Organic electron transport materials

• Joseph Cameron and
• Peter J. Skabara

Beilstein J. Org. Chem. 2024, 20, 672–674, doi:10.3762/bjoc.20.60

• Joseph Cameron Peter J. Skabara School of Chemistry, University of Glasgow, University Avenue, Glasgow, G12 8QQ, UK 10.3762/bjoc.20.60 Keywords: acceptors; electron transport material; electron-deficient; n-type; organic semiconductors; There has been much interest in developing electron

• materials. One of the potential benefits of organic semiconductors is the ability to use solution-processing techniques, which are more sustainable than thermal evaporation which is wasteful and requires high vacuum and temperature. Moreover, organic electron transport layers do not typically need treatment

Synthesis of π-conjugated polycyclic compounds by late-stage extrusion of chalcogen fragments

• Aissam Okba,
• Pablo Simón Marqués,
• Kyohei Matsuo,
• Naoki Aratani,
• Hiroko Yamada,
• Gwénaël Rapenne and
• Claire Kammerer

Beilstein J. Org. Chem. 2024, 20, 287–305, doi:10.3762/bjoc.20.30

• this situation. Acenes are a class of aromatic compounds composed of linearly fused benzene rings, which can be regarded as the narrowest graphene nanoribbons. They are highly promising p-type organic semiconductors, but suffer from insolubility and instability leading to dimerization and/or

• step in the fabrication of devices. Notably, the use of heteropines as soluble precursors allowed to expand the “precursor approach” to new families of organic semiconductors, such as PBIs and triphenylenes. It is important to mention here that, depending on the nature of the soluble heteropine

Beyond n-dopants for organic semiconductors: use of bibenzo[d]imidazoles in UV-promoted dehalogenation reactions of organic halides

• Kan Tang,
• Megan R. Brown,
• Chad Risko,
• Melissa K. Gish,
• Garry Rumbles,
• Phuc H. Pham,
• Oana R. Luca,
• Stephen Barlow and
• Seth R. Marder

Beilstein J. Org. Chem. 2023, 19, 1912–1922, doi:10.3762/bjoc.19.142

• studies of electrochemically generated reactive species [14][15][16]. More recently, several examples, including (Cyc-DMBI)2 (Y = cyclohexyl) and (N-DMBI)2 (Y = 4-dimethylaminophenyl) have been used as effective n-dopants for organic semiconductors [17][18][19][20][21][22][23][24] and redox mediators for

• the electrochemical depolymerization of poly(ethylene terephthalate) [25]. These dimers (D2 = (Y-DMBI)2) undergo reactions with organic semiconductors A to afford two monomeric Y-DMBI+ (D+) cations and two reduced semiconductors, A•−. The effective redox potentials, E(D+/0.5D2), are estimated to be ca

• electropositive metals and may be of use in more elaborate chemical transformations. Mechanism of dark reactions Doping of organic semiconductors by (Y-DMBI)2 dimers [18][39] or by various dimers formed by 18-electron sandwich compounds [18][40][41], as well as redox reactions of other dimers formed by organic

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

Charge carrier transport in perylene-based and pyrene-based columnar liquid crystals

• Alessandro L. Alves,
• Simone V. Bernardino,
• Carlos H. Stadtlober,
• Edivandro Girotto,
• Giliandro Farias,
• Rodney M. do Nascimento,
• Sergio F. Curcio,
• Thiago Cazati,
• Marta E. R. Dotto,
• Juliana Eccher,
• Leonardo N. Furini,
• Hugo Gallardo,
• Harald Bock and
• Ivan H. Bechtold

Beilstein J. Org. Chem. 2023, 19, 1755–1765, doi:10.3762/bjoc.19.128

• -shifted in the film. These results indicate molecular π-stacking aggregation and excimer formation on the films [2]. The PL in film was obtained as a function of temperature (Figure 4). The observed reduction of the PL intensity on heating is expected for organic semiconductors due to self-quenching

Quinoxaline derivatives as attractive electron-transporting materials

• Zeeshan Abid,
• Liaqat Ali,
• Sughra Gulzar,
• Faiza Wahad,
• Raja Shahid Ashraf and
• Christian B. Nielsen

Beilstein J. Org. Chem. 2023, 19, 1694–1712, doi:10.3762/bjoc.19.124

• Organic semiconductors have emerged as a fascinating class of materials with significant implications for numerous scientific disciplines, including electronics, photonics, and energy conversion. These materials, composed of carbon-based molecules or polymers, offer remarkable flexibility, tunability, and

• processability compared to their inorganic counterparts [1][2]. Charge transport in organic semiconductors is a fundamental aspect that governs the performance and functionality of various organic semiconductor devices, such as organic solar cells (OSCs), organic field-effect transistors (OFETs), organic light

Benzoimidazolium-derived dimeric and hydride n-dopants for organic electron-transport materials: impact of substitution on structures, electrochemistry, and reactivity

• Swagat K. Mohapatra,
• Khaled Al Kurdi,
• Samik Jhulki,
• Georgii Bogdanov,
• John Bacsa,
• Maxwell Conte,
• Tatiana V. Timofeeva,
• Seth R. Marder and
• Stephen Barlow

Beilstein J. Org. Chem. 2023, 19, 1651–1663, doi:10.3762/bjoc.19.121

• doping of organic semiconductors can play an important role in tuning the properties of organic semiconductors for a variety of applications [1][2][3][4][5]. The most straightforward n-dopants for doping electron-transporting materials are simple one-electron reductants; however, to be effective for a

• strength and their reactivity with organic semiconductors (SC) does not depend solely on the SC reduction potential, since the first step, at least in many cases, is a hydride transfer rather than an electron transfer [8][9]. Moreover, as well forming the desired semiconductor radical anion SC•−, and the

• oxidized than [RuCp*(1,3,5-Me3C6H3)]2 (−1.09 V) [61] and, like [RuCp*(1,3,5-Me3C6H3)]2, can still be handled in air. Reactivity To compare the reactivity of the new compounds towards relevant organic semiconductors (SC), we have examined the reactions of the 1H derivatives with the solubilized fullerene

Preparation of β-cyclodextrin-based dimers with selectively methylated rims and their use for solubilization of tetracene

• Konstantin Lebedinskiy,
• Volodymyr Lobaz and
• Jindřich Jindřich

Beilstein J. Org. Chem. 2022, 18, 1596–1606, doi:10.3762/bjoc.18.170

• could be expected that the extension of the hydrophobic cavity by the combined methylation and “dimerization” may improve the binding potential towards such substrates even more. Linear polycyclic aromatic hydrocarbons (acenes) and their derivatives are good organic semiconductors and show interesting

Electrochemical and spectroscopic properties of twisted dibenzo[g,p]chrysene derivatives

• Tomoya Imai,
• Ryuhei Akasaka,
• Naruhiro Yoshida,
• Toru Amaya and
• Tetsuo Iwasawa

Beilstein J. Org. Chem. 2022, 18, 963–971, doi:10.3762/bjoc.18.96

• acenes are an interesting class of compounds due to their characteristic structures and conjugation systems [23][24][25]. Dibenzo[g,p]chrysene (DBC), which consists of a twisted naphthalene core with four fused benzene rings (Figure 1a) [26], is a promising framework for serving as organic semiconductors

Introducing a new 7-ring fused diindenone-dithieno[3,2-b:2',3'-d]thiophene unit as a promising component for organic semiconductor materials

• Valentin H. K. Fell,
• Joseph Cameron,
• Alexander L. Kanibolotsky,
• Eman J. Hussien and
• Peter J. Skabara

Beilstein J. Org. Chem. 2022, 18, 944–955, doi:10.3762/bjoc.18.94

• dichloromethane. There are numerous examples of fused, conjugated materials containing a thiophene motif. In a comprehensive and detailed review, Ozturk et al. summarised the chemistry and properties of fused thiophene systems [23], and pointed out their importance in the field of organic semiconductors. Earlier

• been applied in various different molecules, exhibiting outstanding performances in certain applications. The highest hole mobility for organic semiconductors was achieved for thin, crystalline films of 2,7-dioctyl[1]benzothieno[3,2-b][1]-benzothiophene (8), shown in Figure 3, achieving a maximum hole

Post-synthesis from Lewis acid–base interaction: an alternative way to generate light and harvest triplet excitons

• Hengjia Liu and
• Guohua Xie

Beilstein J. Org. Chem. 2022, 18, 825–836, doi:10.3762/bjoc.18.83

• red-shifted with increasing the concentration of the Lewis acid, changing from 440 nm to 520 nm. In order to further explore the doping mechanism of Lewis acid on organic semiconductors, Yurash et al. found that B(C6F5)3 possessed the best doping effect and thus increased the conductivity, compared

Synthesis of bis-spirocyclic derivatives of 3-azabicyclo[3.1.0]hexane via cyclopropene cycloadditions to the stable azomethine ylide derived from Ruhemann's purple

• Alexander S. Filatov,
• Olesya V. Khoroshilova,
• Anna G. Larina,
• Vitali M. Boitsov and
• Alexander V. Stepakov

Beilstein J. Org. Chem. 2022, 18, 769–780, doi:10.3762/bjoc.18.77

• ], anticancer [4], antidiabetic [5], and antibacterial [6] properties. It is also worth noting that spiro compounds have found application in agriculture as fungicides [7], as well as in materials science as organic semiconductors [8]. The 3-azabicyclo[3.1.0]hexane framework is a valuable structural fragment

Synthetic approaches to bowl-shaped π-conjugated sumanene and its congeners

• Shakeel Alvi and
• Rashid Ali

Beilstein J. Org. Chem. 2020, 16, 2212–2259, doi:10.3762/bjoc.16.186

Synthesis of 6,13-difluoropentacene

• Matthias W. Tripp and
• Ulrich Koert

Beilstein J. Org. Chem. 2020, 16, 2136–2140, doi:10.3762/bjoc.16.181

• HOMO–LUMO gap of 6,13-difluoropentacene was determined via UV–vis spectroscopy and compared to other fluorinated pentacenes. Keywords: fluorinated acenes; Friedel–Crafts reaction; ortho-lithiation; synthesis; Introduction Pentacenes are a prototype in the field of organic semiconductors due to their

Heterogeneous photocatalysis in flow chemical reactors

• Christopher G. Thomson,
• Ai-Lan Lee and
• Filipe Vilela

Beilstein J. Org. Chem. 2020, 16, 1495–1549, doi:10.3762/bjoc.16.125

• in Figure 4. The differences between inorganic and organic semiconductors are primarily the transport of charge within the material, which arise from the drastically different properties and various degrees of crystallinity of organic semiconductors, which we will now briefly discuss. In amorphous

• material is drastically different for inorganic and organic semiconductors. High εr(ω) materials, such as silicon (εr(ω) = 12) or GaAs (εr(ω) = 13), effectively screen the Coulombic attraction between excitons to 10s of meV, allowing the charge carriers to easily dissociate at room temperature [109][110

• . Hence, the charge mobility in organic semiconductors is typically much lower than in crystalline inorganic materials [115]. Conjugated polymers that are rigid will generally have faster intrachain charge transport rather than interlayer hopping transport (Figure 8) [107][115]. The process is highly

Dyes in modern organic chemistry

• Heiko Ihmels

Beilstein J. Org. Chem. 2019, 15, 2798–2800, doi:10.3762/bjoc.15.272

• dyes also contribute as essential components in modern applications such as in OLEDs [5][6], solar cells [7][8], organic semiconductors [9], NLO materials [10], photopolymerization [11], or Chemistry 4.0 [12]. From its very beginning, dye chemistry is strongly connected to the scientific developments

Synthesis of aryl-substituted thieno[3,2-b]thiophene derivatives and their use for N,S-heterotetracene construction

• Nadezhda S. Demina,
• Nikita A. Kazin,
• Nikolay A. Rasputin,
• Roman A. Irgashev and
• Gennady L. Rusinov

Beilstein J. Org. Chem. 2019, 15, 2678–2683, doi:10.3762/bjoc.15.261

• the synthesis of aryl-substituted 9H-thieno[2',3':4,5]thieno[3,2-b]indoles. These π-conjugated ring-fused molecules are of interest as electron-rich subunits for further organic semiconductors development. An example of an earlier developed S,N-heterohexacene [13] and general structure of compounds

Synthesis of aryl sulfides via radical–radical cross coupling of electron-rich arenes using visible light photoredox catalysis

• Amrita Das,
• Mitasree Maity,
• Simon Malcherek,
• Burkhard König and
• Julia Rehbein

Beilstein J. Org. Chem. 2018, 14, 2520–2528, doi:10.3762/bjoc.14.228

• . Keywords: arenes; oxidation; photocatalysis; thiolation; visible light; Introduction The generation of carbon–sulfur bonds is an important task in organic synthesis, because of their abundance in target structures, such as natural products and drugs [1][2][3]. They are found in organic semiconductors

Steric “attraction”: not by dispersion alone

• Ganna Gryn’ova and
• Clémence Corminboeuf

Beilstein J. Org. Chem. 2018, 14, 1482–1490, doi:10.3762/bjoc.14.125

• proteins [32], heteroaromatic cores that are the common building blocks for organic semiconductors [33], cyclophanes [34], Wilcox torsion balance systems [35], etc. The recognized importance of charge penetration in various chemical problems is paralleled by myriad developments aimed at accurately

Synthesis and application of trifluoroethoxy-substituted phthalocyanines and subphthalocyanines

• Satoru Mori and
• Norio Shibata

Beilstein J. Org. Chem. 2017, 13, 2273–2296, doi:10.3762/bjoc.13.224

• acceptor molecule, than to poly(3-hexylthiophene-2,5-diyl) (P3HT) [107], which is a known donor molecule. It can thus be concluded that TFEO-Pc can play a role as an acceptor-type semiconductor. In general, organic semiconductors have a greater abundance of donor-type molecules than acceptor-type molecules

• for the application in functional dyes with higher performance and in new industrial fields. An interesting example involves investigations on energy transfer between the phthalocyanine and the fullerene [101]. Normally, phthalocyanine plays the role as a donor type molecule in the field of organic

• semiconductors [102]. For example, a hybrid compound consisting of phthalocyanine and fullerene 20a causes the transfer of energy from the phthalocyanine unit to the fullerene unit when irradiated by light (Figure 6) [103][104]. However, such energy transfer does not occur in the hybrid of TFEO-ZnPc and

New electroactive asymmetrical chalcones and therefrom derived 2-amino- / 2-(1H-pyrrol-1-yl)pyrimidines, containing an N-[ω-(4-methoxyphenoxy)alkyl]carbazole fragment: synthesis, optical and electrochemical properties

• Daria G. Selivanova,
• Alexei A. Gorbunov,
• Olga A. Mayorova,
• Alexander N. Vasyanin,
• Igor V. Lunegov,
• Elena V. Shklyaeva and
• Georgii G. Abashev

Beilstein J. Org. Chem. 2017, 13, 1583–1595, doi:10.3762/bjoc.13.158

• street, 15, 614990, Perm, Russia Laboratory of organic semiconductors, Natural Sciences Institute, Perm State University, Genkel street, 4, 614990, Perm, Russia 10.3762/bjoc.13.158 Abstract In this paper we present a synthetic approach to six new D–π–A–D conjugated chromophores containing the N-[ω-(4

High performance p-type molecular electron donors for OPV applications via alkylthiophene catenation chromophore extension

• Paul B. Geraghty,
• Calvin Lee,
• Jegadesan Subbiah,
• Wallace W. H. Wong,
• James L. Banal,
• Mohammed A. Jameel,
• Trevor A. Smith and
• David J. Jones

Beilstein J. Org. Chem. 2016, 12, 2298–2314, doi:10.3762/bjoc.12.223

• devices with PTB7-Th resulting in high-performance OPV devices with up to 10.7% PCE. Keywords: molecular materials; nematic liquid crystal; organic solar cells; organic synthesis; p-type organic semiconductors; small molecule; Introduction Bulk heterojunction (BHJ) organic solar cells (OSC), a blend of

• materials synthesis and device architecture has pushed OSC power conversion efficiencies (PCEs) to 11.5% [4][5]. Further materials design and device optimizations have been proposed to deliver OSCs with PCEs up to 15% [6][7]. Although the field has been dominated by polymeric conjugated organic

• semiconductors, there has been a rapid advance in the development of MMs with PCEs over 10% now reported [8][9]. The switch to MMs has in part been due to their discrete structure and relative ease of purification, which offers significant advantages, especially reduced batch-to-batch variation [10][11][12]. We

Thiophene-forming one-pot synthesis of three thienyl-bridged oligophenothiazines and their electronic properties

• Dominik Urselmann,
• Konstantin Deilhof,
• Bernhard Mayer and
• Thomas J. J. Müller

Beilstein J. Org. Chem. 2016, 12, 2055–2064, doi:10.3762/bjoc.12.194

• charge-carrying materials [2][3][27][28] and organic semiconductors [29][30] in electronic [31] and optoelectronic devices [32][33][34]. As reversibly oxidizable units 2,5-di(hetero)aryl-substituted thiophenes are additionally interesting as redox switchable molecular wires [35][36] in unimolecular

Effect of the π-conjugation length on the properties and photovoltaic performance of A–π–D–π–A type oligothiophenes with a 4,8-bis(thienyl)benzo[1,2-b:4,5-b′]dithiophene core

• Ni Yin,
• Lilei Wang,
• Yi Lin,
• Jinduo Yi,
• Lingpeng Yan,
• Junyan Dou,
• Hai-Bo Yang,
• Xin Zhao and
• Chang-Qi Ma

Beilstein J. Org. Chem. 2016, 12, 1788–1797, doi:10.3762/bjoc.12.169

• for constructing high-performance A–π–D–π–A-type organic semiconductors for organic solar cells, where A represents the terminal electron acceptor unit, D represents the core electron donor unit, and π represents the conjugated π-bridge [13][14], and a maximum PCE of 9.95% was reported for a

Star-shaped and linear π-conjugated oligomers consisting of a tetrathienoanthracene core and multiple diketopyrrolopyrrole arms for organic solar cells

• Hideaki Komiyama,
• Chihaya Adachi and
• Takuma Yasuda

Beilstein J. Org. Chem. 2016, 12, 1459–1466, doi:10.3762/bjoc.12.142

• (40–60 nm). Keywords: bulk heterojunction; diketopyrrolopyrrole; organic solar cells; star-shaped oligomers; tetrathienoanthracene; Introduction Solution-processable organic semiconductors have been intensively studied as key materials for low-cost, flexible, and large-area optoelectronic devices