriented COF thin films. In contrast, no reversible switching is observed in a related TTF-TA COF, which differs from TTF-DMTA in terms of the absence of methoxy groups on the phenylene linkers. This work represents the first 2D COF example of which eclipsed and staircase-like aggregated states are interchangeably accessed via interlayer sliding, an uncharted structural feature that may enable applications such as chemiresistive sensors.

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]

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]

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]

Recently, the combined application of synergistic therapies for photodynamic antimicrobial chemotherapy has become important to obtain more efficient results. The synergism between two sensitizers, rose bengal (RB) and chlorin e6 (Ce6), excited by two different methods, was evaluated as a novel approach to both photodynamic and sonodynamic therapy against methicillin-resistant Staphylococcus aureus. The sonostability and singlet oxygen generation (with 1,3-diphenylisobenzofuran for RB and tetrathiafulvalene for Ce6) were measured under sonication (1 MHz, 3 W) using a spectrophotometer. RB and Ce6 remained stable during sonication. RB was a more efficient sonosensitizer than Ce6. The dual synergism between RB and Ce6 was noticed, achieving a >3 log reduction for molar ratios RB:Ce6 of 1:1 and 1:3, while, alone, the sensitizers excited with ultrasound and light, respectively, achieved only ca. a 1 log reduction. [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]

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]

Tetrathiafulvalene (TTF) exhibits two reversible oxidation steps and is used as a novel multi‐electron catholyte for nonaqueous organic redox flow batteries. To increase solubility in polar organic solvents, TTF derivatives with polar side chains are synthesized. 4‐Methoxymethyltetrathiafulvalene emerges as a promising two‐electron catholyte because it is a liquid at room temperature and miscible with acetonitrile. Bulk‐electrolysis experiments and UV‐vis‐NIR absorption spectroscopy reveal excellent cycling stability for the first and second electrochemical oxidations. In the doubly oxidized state, the TTF derivatives show a reversible about 1 % loss of the state of charge per day, due to extrinsic effects. In a symmetric redox flow battery, 4‐methoxymethyltetrathiafulvalene shows a volumetric capacity loss of only 0.2 % per cycle with a Coulombic efficiency (CE) of 99.6 %. In an asymmetric redox flow battery with a pyromellitic diimide as two‐electron anolyte, the capacity loss is 0.8 % per cycle, with CE>99 % in each cycle. [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]

The article titled "Front Cover: Diindeno-Fused Corannulene-Extended Tetrathiafulvalenes" in the journal ChemPhotoChem discusses the sequential one-electron oxidations of corannulene-extended tetrathiafulvalene and the resulting color changes. The dication of this compound exhibits some diradicaloid character, as evidenced by the presence of four favorable Clar sextets in the diradicaloid resonance structure. The article provides more detailed information on this topic and can be accessed through the DOI 10.1002/cptc.202400122. [Extracted from the article]

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]

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]

It is a challenge to control the threshold voltage (defined as the voltage at which the current density increases sharply in the direction of forward bias), one of the basic parameters that define a molecular diode. The problem is that strong Fermi‐level pinning of molecular frontier orbitals and the changes in the electronic structure are often overshadowed by the changes in the supramolecular structure. A chemical control approach is proposed to shift the effective threshold voltage of a series of molecular diodes composed of self‐assembled monolayers (SAMs) of π‐extended tetrathiafulvalene (exTTF) derivatives. The highest occupied molecular orbital of the molecules can be tuned by ≈0.6 eV (maximum) with the minimum changes in the supramolecular structure of the SAMs by introducing chlorine atoms or amino substitutional groups into the exTTF moieties. To the best of the authors' knowledge, this is the first paper that reports that the threshold voltage of the exTTF‐based diode can be modulated from 0.65 to 1.70 V. In addition, it is shown that these four molecular diodes can operate as half‐wave rectifiers with the threshold voltage at positive direct current output ranging from 1.63 to 2.40 V, with the input voltage being 3.0 V at 500 Hz. [ABSTRACT FROM AUTHOR]