Acyclic cucurbit[n]uril bearing alkyl sulfate ionic groups

• Christian Akakpo,
• Peter Y. Zavalij and
• Lyle Isaacs

Beilstein J. Org. Chem. 2025, 21, 717–726, doi:10.3762/bjoc.21.55

• are acyclic CB[n]-type receptors which have been extensively studied by our lab and others over the past decade [42][43][44][45][46][47][48][49][50][51][52]. Figure 1 shows the chemical structure of the prototypical acyclic CB[n]-type known as M1 [53][54]. M1 features a central glycoluril tetramer

• modular synthesis, acyclic CB[n] can be easily modified synthetically [42][43][44][45][46][47][61]. Acyclic CB[n]-type receptors featuring different length glycoluril oligomers (monomer–pentamer) and different aromatic walls (e.g., naphthalene, anthracene, triptycene) have been studied [42][62][63][64][65

• sulfate). In this paper, we present the synthesis and molecular recognition properties of a new acyclic CB[n]-type receptor C1 which allows us to disentangle these two effects. Results and Discussion This results and discussion section is organized as follows: First, we present the design, synthesis, and

Photochemically assisted synthesis of phenacenes fluorinated at the terminal benzene rings and their electronic spectra

• Yuuki Ishii,
• Minoru Yamaji,
• Fumito Tani,
• Kenta Goto,
• Yoshihiro Kubozono and
• Hideki Okamoto

Beilstein J. Org. Chem. 2025, 21, 670–679, doi:10.3762/bjoc.21.53

• molecules displayed high hole mobility [20][21][22][23][24][25][26] and imide-fused phenacenes served as n-type organic semiconductors [27]. It was also disclosed that donor–acceptor-type phenacenes provided environment-dependent fluorophores showing solvatochromic fluorescence behavior [28][29]. Because

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

• ]. Among many intensively investigated organic semiconductors [10][11][12], are perylene diimide (PDI) derivatives which feature a rigid, planar, fused π-skeleton. These molecules have been widely utilised as n-type materials, due to their exceptional charge mobility (μe ≈ 0.1–2.1 cm2 V−1 s−1) [13][14][15

• the incorporation of the strong electron-withdrawing dicyanomethylene unit. The study suggested that 3b could be a potential n-type material for OPVs. The incorporation of two dicyanomethylene groups resulted in a material with strong electron affinity and low reduction potential of −0.56 V vs NHE

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

• -) derivatization of aromatic scaffolds because it can be exploited to stabilize the longer (hetero)acenes. In contrast to cata-benzannulation, cata-imide-annulation does not perturb aromaticity patterns and further introduces inductive stabilization of frontier MO levels, which has enabled the production of n-type

Structure–property relationships in dicyanopyrazinoquinoxalines and their hydrogen-bonding-capable dihydropyrazinoquinoxalinedione derivatives

• Tural N. Akhmedov,
• Ajeet Kumar,
• Daken J. Starkenburg,
• Kyle J. Chesney,
• Khalil A. Abboud,
• Novruz G. Akhmedov,
• Jiangeng Xue and
• Ronald K. Castellano

Beilstein J. Org. Chem. 2024, 20, 1037–1052, doi:10.3762/bjoc.20.92

• . Primary motivation for our effort comes from the work of Yamashita et al. who explored the OFET behavior of a library of electron-deficient dicyanopyrazinoquinoxaline (DCPQ) compounds [25]. The computations predicted low-lying LUMO levels, around −4.0 eV. However, the molecules exhibited poor n-type FET

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

• semiconductor layer of n-type organic field-effect transistors. Typically, an electron transport material should have a high electron mobility and a low-lying lowest unoccupied molecular orbital (LUMO) relative to vacuum. This is achieved by using electron-deficient units containing highly electronegative

• orthogonal processing. One of the biggest challenges with n-type materials is air stability. This is explained by the redox potentials of water (−0.66 V vs standard calomel electrode (SCE)) and oxygen (+0.024 V vs SCE, +0.57 V vs SCE) [2][3]. Therefore, it has been observed that once the overpotential

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

• , Yamada, Fukui, Shinokubo and co-workers tackled the synthesis of perylene bisimide (PBI), a valuable n-type semiconductor, via a “precursor approach” based on the late-stage extrusion of S-based fragments [57]. Dinaphthothiepine bisimides 3a and 3b, bearing octyl- and butylimide substituents respectively

• annealing at 230 °C for 5 min to induce SO-extrusion and subsequent vacuum deposition of the source and drain gold electrodes, the resulting OFET exhibited a typical n-type behavior with an electron mobility up to 0.41 cm2 V−1 s−1, comparable to vacuum deposited films of pristine PBI. When repeating the

• , and the dinaphthothiepine S-oxides bearing long alkyl chains are thus very promising soluble precursors to afford n-type semiconducting layers by in situ SO-extrusion. As part of their work dedicated to mechanically-responsive materials controlled by an electrochemical stimulus, Song and Swager

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

• understanding charge transport in columnar mesophases [9][10][11][12][13][14]. High charge carrier mobilities of 1.1 cm2 V−1 s−1 for p-type and up to 6.0 cm2 V−1 s−1 for n-type liquid-crystalline semiconductors have already been reported [15]. Among the various discotic liquid crystal materials, perylene

• derivatives are among the most investigated due to their easy functionalization, high chemical and thermal stability, strong photoluminescence, and n-type semiconductor character. They tend to adopt columnar organization due to the strong π–π interaction of the rigid cores, providing a path for the efficient

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 field-effect transistors (OFETs), organic-light emitting diodes (OLEDs) and other organic electronic technologies. Notably, the potential of quinoxaline derivatives as non-fullerene acceptors in OSCs, auxiliary acceptors and bridging materials in DSSCs, and n-type semiconductors in transistor

• transport applications. Furthermore, ongoing research efforts aimed at enhancing their performance and addressing key challenges in various applications are presented. Keywords: electron transport materials; non-fullerene acceptors; n-type semiconductors; organic electronics; quinoxalines; Introduction

• charge separation in all-PSCs such as switching from p-type dominated behaviour of polymer Qx5 to n-type dominated behaviour of Q6, with no off state due to presence of free charge carriers in the latter case [21]. Besides optimizing polymer structures, side chain engineering, introduction of electron

Mechanochemical bottom-up synthesis of phosphorus-linked, heptazine-based carbon nitrides using sodium phosphide

• Blaine G. Fiss,
• Georgia Douglas,
• Michael Ferguson,
• Jorge Becerra,
• Jesus Valdez,
• Trong-On Do,
• Tomislav Friščić and
• Audrey Moores

Beilstein J. Org. Chem. 2022, 18, 1203–1209, doi:10.3762/bjoc.18.125

• well as a peak centered on 292.1 eV due to charging effects [39]. The presence of C=N bonds established by XPS indicates that the heptazine structure was preserved during milling and aging with Na3P. Nitrogen 1s focused scans of g-h-PCN showed a 62% to 38% ratio of pyridinic to pyridonic-N type

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

Beyond ribose and phosphate: Selected nucleic acid modifications for structure–function investigations and therapeutic applications

• Christopher Liczner,
• Kieran Duke,
• Gabrielle Juneau,
• Martin Egli and
• Christopher J. Wilds

Beilstein J. Org. Chem. 2021, 17, 908–931, doi:10.3762/bjoc.17.76

• -phosphate backbone relative to native phosphodiester oligomers. This N-type sugar puckering and increased hydration of the sugar phosphate backbone could also account for the triplex-favoring properties of this modification [72]. Amide While many amide backbone oligonucleotide variants exist, the focus of

• modified with the 4'-methoxy modification hybridized better to complementary RNA, rather than DNA, due to the N-type conformation of the sugar pucker, as confirmed by NMR [202]. These same oligomers exhibited half-lives of approximately 40 minutes in the presence of phosphodiesterase I [202]. In contrast

Dirhamnolipid ester – formation of reverse wormlike micelles in a binary (primerless) system

• David Liese,
• Hans Henning Wenk,
• Xin Lu,
• Jochen Kleinen and
• Gebhard Haberhauer

Beilstein J. Org. Chem. 2020, 16, 2820–2830, doi:10.3762/bjoc.16.232

• camera. Atomic force microscopy Atomic force microscopy (AFM) images were performed in the tapping mode using a NanoDrive Controller with an Innova Scanning Probe Microscope (Veeco) and an N-type silicon cantilever (Olympus AC 16TS). The samples were prepared by drop-coating the solution (50 µM) on a

Naphthalene diimide bis-guanidinio-carbonyl-pyrrole as a pH-switchable threading DNA intercalator

• Poulami Jana,
• Filip Šupljika,
• Carsten Schmuck and
• Ivo Piantanida

Beilstein J. Org. Chem. 2020, 16, 2201–2211, doi:10.3762/bjoc.16.185

• compound 4 to DNA. For each measurement, 10 μL of the mixed solution were deposited onto a freshly cleaned mica surface (Plano GmbH). The sample was dried by means of a spin-coater (1 min at 20 rps and 2 min at 100 rps). For the AFM imaging operating in the tapping mode (scan rate 5 μm s−1) with N-type

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

• ) showed an n-type behavior. In their synthesis and structural as well as electronic characterization of F4PEN 3, Bettinger et al. showed that the electronic properties of pentacenes are not a simple linear function of the degree of fluorination [7][8]. They reported that the fluorination in the 2,3,9,10

Synthesis of novel multifunctional carbazole-based molecules and their thermal, electrochemical and optical properties

• Nuray Altinolcek,
• Ahmet Battal,
• Mustafa Tavasli,
• William J. Peveler,
• Holly A. Yu and
• Peter J. Skabara

Beilstein J. Org. Chem. 2020, 16, 1066–1074, doi:10.3762/bjoc.16.93

• homoleptic or heteroleptic iridium(III) complexes were also reported in the construction of different OLEDs [10][11][12][13]. In OPVs, carbazole derivatives are frequently used as small molecule p-type (electron-donating) materials or electron-accepting (n-type) materials with a variety of donor–acceptor

Recent advances in Cu-catalyzed C(sp³)–Si and C(sp³)–B bond formation

• Balaram S. Takale,
• Ruchita R. Thakore,
• Elham Etemadi-Davan and
• Bruce H. Lipshutz

Beilstein J. Org. Chem. 2020, 16, 691–737, doi:10.3762/bjoc.16.67

• ]. Following this report, Oestreich and co-workers examined asymmetric additions of silicon to unsaturated ketones 113 using P–N-type ligand L13. However, the background reaction of the silyl–zinc reagent was predominant leading to poor chirality transfer from the phosphine ligand L13, giving essentially the

Synthesis of 2H-furo[2,3-c]pyrazole ring systems through silver(I) ion-mediated ring-closure reaction

• Vaida Milišiūnaitė,
• Rūta Paulavičiūtė,
• Eglė Arbačiauskienė,
• Vytas Martynaitis,
• Wolfgang Holzer and
• Algirdas Šačkus

Beilstein J. Org. Chem. 2019, 15, 679–684, doi:10.3762/bjoc.15.62

• −127.5 to −128.0 ppm for N-1. The structure of 4d was investigated additionally by single crystal X-ray analysis (Figure 1) [39]. The asymmetric unit of the crystal consists of two molecules 4d(A) and 4d(B) held together by the weak CH···N type hydrogen bonds C19–H···N51 (C···N = 3.470(11) Å, H···N

Nucleoside macrocycles formed by intramolecular click reaction: efficient cyclization of pyrimidine nucleosides decorated with 5'-azido residues and 5-octadiynyl side chains

• Jiang Liu,
• Peter Leonard,
• Sebastian L. Müller,
• Constantin Daniliuc and
• Frank Seela

Beilstein J. Org. Chem. 2018, 14, 2404–2410, doi:10.3762/bjoc.14.217

• = 173°) [48] adopt an anti-conformation [49]. The conformation of the 2’-deoxyribofuranosyl moiety of 8 shows an C3’-endo envelope pucker (4E, N-type) in the solid state with a pseudorotational phase angle P = 50.2(2)° and a maximum amplitude of τm = 38.7(1)°. The extended structure forms a three

• for cyclo-dU 8 and 68% S-type for cyclo-dC 4. The conformation found for the macrocycle 8 is different to that in the solid state (N-type, Figure 4). Apparently, the sugar residue of the macrocycle exhibits sufficient flexibility to adopt the S-conformation of DNA and the N-conformation of RNA

Recent advances in phosphorescent platinum complexes for organic light-emitting diodes

• Cristina Cebrián and
• Matteo Mauro

Beilstein J. Org. Chem. 2018, 14, 1459–1481, doi:10.3762/bjoc.14.124

• in spite of the stronger ligand-field exerted. Similar to the case of C^N^N type of ligands, a significant structural distortion is the main factor that accounts for this low emission efficiency. However, Che and co-workers demonstrated that extension of the π-conjugation at the tridentate ligand

Enzymatic separation of epimeric 4-C-hydroxymethylated furanosugars: Synthesis of bicyclic nucleosides

• Neha Rana,
• Manish Kumar,
• Vinod Khatri,
• Jyotirmoy Maity and
• Ashok K. Prasad

Beilstein J. Org. Chem. 2017, 13, 2078–2086, doi:10.3762/bjoc.13.205

• ring puckering in bicyclic nucleoside and the sugar ring puckering is locked in N-type conformation (Figure 3). The structures of all the synthesized compounds, i.e., 4a, 4b, 5, 6, 7a,b, 8–11, 12a,b, 13 and 14 were unambiguously established on the basis of their spectral data (1H and 13C NMR spectra

• , from respective biaocatalytic monoacetylated product. The crystal structure of one of the synthesized bicyclic nucleosides, 2′-O,4′-C-methylene-xylouridine (14) revealed N-type puckering of the sugar ring of the compound. The developed biocatalytic methodology will have significant impact in the area

• and 10. ORTEP diagram and preferential N-type sugar ring puckering of 2′-O,4′-C-methylene-xylouridine (14). Formation of a 1:1 epimeric mixture of 3a and 3b. Lipase-catalysed separation of a mixture of ribo- and xylotrihydroxyfuranosides. Convergent synthesis of 3′-O,4′-C-methyleneuridine. Convergent

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

• p-type and n-type conjugated polymers or molecular materials (MM), have attracted significant attention as alternative solar cell technologies as they are light-weight, low-cost and offer the opportunity of cheaper manufacturing employing roll-to-roll printing processes [1][2][3]. Recent advances in

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

• known, fluorinated n-type materials are less common [13][30][31]. Nevertheless, fluorinated n-type materials have been shown to exhibit promising characteristics in devices. For instance, the addition of fluorinated groups to naphthalene diimide (NDI) and perylene diimide (PDI) derivatives increased the

• fluorinated derivatives allow access to triplet state blue light-emitters [13]. This work further investigates the effects of fluorination in n-type materials for OPVs. A series of selectively fluorinated ADP derivatives based on WS3 were synthesized (Figure 2). To understand the effect of the fluorination

Biosynthesis of oxygen and nitrogen-containing heterocycles in polyketides

• Franziska Hemmerling and
• Frank Hahn

Beilstein J. Org. Chem. 2016, 12, 1512–1550, doi:10.3762/bjoc.12.148

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

• grain growth, so the size of the crystalline domain in the film was higher in this case. These larger crystalline domains in films spin-coated from chloroform were beneficial for field effect mobility. None of the OFETs showed any n-type mobility. The extended character of the HOMO residing on the

• dithienyl-thieno-TTF unit and the localised nature of the LUMO led to donor–acceptor interactions in the solid phase, making it impossible for efficient overlap between LUMOs, which would normally be required for an efficient n-type semiconductor. BHJSCs were fabricated from 48 as the electron donor and