The charge transport properties of dicyanomethylene-functionalised violanthrone derivatives

• Sondos A. J. Almahmoud,
• Joseph Cameron,
• Dylan Wilkinson,
• Michele Cariello,
• Claire Wilson,
• Alan A. Wiles,
• Peter J. Skabara and
• Graeme Cooke

Beilstein J. Org. Chem. 2024, 20, 2921–2930, doi:10.3762/bjoc.20.244

• that the three materials might function effectively as electron acceptors. OFET device studies The electrical characteristics were confirmed by the fabrication of OFETs. Compounds 3a–c were deposited by spin-coating onto n-doped Si/SiO2/Au substrates. The device performance parameters are summarised in

Synthesis and characterization of 1,2,3,4-naphthalene and anthracene diimides

• Adam D. Bass,
• Daniela Castellanos,
• Xavier A. Calicdan and
• Dennis D. Cao

Beilstein J. Org. Chem. 2024, 20, 1767–1772, doi:10.3762/bjoc.20.155

• described isomers and expand the toolbox of electron-deficient aromatic compounds available to organic materials chemists. Keywords: electron acceptors; organic materials; polycyclic aromatic hydrocarbons; Introduction Aromatic diimides are ubiquitous molecular scaffolds that have served as the basis for

Synthesis of indano[60]fullerene thioketone and its application in organic solar cells

• Yong-Chang Zhai,
• Shimon Oiwa,
• Shinobu Aoyagi,
• Shohei Ohno,
• Tsubasa Mikie,
• Jun-Zhuo Wang,
• Hirofumi Amada,
• Koki Yamanaka,
• Kazuhira Miwa,
• Naoyuki Imai,
• Takeshi Igarashi,
• Itaru Osaka and
• Yutaka Matsuo

Beilstein J. Org. Chem. 2024, 20, 1270–1277, doi:10.3762/bjoc.20.109

• (FIDO, FIDS, C60) as electron-acceptors were compared, and the open-circuit voltage with FIDS was 0.16 V higher than that with C60. Keywords: C60; evaporable fullerene derivatives; organic photovoltaics; organic solar cells; thioketone; Introduction Fullerene is a carbon allotrope that has attracted

• derivatives have played an important role both in OPVs as electron acceptors and in PSCs as electron transport layers (ETLs) by efficiently accepting electrons and hindering the transport of holes [12][13][14]. During the past 10 years, considerable attention has been focused on functional fullerene

• evaporable fullerene derivatives as electron acceptors. FIDO exhibited the best performance, with VOC that was 0.18 V higher compared with C60. Although FIDS showed a lower performance due to its less-desirable BHJ structure in the OPV, it could still potentially be utilized in perovskite solar cells in the

Two-fold addition reaction of silylene to C₆₀: structural and electronic properties of a bis-adduct

• Masahiro Kako,
• Masato Kai,
• Masanori Yasui,
• Michio Yamada,
• Yutaka Maeda and
• Takeshi Akasaka

Beilstein J. Org. Chem. 2024, 20, 1179–1188, doi:10.3762/bjoc.20.100

• with excellent properties as organic photovoltaic materials [9][10][11][12][13][14]. Furthermore, regioisomerically pure bis-functionalized fullerenes function better as electron acceptors in organic thin-film solar cells than mixtures of the corresponding regioisomers do [12][13][14]. Therefore

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

• guaranteeing long-lived CS states. Guldi et al. synthesized 16 distinct donor–acceptor conjugated molecules, denoted as 89–104 (Figure 11). These molecules comprised ZnP as an electron donor and push–pull chromophores with varying reduction potentials as electron acceptors interconnected by various rigid

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

• acetylenic scaffolds comprised of enediyne units are known to behave as good electron acceptors [15][16], and we became interested in combining the IF-DTF scaffold with such motifs to generate novel multi-redox systems. For example, the radiaannulene moiety RA shown in Figure 1 (or its truncated counterpart

Controlling the reactivity of La@C₈₂ by reduction: reaction of the La@C₈₂ anion with alkyl halide with high regioselectivity

• Yutaka Maeda,
• Saeka Akita,
• Mitsuaki Suzuki,
• Michio Yamada,
• Takeshi Akasaka,
• Kaoru Kobayashi and
• Shigeru Nagase

Beilstein J. Org. Chem. 2023, 19, 1858–1866, doi:10.3762/bjoc.19.138

• structure is described as La3+C823−. We previously investigated the reaction of M@C2v-C82 ions (M = Y, La, Ce) with disilirane, which possesses high reactivity toward electron acceptors [16][17]. Interestingly, the reactivity of M@C2v-C82 toward disilirane was increased by the one-electron oxidation of M

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

• conduction of electrons [16]. Perylene diimide derivatives display good electronic mobilities (10−3 to 10−1 cm2 V−1 s−1) and are considered suitable electron acceptors for photovoltaic applications [17][18][19][20]. Pyrene derivatives have also been widely investigated in recent decades. They exhibit

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

• their performance as electron acceptors. Researchers have focused on improving multi-dimensional electron transport, enhancing electron injection, addressing stability concerns, optimizing side chain engineering, and refining fabrication processes. One notable study by Wang et al. demonstrated the

• aggregation of fullerene molecules within the polymer matrix [25]. Small molecule NFAs have significantly advanced the field of OSCs. Notably, the fused-ring electron acceptors (FREAs) have exhibited exceptional promise, heralding a new era of possibilities for OSC technology. In 2019, Yuan et al. reported on

• currently at the forefront and delivering great PCE, unfused electron acceptors have continued to garner considerable attention. Chang and co-workers focused on enhancing the aggregation and crystallinity of unfused Qx acceptors, Qx17 and Qx18, containing a Qx core and different halogenated end groups. Both

A series of perylene diimide cathode interlayer materials for green solvent processing in conventional organic photovoltaics

• Kathryn M. Wolfe,
• Shahidul Alam,
• Eva German,
• Fahad N. Alduayji,
• Maryam Alqurashi,
• Frédéric Laquai and
• Gregory C. Welch

Beilstein J. Org. Chem. 2023, 19, 1620–1629, doi:10.3762/bjoc.19.119

• , reaching PCEs of ≈6% [23]. Realizing that these materials are suitable electron acceptors, it was hypothesized that the monomeric species would be suitable candidates for use as CILs as the planar structure is more likely to induce ordered microstructures, which is ideal for CILs as a means to provide

Enabling artificial photosynthesis systems with molecular recycling: A review of photo- and electrochemical methods for regenerating organic sacrificial electron donors

• Grace A. Lowe

Beilstein J. Org. Chem. 2023, 19, 1198–1215, doi:10.3762/bjoc.19.88

• shown for the one-electron-reduced viologen species ([methyl viologen]•− −0.59 V vs SCE, [ethylcarboxy viologen]•− −0.49 V vs SCE, [ethylamide viologen]•− −0.42 V vs SCE) [59]. Viologens usually act as electron acceptors in aqueous RFB anolytes. In general, RFB anolytes are optimized to have very low

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

• acids B(C6F5)3 and B(C6H5)3 as electron acceptors, respectively [29]. B(C6F5)3 displays high chemical stability and Lewis acidity [30]. Moreover, its good solubility endows the possibility to form Lewis acid–base adducts in films by solution processing. The strong electron attraction of the fluorine

• brand new luminescent properties. In this mini-review, we summarize unique electron donor and acceptor materials which regulate luminescent properties via Lewis acid–base interactions and briefly explain the exploration of their chemical nature and interaction mechanisms. Review Lewis acids as electron

• acceptors Some Lewis acids have good solubility in common organic solvents, which makes it easy to fabricate films for optoelectronic applications [24]. Because of their strong electrophilicity [25], Lewis acids may dominate charge distributions of the fluorescent materials featured with electron-rich

Chemical syntheses and salient features of azulene-containing homo- and copolymers

• Vijayendra S. Shetti

Beilstein J. Org. Chem. 2021, 17, 2164–2185, doi:10.3762/bjoc.17.139

• for 81 and 0.24 cm2 V−1 s−1 for 83. The polymer 81 with an electron mobility of 0.42 cm2 V−1 s−1 represents one of the best unipolar n-type polymers for OFET applications. These polymers were also tested as electron acceptors for all-polymer solar cell (PSC) devices, and 81 in particular, showed a

Biochemistry of fluoroprolines: the prospect of making fluorine a bioelement

• Vladimir Kubyshkin,
• Rebecca Davis and
• Nediljko Budisa

Beilstein J. Org. Chem. 2021, 17, 439–460, doi:10.3762/bjoc.17.40

• the aliphatic C–H bonds of the proline ring serve as electron acceptors. This phenomenon is known as the aromatic-proline motif [42][43]. The substitution of a hydrogen atom at position 4 by fluorine inverts the sign of the potential. The fluorine atom creates a surface that is negatively charged

Exploring the possibility of using fluorine-involved non-conjugated electron-withdrawing groups for thermally activated delayed fluorescence emitters by TD-DFT calculation

• Dongyang Chen and
• Eli Zysman-Colman

Beilstein J. Org. Chem. 2021, 17, 210–223, doi:10.3762/bjoc.17.21

• for efficient TADF if the donor and acceptor moieties are poorly conjugated with each other in order to minimize J. The HOMO/LUMO separation that controls J can be modulated by introducing strong and bulky electron donors and electron acceptors to produce large torsions between the donor and acceptor

Insight into functionalized-macrocycles-guided supramolecular photocatalysis

• Minzan Zuo,
• Krishnasamy Velmurugan,
• Kaiya Wang,
• Xueqi Tian and
• Xiao-Yu Hu

Beilstein J. Org. Chem. 2021, 17, 139–155, doi:10.3762/bjoc.17.15

• accessible for MO and ii) the Au cores could perform as electron acceptors (Au+ to Au0), which prevents the recombination of the electron–hole pairs produced by TiO2. Such a system generated more excited electrons for the generation of reactive oxygen species (ROS) and also acted as an effective reaction

Photocatalysis with organic dyes: facile access to reactive intermediates for synthesis

• Stephanie G. E. Amos,
• Marion Garreau,
• Luca Buzzetti and
• Jerome Waser

Beilstein J. Org. Chem. 2020, 16, 1163–1187, doi:10.3762/bjoc.16.103

• decomposition [69][70], these species are straightforward to synthesize and can be easily reduced (Ered ≈ −0.1 V to −0.3 V) [71][72]. This makes them valuable electron acceptors for photocatalytic strategies. The SET reduction results in the generation of an aryl radical upon the irreversible loss of N2 as the

Cation-induced ring-opening and oxidation reaction of photoreluctant spirooxazine–quinolizinium conjugates

• Phil M. Pithan,
• Sören Steup and
• Heiko Ihmels

Beilstein J. Org. Chem. 2020, 16, 904–916, doi:10.3762/bjoc.16.82

• -step electron transfer from the merocyanine to the metal cations, which acted as electron acceptors. Similarly, Malatesta et al. found that the thermal dark reaction of spironaphthoxazines in the presence of a suitable electron acceptor, such as 7,7,8,8-tetracyanoquinodimethane, gave the corresponding

Photophysics and photochemistry of NIR absorbers derived from cyanines: key to new technologies based on chemistry 4.0

• Bernd Strehmel,
• Christian Schmitz,
• Ceren Kütahya,
• Yulian Pang,
• Anke Drewitz and
• Heinz Mustroph

Beilstein J. Org. Chem. 2020, 16, 415–444, doi:10.3762/bjoc.16.40

• imaging applications. This would definitively decrease the efficiency of electron back transfer. Nowadays, typical electron acceptors (AC) applied in such systems related to either iodonium salts or triazines also possess a high capability of electron back transfer resulting in a decrease of the overall

D–A–D-type orange-light emitting thermally activated delayed fluorescence (TADF) materials based on a fluorenone unit: simulation, photoluminescence and electroluminescence studies

• Lin Gan,
• Xianglong Li,
• Xinyi Cai,
• Kunkun Liu,
• Wei Li and
• Shi-Jian Su

Beilstein J. Org. Chem. 2018, 14, 672–681, doi:10.3762/bjoc.14.55

• donors (D) and electron acceptors (A) are introduced into the molecule to form an intramolecular charge transfer (ICT) state with a large twisting angle between the donor and the acceptor to achieve the separation of highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO

Recent advances on organic blue thermally activated delayed fluorescence (TADF) emitters for organic light-emitting diodes (OLEDs)

• Thanh-Tuân Bui,
• Fabrice Goubard,
• Malika Ibrahim-Ouali,
• Didier Gigmes and
• Frédéric Dumur

Beilstein J. Org. Chem. 2018, 14, 282–308, doi:10.3762/bjoc.14.18

• investigated in organic electronics [31] as these materials are characterized by a remarkable electron mobility resulting from the presence of a vacant p-orbital on the boron atom [32][33]. Triarylboron compounds are also strong electron acceptors, justifying that numerous groups developed TADF emitters using

• -TADF white OLEDs with 16% EQE could be fabricated [30]. 4. Triazine–pyrimidine based emitters Among possible electron acceptors, another structure has been extensively regarded as an adequate electron acceptor for the design of blue TADF emitters and this structure is the triazine unit. When combined

• OLEDs, what is remarkable. Conversely, a less blue emission was obtained for T32, the emission peaking in the blue-green region (497 nm). 5. Phenoxaphosphine oxide and phenoxathiin dioxide derivatives Recently, phenoxaphosphine oxide and phenoxathiin dioxide have gained interest as electron acceptors

Dialkyl dicyanofumarates and dicyanomaleates as versatile building blocks for synthetic organic chemistry and mechanistic studies

• Grzegorz Mlostoń and
• Heinz Heimgartner

Beilstein J. Org. Chem. 2017, 13, 2235–2251, doi:10.3762/bjoc.13.221

• with diethyl phosphite in boiling 1,2-dichloroethane leading to the dialkyl dicyanosuccinates 96 [7]. Charge-transfer (CT) complexes Dialkyl dicyanofumarates E-1, similar to tetracyanoethylene (TCNE), are well-known as one-electron acceptors. They react with metallocenes 99, such as manganocenes [73

• , such as 1,2-diamines and β-aminoalcohols are of special importance as they offer access to a variety of heterocycles through an addition–elimination–heterocyclization sequence. Their ability to act as single-electron acceptors, demonstrated in the reaction with thiols and selenols, allows their

Regiodivergent condensation of 5-alkoxycarbonyl-1H-pyrrol-2,3-diones with cyclic ketazinones en route to spirocyclic scaffolds

• Alexey Yu. Dubovtsev,
• Maksim V. Dmitriev,
• Аndrey N. Maslivets and
• Michael Rubin

Beilstein J. Org. Chem. 2017, 13, 2179–2185, doi:10.3762/bjoc.13.218

• product of 1,2-addition of the C-nucleophile to the most reactive keto function and subsequent nucleophilic attack by the O-enolate on the conjugate C=C bond activated by two electron acceptors could become more preferable as compared to the alternative “normal” pathway, leading to adducts 10 and

Conformational impact of structural modifications in 2-fluorocyclohexanone

• Francisco A. Martins,
• Josué M. Silla and
• Matheus P. Freitas

Beilstein J. Org. Chem. 2017, 13, 1781–1787, doi:10.3762/bjoc.13.172

• , the π*C=Y orbitals (Y = O, S and N) are better electron acceptors than the π*C=C in electron delocalization processes. These highlight the role of electrostatic and hyperconjugative effects on the conformational isomerism of the studied compounds. Two particularly clear trends are related to the NH

Synthesis and characterization of fluorinated azadipyrromethene complexes as acceptors for organic photovoltaics

• Forrest S. Etheridge,
• Roshan J. Fernando,
• Sandra Pejić,
• Matthias Zeller and
• Geneviève Sauvé

Beilstein J. Org. Chem. 2016, 12, 1925–1938, doi:10.3762/bjoc.12.182

• Homoleptic zinc(II) complexes of di(phenylacetylene)azadipyrromethene (e.g., Zn(WS3)2) are potential non-fullerene electron acceptors for organic photovoltaics. To tune their properties, fluorination of Zn(WS3)2 at various positions was investigated. Three fluorinated azadipyrromethene-based ligands were

• substitution at the pyrrolic phenylacetylene moieties. The later complexes are expected to be stronger electron acceptors than Zn(WS3)2, and may enable charge transfer from other conjugated polymer donors that have lower energy levels than poly(3-hexylthiophene) (P3HT). Keywords: dye; fluorine; near-IR

• chelation [1][2][3][4]. BF2+-chelated ADP derivatives (Figure 1b) in particular have drawn interest for photodynamic therapy, bio-imaging and light harvesting applications [5][6][7][8]. We have shown that derivatives of Zn(ADP)2 are promising electron acceptors for organic photovoltaics (OPVs) [9][10]. A