Cyclodextrin-based rotaxanes for polymer materials: challenge on simultaneous realization of inexpensive production and defined structures

• Yosuke Akae

Beilstein J. Org. Chem. 2024, 20, 3026–3049, doi:10.3762/bjoc.20.252

• tetrathiafulvalene (TTF) and a triazole ring (Figure 7A) [61]. CD was located around the TTF moiety under neutral conditions; however, it moved to the triazole ring, following TTF oxidization. Meanwhile, the structural control by exploring the solvent polarity was reported by Harada and co-workers using the α-CD

Switchable molecular tweezers: design and applications

• Pablo Msellem,
• Maksym Dekthiarenko,
• Nihal Hadj Seyd and
• Guillaume Vives

Beilstein J. Org. Chem. 2024, 20, 504–539, doi:10.3762/bjoc.20.45

• acridinium is that it can undergo the addition of a nucleophile like HO− or RO− forming an acridane derivative having non-planar geometry and different electronic properties. Triphenylene tweezers 6 are able to intercalate planar electron-rich guest molecules like TTF and pyrene. Upon the addition of a

• tetrathiafulvalene (TTF) arms, adopting a 1,3-alternate conformation by default with two cavities for binding electron-poor guests between the TTFs (Figure 18). The authors demonstrated complexation with 1,3,5-trinitrobenzene and other electron-poor guests such as TCNQ. The N–H protons of the pyrrole subunits can

• -conformation calix[4]pyrrole and the electron-donating nature of TTFs allow the complexation of electron-poor C60 guests [71]. A 2:1 complexation of C60 by TTF-functionalized calix[4]pyrrole 33 was observed for the Cl− bound cone conformation with each calix[4]pyrrole entrapping C60 on one side. The complex

Photochromic derivatives of indigo: historical overview of development, challenges and applications

• Gökhan Kaplan,
• Zeynel Seferoğlu and
• Daria V. Berdnikova

Beilstein J. Org. Chem. 2024, 20, 228–242, doi:10.3762/bjoc.20.23

• incorporating redox-active tetrathiafulvalene (TTF) residues (Figure 7), known for their ability to form intramolecular π-dimers upon two-electron oxidation [47]. Thus, upon irradiation of the oxidized molecule 24 with 660 nm light, the thermal half-life of the Z-isomer exhibited a significant increase

Perspectives on push–pull chromophores derived from click-type [2 + 2] cycloaddition–retroelectrocyclization reactions of electron-rich alkynes and electron-deficient alkenes

• Michio Yamada

Beilstein J. Org. Chem. 2024, 20, 125–154, doi:10.3762/bjoc.20.13

• of 102, the rectification property of a compound wherein TTF and DCNQ are linked by a rigid spacer has also been reported [149]. Misra et al. designed and synthesized a series of chromophore molecules 105–112 featuring porphyrin moieties and investigated their photophysical properties. They found

Multi-redox indenofluorene chromophores incorporating dithiafulvene donor and ene/enediyne acceptor units

• Christina Schøttler,
• Kasper Lund-Rasmussen,
• Line Broløs,
• Philip Vinterberg,
• Ema Bazikova,
• Viktor B. R. Pedersen and
• Mogens Brøndsted Nielsen

Beilstein J. Org. Chem. 2024, 20, 59–73, doi:10.3762/bjoc.20.8

• Tetrathiafulvalene (TTF, Figure 1) is a redox-active molecule that has been widely explored in materials chemistry and supramolecular chemistry [1][2][3][4][5][6][7][8]. TTF reversibly undergoes two sequential one-electron oxidations, generating first a radical cation (TTF+•) and subsequently a dication (TTF2

• pyrrole unit to one of the dithiole rings of an IF-TTF, allowing for dimerization of extended TTFs via the nitrogen atom by different linkers [14]. Donor–acceptor chromophores can be obtained by replacing one of the dithiafulvene (DTF) rings of the IF-TTF by an electron acceptor. Cyclic and acyclic

• Supporting Information File 1). We speculate that this degradation is due to the reaction with singlet oxygen generated by the compound as a photosensitizer; indeed, we have recently shown [31] that IF-TTF compounds are reactive towards singlet oxygen at the central fulvene bond but, in contrast, IF-TTFs

Aromatic systems with two and three pyridine-2,6-dicarbazolyl-3,5-dicarbonitrile fragments as electron-transporting organic semiconductors exhibiting long-lived emissions

• Karolis Leitonas,
• Brigita Vigante,
• Dmytro Volyniuk,
• Audrius Bucinskas,
• Pavels Dimitrijevs,
• Sindija Lapcinska,
• Pavel Arsenyan and
• Juozas Vidas Grazulevicius

Beilstein J. Org. Chem. 2023, 19, 1867–1880, doi:10.3762/bjoc.19.139

• NMR spectra. Funding This work was supported by the project of scientific co-operation program between Latvia, Lithuania, and Taiwan, "Synthesis and study of deep-blue TTF fluorescent emitters to exceed theoretical OLED external quantum efficiency reaching 15%" (grant LV-LT-TW/2023) and Research

Thermodynamic and electrochemical study of tailor-made crown ethers for redox-switchable (pseudo)rotaxanes

• Henrik Hupatz,
• Marius Gaedke,
• Hendrik V. Schröder,
• Julia Beerhues,
• Arto Valkonen,
• Fabian Klautzsch,
• Sebastian Müller,
• Felix Witte,
• Kari Rissanen,
• Biprajit Sarkar and
• Christoph A. Schalley

Beilstein J. Org. Chem. 2020, 16, 2576–2588, doi:10.3762/bjoc.16.209

• synthetic molecular machines. Developing switchable and specifically designed crown ethers enables the implementation of function into molecular assemblies. Seven tailor-made redox-active crown ethers incorporating tetrathiafulvalene (TTF) or naphthalene diimide (NDI) as redox-switchable building blocks are

• electrochemical output. For example, crown ethers containing tetrathiafulvalene (TTF) derivatives, which enable two reversible oxidation processes from the neutral to the dicationic state, were applied to sense various cations, e.g., alkali metal ions, Pb2+, and Ba2+ [18][19][20][21]. Furthermore, with the first

• MIMs based on two 24-crown-8 ethers functionalized with TTF TTFC8 [35][36] and exTTFC8 [37] (Figure 1). Several TTFC8-derived molecular assemblies have been studied and provided access to new switching modes [35][36][38] and emergent optoelectronic properties [35][36][39][40], demonstrating the great

Synthesis and properties of tetrathiafulvalenes bearing 6-aryl-1,4-dithiafulvenes

• Aya Yoshimura,
• Hitoshi Kimura,
• Kohei Kagawa,
• Mayuka Yoshioka,
• Toshiki Itou,
• Dhananjayan Vasu,
• Takashi Shirahata,
• Hideki Yorimitsu and
• Yohji Misaki

Beilstein J. Org. Chem. 2020, 16, 974–981, doi:10.3762/bjoc.16.86

• Abstract Novel multistage redox tetrathiafulvalenes (TTFs) bearing 6-aryl-1,4-dithiafulvene moieties were synthesized by palladium-catalyzed direct C–H arylation. In the presence of a catalytic amount of Pd(OAc)2, P(t-Bu3)·HBF4, and an excess of Cs2CO3, the C–H arylation of TTF with several aryl bromides

• (FETs), and positive electrode materials for rechargeable batteries because the TTF moiety has strong electron-donating properties attributed to the formation of stable aromatic 1,3-dithiol-2-ylidenes (1,3-dithiole rings) by one- and two-electron oxidation [1][2][3][4][5][6][7][8][9][10][11][12][13][14

• of 1,3-dithiole rings to aromatic rings appears very appealing since these allow to produce novel multistage redox systems. However, such molecules could formerly not be synthesized by conventional approaches. In 2011, a breakthrough synthesis of arylated TTF derivatives by a palladium-catalyzed

Tetrathiafulvalene – a redox-switchable building block to control motion in mechanically interlocked molecules

• Hendrik V. Schröder and
• Christoph A. Schalley

Beilstein J. Org. Chem. 2018, 14, 2163–2185, doi:10.3762/bjoc.14.190

• contemporary research challenge. Tetrathiafulvalenes (TTFs) are one of the most versatile and widely used molecular redox switches to generate and control molecular motion. TTF can easily be implemented as functional unit into molecular and supramolecular structures and can be reversibly oxidized to a stable

• radical cation or dication. For over 20 years, TTFs have been key building blocks for the construction of redox-switchable mechanically interlocked molecules (MIMs) and their electrochemical operation has been thoroughly investigated. In this review, we provide an introduction into the field of TTF-based

• MIMs and their applications. A brief historical overview and a selection of important examples from the past until now are given. Furthermore, we will highlight our latest research on TTF-based rotaxanes. Keywords: artificial molecular machines; mechanically interlocked molecules; molecular switches

Protonated paramagnetic redox forms of di-o-quinone bridged with p-phenylene-extended TTF: A EPR spectroscopy study

• Nikolay O. Chalkov,
• Vladimir K. Cherkasov,
• Gleb A. Abakumov,
• Andrey G. Starikov and
• Viacheslav A. Kuropatov

Beilstein J. Org. Chem. 2016, 12, 2450–2456, doi:10.3762/bjoc.12.238

• ; EPR spectroscopy; extended tetrathiafulvalene; protonated semiquinone; Introduction The main idea that led to the creation of the system constructed of two o-quinone terminal moieties bridged with annulated extended tetrathiafulvalene (TTF) insertion, was an attempt to explore acceptor–donor–acceptor

• (A–D–A) systems as ligands [1]. A linear planar skeleton of the molecule with coordinating sites placed at the termini allows the construction of ordered structures using metal ions as nodes [2]. The insertion of p-phenylene in the TTF core is of special interest because it can act as a switch which

• distributions in (1·)H and (1·)H3 and the relatively high values of coupling constants with the protons in the EPR spectrum reveal that the p-phenylene-extended TTF bridge provides an effective electronic communication throughout the whole molecule. Obviously, the symmetry of the electron-density delocalization

Urethane tetrathiafulvalene derivatives: synthesis, self-assembly and electrochemical properties

• Xiang Sun,
• Guoqiao Lai,
• Zhifang Li,
• Yuwen Ma,
• Xiao Yuan,
• Yongjia Shen and
• Chengyun Wang

Beilstein J. Org. Chem. 2015, 11, 2343–2349, doi:10.3762/bjoc.11.255

• Technology of Ministry of Education, Hangzhou Normal University, Hangzhou 310012, China 10.3762/bjoc.11.255 Abstract This paper reports the self-assembly of two new tetrathiafulvalene (TTF) derivatives that contain one or two urethane groups. The formation of nanoribbons was evidenced by scanning electron

• driving forces for self-assembly of TTF derivatives were mainly hydrogen bond interactions and π–π stacking interactions. The electronic conductivity of the T1 and T2 films was tested by a four-probe method. Keywords: hydrogen bond; nanoribbon; self-assembly; tetrathiafulvalene; urethane; Introduction

• intermolecular interactions in molecular self-assembly systems. Therefore, molecules containing urea, amide and other similar groups have been investigated because these molecules can easily generate intermolecular hydrogen bonds [7][8][9]. Tetrathiafulvalene (TTF) derivatives have been widely investigated in

Supramolecular chemistry: from aromatic foldamers to solution-phase supramolecular organic frameworks

• Zhan-Ting Li

Beilstein J. Org. Chem. 2015, 11, 2057–2071, doi:10.3762/bjoc.11.222

• sulfur-containing molecules and since the early 1990s, tetrathiafulvalene (TTF) supramolecular chemistry. Before I went to Odense, the group had developed a very useful method of in situ generation of TTF thiolate anion from cyanoethylated precursors, which greatly simplifies the modification of the TTF

• ]catenane 6c with the tetracationic cyclophane holding one of the peripheral benzene rings [14]. The TTF unit in 6a and 6b adopted a stable cis or trans configuration, although typically the two configurations easily isomerize into each other in solution. Macrocycle 3 is a brown solid due to the existence

• of the TTF unit. Catenanes 6a and 6b are blue as a result of the charge-transfer complex between the TTF and bipyridinium units, whereas catenane 6c is orange, which is attributed to the charge-transfer complex between the dioxybenzene and bipyridinium units. Impressively, the three catenanes could

[2.2]Paracyclophane derivatives containing tetrathiafulvalene moieties

• Laura G. Sarbu,
• Lucian G. Bahrin,
• Peter G. Jones,
• Lucian M. Birsa and
• Henning Hopf

Beilstein J. Org. Chem. 2015, 11, 1917–1921, doi:10.3762/bjoc.11.207

• -dithiolium salts; [2.2]paracyclophane; regioselective bromination; stereoisomers; tetrathiafulvalenes; Introduction Tetrathiafulvalene (TTF) and its derivatives have been extensively studied with respect to their applications as organic metals and superconductors [1][2]. These properties are a consequence

• of the π-donor properties of TTF and of its important intermolecular interactions in the solid state through extended π-orbitals. The design of new tetrathiafulvalene derivatives has targeted those systems where the intermolecular interactions between planar molecules are more effective and the solid

Polythiophene and oligothiophene systems modified by TTF electroactive units for organic electronics

• Alexander L. Kanibolotsky,
• Neil J. Findlay and
• Peter J. Skabara

Beilstein J. Org. Chem. 2015, 11, 1749–1766, doi:10.3762/bjoc.11.191

• Abstract The aim of this review is to give an update on current progress in the synthesis, properties and applications of thiophene-based conjugated systems bearing tetrathiafulvalene (TTF) units. We focus mostly on the synthesis of poly- and oligothiophenes with TTF moieties fused to the thiophene units

• in organic field effect transistors and solar cells. Keywords: donor; oligothiophene; organic electronics; polythiophene; semiconductor; tetrathiafulvalene; Introduction Sulfur-rich π-functional systems are important building blocks in materials chemistry. Among them, tetrathiafulvalene (TTF

• units into a conjugated network is a standard way to narrow the HOMO/LUMO band gap and examples of such units include dioxopyrrolopyrrole (DPP) [17][18][19], benzodifuranone [20] and boron-dipyrromethene (BODIPY) [21][22]. As a different class of electroactive materials, TTF derivatives are well-known

Star-shaped tetrathiafulvalene oligomers towards the construction of conducting supramolecular assembly

• Masahiko Iyoda and
• Masashi Hasegawa

Beilstein J. Org. Chem. 2015, 11, 1596–1613, doi:10.3762/bjoc.11.175

• 10.3762/bjoc.11.175 Abstract The construction of redox-active supramolecular assemblies based on star-shaped and radially expanded tetrathiafulvalene (TTF) oligomers with divergent and extended conjugation is summarized. Star-shaped TTF oligomers easily self-aggregate with a nanophase separation to

• produce supramolecular structures, and their TTF units stack face-to-face to form columnar structures using the fastener effect. Based on redox-active self-organizing supramolecular structures, conducting nanoobjects are constructed by doping of TTF oligomers with oxidants after the formation of such

• nanostructures. Although radical cations derived from TTF oligomers strongly interact in solution to produce a mixed-valence dimer and π-dimer, it seems to be difficult to produce nanoobjects of radical cations different from those of neutral TTF oligomers. In some cases, however, radical cations form

Synthesis of racemic and chiral BEDT-TTF derivatives possessing hydroxy groups and their achiral and chiral charge transfer complexes

• Sara J. Krivickas,
• Chiho Hashimoto,
• Junya Yoshida,
• Akira Ueda,
• Kazuyuki Takahashi,
• John D. Wallis and
• Hatsumi Mori

Beilstein J. Org. Chem. 2015, 11, 1561–1569, doi:10.3762/bjoc.11.172

• chiral crystals. Racemic and enantiopure bis(ethylenedithio)tetrathiafulvalene (BEDT-TTF) derivatives possessing hydroxymethyl groups as the source of hydrogen bonds were designed. The novel racemic trans-vic-(hydroxymethyl)(methyl)-BEDT-TTF 1, and racemic and enantiopure trans-vic-bis(hydroxymethyl

• )-BEDT-TTF 2 were synthesized. Moreover, the preparations, crystal structure analyses, and electrical resistivity measurements of the novel achiral charge transfer salt θ21-[(S,S)-2]3[(R,R)-2]3(ClO4)2 and the chiral salt α’-[(R,R)-2]ClO4(H2O) were carried out. In the former θ21-[(S,S)-2]3[(R,R)-2]3(ClO4

• chirality, but also the introduced intermolecular hydrogen bonds involving the hydroxymethyl groups, perchlorate anion, and the included solvent H2O. Keywords: BEDT-TTF; chiral molecular crystal; hydrogen bonding; hydroxy group; molecular conductors; Introduction The chiral crystals without an inversion

Tetrathiafulvalene chemistry

• Peter J. Skabara and
• Marc Sallé

Beilstein J. Org. Chem. 2015, 11, 1528–1529, doi:10.3762/bjoc.11.167

• Peter J. Skabara Marc Salle WestCHEM, Department of Pure and Applied Chemistry, University of Strathclyde, Glasgow G1 1XL, United Kingdom MOLTECH-Anjou, Université d’Angers, UMR CNRS 6200, 2 Bd Lavoisier, 49045 Angers Cedex, France 10.3762/bjoc.11.167 Keywords: tetrathiafulvalene; TTF

• ; Tetrathiafulvalene (TTF) is a fascinating system: it is quite rare to find a synthetic molecule endowed with such a simple architecture that is capable of concentrating intense interest from various communities of chemists! This modest-sized molecule which consists of only 14 atoms, was synthesized in the early

• salts (organic metals); the topic of organic conductors remains a very active area of research, attested by thousands of papers from chemists and physicists interested in the transport properties of TTF-based materials [4][5]; ii) this non-aromatic 14 π-electron system is readily oxidized through a

Tetrathiafulvalene-based azine ligands for anion and metal cation coordination

• Awatef Ayadi,
• Aziz El Alamy,
• Olivier Alévêque,
• Magali Allain,
• Nabil Zouari,
• Mohammed Bouachrine and
• Abdelkrim El-Ghayoury

Beilstein J. Org. Chem. 2015, 11, 1379–1391, doi:10.3762/bjoc.11.149

• prepared electroactive rhenium complex the TTF is neutral and the rhenium cation is hexacoordinated. The electrochemical behavior of the three compounds indicates that they are promising for the construction of crystalline radical cation salts. Keywords: azine ligand; fluoride sensing; rhenium

• ; tetrathiafulvalene; X-ray; Introduction Tetrathiafulvalene (TTF) is known to have excellent electron-donating properties resulting in stable radical cation (TTF•+) and dication (TTF2+) species from two sequential and reversible oxidation processes. The huge interest in the synthesis of TTF and its very numerous

• derivatives [1] has been initiated by the high electrical conductivity discovered in a chloride salt of TTF [2] and metallic behavior in the charge-transfer complex with 7,7,8,8-tetracyano-p-quinodimethane (TCNQ) [3]. These systems have played a major role for the preparation of molecular materials designed

Thiazole-induced rigidification in substituted dithieno-tetrathiafulvalene: the effect of planarisation on charge transport properties

• Rupert G. D. Taylor,
• Joseph Cameron,
• Iain A. Wright,
• Neil Thomson,
• Olena Avramchenko,
• Alexander L. Kanibolotsky,
• Anto R. Inigo,
• Tell Tuttle and
• Peter J. Skabara

Beilstein J. Org. Chem. 2015, 11, 1148–1154, doi:10.3762/bjoc.11.129

• Physical-Organic Chemistry and Coal Chemistry, 02160 Kyiv, Ukraine 10.3762/bjoc.11.129 Abstract Two novel tetrathiafulvalene (TTF) containing compounds 1 and 2 have been synthesised via a four-fold Stille coupling between a tetrabromo-dithienoTTF 5 and stannylated thiophene 6 or thiazole 4. The optical

• demonstrated that the substitution of thiophene units for thiazoles was found to increase the observed charge transport, which is attributed to induced planarity through S–N interactions of adjacent thiazole nitrogen atoms and TTF sulfur atoms and better packing in the bulk. Keywords: non-covalent

• interactions; organic field effect transistor (OFET); organic semiconductors; tetrathiafulvalene; thiazole; Introduction The TTF moiety has received much attention in the field of organic electronics owing to its reliable redox behaviour [1], good charge transport properties [2] and scope for

New tris- and pentakis-fused donors containing extended tetrathiafulvalenes: New positive electrode materials for rechargeable batteries

• Shintaro Iwamoto,
• Yuu Inatomi,
• Daisuke Ogi,
• Satoshi Shibayama,
• Yukiko Murakami,
• Minami Kato,
• Kazuyuki Takahashi,
• Kazuyoshi Tanaka,
• Nobuhiko Hojo and
• Yohji Misaki

Beilstein J. Org. Chem. 2015, 11, 1136–1147, doi:10.3762/bjoc.11.128

• Strategy Initiative for Catalysts and Batteries (ESICB), Kyoto University, Katsura, Kyoto 615-8520, Japan 10.3762/bjoc.11.128 Abstract Derivatives of tris-fused TTF extended with two ethanediylidenes (5), tris- and pentakis-fused TTFs extended with two thiophene-2,5-diylidenes (6–9) were successfully

• –680 mAh g−1. The discharge capacities after 40 cycles were 64–86% of the initial discharge capacities. Keywords: cyclic voltammetry; positive electrode materials; rechargeable battery; redox; tetrathiafulvalene; Introduction Tetrathiafulvalene (TTF, 1a) and its analogues have attracted much

• attention as potential components for organic functional materials as well as multi-electron redox systems [1][2][3][4][5]. Fused TTF oligomers [5] are of considerable interest as multi-electron redox systems, because the TTF units strongly interact with each other. For example, a bis-fused TTF, 2,5-bis(1,3

Advances in the synthesis of functionalised pyrrolotetrathiafulvalenes

• Luke J. O’Driscoll,
• Sissel S. Andersen,
• Marta V. Solano,
• Dan Bendixen,
• Morten Jensen,
• Troels Duedal,
• Jess Lycoops,
• Cornelia van der Pol,
• Rebecca E. Sørensen,
• Karina R. Larsen,
• Kenneth Myntman,
• Christian Henriksen,
• Stinne W. Hansen and
• Jan O. Jeppesen

Beilstein J. Org. Chem. 2015, 11, 1112–1122, doi:10.3762/bjoc.11.125

• Southern Denmark, Campusvej 55, DK-5230, Odense M, Denmark 10.3762/bjoc.11.125 Abstract The electron-donor and unique redox properties of the tetrathiafulvalene (TTF, 1) moiety have led to diverse applications in many areas of chemistry. Monopyrrolotetrathiafulvalenes (MPTTFs, 4) and

• to the N-arylation of MPTTFs and BPTTFs using a variety of aryl halides. Keywords: heterocycles; protecting groups; sulfur chemistry; tetrathiafulvalene; Ullman coupling; Introduction Tetrathiafulvalene (TTF) derivatives are of considerable interest in the fields of supramolecular chemistry and

• molecular machines [1][2][3][4][5], molecular and organic electronics [5][6][7], chemosensors [1][8][9][10][11], coordination chemistry [12][13][14], catalysis [15] and beyond [16][17][18][19][20][21]. This owes much to the strong electron-donor character of the TTF moiety and its derivatives, which have

Regioselective synthesis of chiral dimethyl-bis(ethylenedithio)tetrathiafulvalene sulfones

• Flavia Pop and
• Narcis Avarvari

Beilstein J. Org. Chem. 2015, 11, 1105–1111, doi:10.3762/bjoc.11.124

• aerial oxidation of the chiral dithiolates generated from the propionitrile-protected precursors. Both enantiomers crystallize in the orthorhombic chiral space group P212121. They show a boat-type conformation of the TTF moiety, a rather rigid dithiin sulfone ring and the methyl groups in a bisequatorial

• conformation. Cyclic voltammetry measurements indicate fully reversible oxidation in radical cation and dication species. Keywords: chirality; crystal structures; molecular materials; sulfones; tetrathiafulvalenes; Introduction Chiral tetrathiafulvalene (TTF) derivatives have been addressed for the first

• time in the middle of 80s by Dunitz and Wallis through the synthesis of the (S,S,S,S)-enantiomer of tetramethyl-bis(ethylenedithio)tetrathiafulvalene (TM-BEDT-TTF) (Scheme 1) [1], thus opening opportunities towards the preparation of chiral molecular conductors [2]. Since then a large number of chiral

Single-molecule conductance of a chemically modified, π-extended tetrathiafulvalene and its charge-transfer complex with F₄TCNQ

• Raúl García,
• M. Ángeles Herranz,
• Edmund Leary,
• M. Teresa González,
• Gabino Rubio Bollinger,
• Marius Bürkle,
• Linda A. Zotti,
• Yoshihiro Asai,
• Fabian Pauly,
• Juan Carlos Cuevas,
• Nicolás Agraït and
• Nazario Martín

Beilstein J. Org. Chem. 2015, 11, 1068–1078, doi:10.3762/bjoc.11.120

• viologen [5][6], aniline [7][8], thiophene [9], anthraquinone [10] and ferrocene [11] have been previously studied. However, a particularly suitable redox-active molecule for molecular electronics is the well-known electron donor tetrathiafulvalene (TTF) molecule. Pristine TTF, as well as the

• tetraselenafulvalene analogue (TSF), have been previously reported. In this study, the authors hypothesized that in the Au–TTF–Au junctions, the molecule is connected to the electrodes in a face-to-face overlapping configuration [12]. In contrast, since the first report on a suitably functionalized TTF as a molecular

• wire using two thioacetate anchoring groups [13], most of the TTF derivatives synthesized for this purpose have been functionalized with sulfur atoms as alligator clips. These belong either to a fused ring on the TTF [14], or to a chain covalently connected to the TTF core bearing a thiol group at the

A hybrid electron donor comprising cyclopentadithiophene and dithiafulvenyl for dye-sensitized solar cells

• Gleb Sorohhov,
• Chenyi Yi,
• Michael Grätzel,
• Silvio Decurtins and
• Shi-Xia Liu

Beilstein J. Org. Chem. 2015, 11, 1052–1059, doi:10.3762/bjoc.11.118

• ][8] have been used in the construction of photosensitizers. Not surprisingly, tetrathiafulvalene (TTF), as a strong π-electron donor, has been incorporated into different D–π–A systems for numerous potential applications [9][10][11][12][13][14]. However, TTF-sensitized solar cells have rarely been

• explored [15][16][17], mainly due to the high-lying HOMO energy levels leading to a thermodynamically unfavorable dye regeneration. To overcome this problem, we recently applied a Schiff-base reaction to obtain a rigid and planar quinoxaline-fused TTF-based dye that shows an intense optical ICT absorption

• over a wide spectral range and a substantially stabilized HOMO, leading to a power conversion efficiency of ca. 6.5% [17]. This example represents the currently best performance for TTF-sensitized solar cells. An alternative approach is based on dithiafulvene (DTF), which from a structural point of

Donor–acceptor type co-crystals of arylthio-substituted tetrathiafulvalenes and fullerenes

• Xiaofeng Lu,
• Jibin Sun,
• Shangxi Zhang,
• Longfei Ma,
• Lei Liu,
• Hui Qi,
• Yongliang Shao and
• Xiangfeng Shao

Beilstein J. Org. Chem. 2015, 11, 1043–1051, doi:10.3762/bjoc.11.117

• co-crystals of fullerene (as the acceptor) and arylthio-substituted tetrathiafulvalene derivatives (Ar-S-TTF, as the donor) were prepared and their structural features were thoroughly investigated. The formation of co-crystals relies on the flexibility of Ar-S-TTF and the size matches between Ar-S

• -TTF and fullerene. Regarding their compositions, the studied co-crystals can be divided into two types, where types I and II have donor:acceptor ratios of 1:1 and 1:2, respectively. Multiple intermolecular interactions are observed between the donor and acceptor, which act to stabilize the structures

• of the resulting co-crystals. In the type I co-crystals, the fullerene molecule is surrounded by four Ar-S-TTF molecules, that is, two Ar-S-TTF molecules form a sandwich structure with one fullerene molecule and the other two Ar-S-TTF molecules interact with the fullerene molecule along their lateral