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

• significant scientific interest since its discovery by H. W. Kroto in 1985 [1]. Due to their distinctive spherical structure and electron-deficient properties, fullerene derivatives have found applications in various fields, including photovoltaics [2][3][4][5], biomedicine [6][7][8], and electron

Mechanistic investigations of polyaza[7]helicene in photoredox and energy transfer catalysis

• Johannes Rocker,
• Till J. B. Zähringer,
• Matthias Schmitz,
• Till Opatz and
• Christoph Kerzig

Beilstein J. Org. Chem. 2024, 20, 1236–1245, doi:10.3762/bjoc.20.106

• ][13][14][15]. Most of the established organic catalysts (acridinium salts [16][17][18][19], cyanoarenes [8][20][21][22], quinones [23][24], etc.) [10][25] are cationic or electron-deficient and tend to act as excited state oxidants in a reductive quenching cycle. Only recently, more reducing catalyst

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

• behavior and electron transport characteristics (μe = 1 × 10−8 to 3.6 × 10−6 cm2/Vs). Structurally, the combination of cyano groups and an electron-deficient pyrazinoquinoxaline creates an extremely electron poor π-system. Given our previous work and that of others, in 2013 we reasoned [26] that DCPQs

•  1). The H-bonding capable dihydropyrazinoquinoxaline diones (DPQDs) were obtained by a SNAr mechanism involving the corresponding DCPQ derivatives. Based on numerous examples in the literature, it has been established that for electron-deficient π-systems containing cyano groups, the addition

Auxiliary strategy for the general and practical synthesis of diaryliodonium(III) salts with diverse organocarboxylate counterions

• Naoki Miyamoto,
• Daichi Koseki,
• Kohei Sumida,
• Elghareeb E. Elboray,
• Naoko Takenaga,
• Ravi Kumar and
• Toshifumi Dohi

Beilstein J. Org. Chem. 2024, 20, 1020–1028, doi:10.3762/bjoc.20.90

• trifluoroacetic acid, followed by coupling with 1,3,5-trimethoxybenzene [18] (Scheme 1A). This process demonstrated tolerance for a wide range of electron-rich and electron-deficient (hetero)aryl iodine(III) compounds. Wirth and colleagues reported the flow synthesis of diaryliodonium(III) trifluoroacetates using

• 5b–f was explored with benzoic acid (6a) and 1,3,5-trimethoxybenzene (Scheme 5B). Iodosoarenes with electron-rich (5b, 5c, 5f), electron-deficient (5d), bromo (5e), and sterically hindered substituents (5f) were applicable to give the corresponding aryl(TMP)iodonium(III) benzoates 7ba–fa in 63–93

(Bio)isosteres of ortho- and meta-substituted benzenes

• H. Erik Diepers and
• Johannes C. L. Walker

Beilstein J. Org. Chem. 2024, 20, 859–890, doi:10.3762/bjoc.20.78

• (±)-30. In a related strategy, Procter and co-workers prepared 1,2-BCHs (±)-33a–e from BCBs 32 via a SmI2-catalysed radical relay alkene insertion (Scheme 3C) [35]. This approach relied on single-electron reduction of the ketone moiety and ring-expansion from the ketyl radical anion. Electron-deficient

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

A laterally-fused N-heterocyclic carbene framework from polysubstituted aminoimidazo[5,1-b]oxazol-6-ium salts

• Andrew D. Gillie,
• Matthew G. Wakeling,
• Bethan L. Greene,
• Louise Male and
• Paul W. Davies

Beilstein J. Org. Chem. 2024, 20, 621–627, doi:10.3762/bjoc.20.54

• only two sharp CO stretching frequencies were observed in the IR (Scheme 2) and so a value for Tolman’s electronic parameter (TEP) could be estimated. [33] At TEP[Ir] = 2053.1 cm−1 and 2052.8 cm−1 for 15a and 15b, respectively, the values for these AImOx ligands are towards the electron-deficient end

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

• switched off by the TTF oxidation at low potentials, leading to electrostatic repulsion between the positively charged TTF and electron-deficient acceptor counterparts [90]. The conformation of such structures was studied by the Azov group using TTF tweezers 43 with flexible arms [91]. In the neutral state

Mechanisms for radical reactions initiating from N-hydroxyphthalimide esters

• Carlos R. Azpilcueta-Nicolas and
• Jean-Philip Lumb

Beilstein J. Org. Chem. 2024, 20, 346–378, doi:10.3762/bjoc.20.35

• specific activation mechanism, both net reductive and redox neutral transformations can be implemented. Photocatalytic reductive quenching mechanism Among the most common reactions of NHPI esters are radical additions to electron-deficient olefins under net-reductive conditions, often referred to as Giese

• example, the NHPI ester derived from pivalic acid 58 and Hantzsch ester HE form EDA complex 59 which participates in radical mediated hydroalkylation reactions [60][61] (Scheme 13A). In the presence of electron deficient olefin 60, classic Giese-type addition takes place under photocatalyst-free

Tandem Hock and Friedel–Crafts reactions allowing an expedient synthesis of a cyclolignan-type scaffold

• Viktoria A. Ikonnikova,
• Cristina Cheibas,
• Oscar Gayraud,
• Alexandra E. Bosnidou,
• Nicolas Casaretto,
• Gilles Frison and
• Bastien Nay

Beilstein J. Org. Chem. 2024, 20, 162–169, doi:10.3762/bjoc.20.15

• -donor substituents, while highly electron-deficient substituents (CN, NO2) precluded the cyclization. Overall, this sequence led to valuable 1-aryltetralines structurally related to medicinally relevant cyclolignan natural products. X-ray crystallographic structure of product 6 (CCDC 2301977). The

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

• ) reactions involving diverse electron-rich alkynes and electron-deficient alkenes. In this review, a comprehensive investigation of the recent and noteworthy advancements in the research on push–pull chromophores prepared via the [2 + 2] CA–RE reaction is conducted. In particular, an overview of the

• optoelectronics) [1][2]. The synthesis of push–pull chromophores is often achieved through click-type reactions between electron-rich alkynes and electron-deficient alkenes, which is a reliable and atom-economical method. Diverse chromophores can be obtained via this method, depending upon the choice of alkynes

• properties of push–pull chromophores remain fragmented. Thus, the primary objective of this review is to consolidate the developments in the research on push–pull chromophores prepared via [2 + 2] CA–RE reactions between electron-rich alkynes and electron-deficient alkenes across various domains of chemistry

Using the phospha-Michael reaction for making phosphonium phenolate zwitterions

• Matthias R. Steiner,
• Max Schmallegger,
• Larissa Donner,
• Johann A. Hlina,
• Christoph Marschner,
• Judith Baumgartner and
• Christian Slugovc

Beilstein J. Org. Chem. 2024, 20, 41–51, doi:10.3762/bjoc.20.6

• the mentioned reactions, the first step of the catalytic cycle is the nucleophilic attack of the phosphine on the electrophile, in many cases an electron-deficient olefin. The zwitterion formed from this conjugate addition can subsequently act as a nucleophile or as a base [3][4][5]. The efficiency of

Anion–π catalysis on carbon allotropes

• M. Ángeles Gutiérrez López,
• Mei-Ling Tan,
• Giacomo Renno,
• Augustina Jozeliūnaitė,
• J. Jonathan Nué-Martinez,
• Javier Lopez-Andarias,
• Naomi Sakai and
• Stefan Matile

Beilstein J. Org. Chem. 2023, 19, 1881–1894, doi:10.3762/bjoc.19.140

• catalysis; electromicrofluidics; enolate addition; ether cyclizations; fullerenes; Introduction Anion–π catalysis was introduced ten years ago [1]. The idea is to stabilize anionic transition states on electron-deficient, π-acidic aromatic surfaces (Figure 1A). The true beginning is arguably in 2015

• monomer 22 much less significantly. With less electron-deficient NDIs carrying two sulfide donors in the core, the catalytic activity of 45 dropped below that of fullerene monomer 22. Oxidation of the sulfide donors into sulfoxide acceptors increased the catalytic activity much less than expected, resting

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

• , the third carbon allotrope, have unique spherical molecular structures and exhibit high reactivity as electron-deficient polyolefins. The excellent redox properties of fullerenes are useful for their chemical derivatization and practical applications [1][2][3][4][5]. Fullerene anions can be easily

Substituent-controlled construction of A₄B₂-hexaphyrins and A₃B-porphyrins: a mechanistic evaluation

• Seda Cinar,
• Dilek Isik Tasgin and
• Canan Unaleroglu

Beilstein J. Org. Chem. 2023, 19, 1832–1840, doi:10.3762/bjoc.19.135

• with electron-deficient tripyrrane 5. Supporting Information Supporting Information File 8: Analytical data and copies of spectra. Acknowledgements The presented work is a part of the Ph.D. thesis entitled “Synthesis of Porphyrins and Expanded Porphyrins from Oligopyrrolic Compounds and Investigatıon

Synthetic approach to 2-alkyl-4-quinolones and 2-alkyl-4-quinolone-3-carboxamides based on common β-keto amide precursors

• Yordanka Mollova-Sapundzhieva,
• Plamen Angelov,
• Danail Georgiev and
• Pavel Yanev

Beilstein J. Org. Chem. 2023, 19, 1804–1810, doi:10.3762/bjoc.19.132

• -mediated domino reaction of chromone-3-carboxaldehydes and amines [41], Pd-catalyzed redox-neutral C–N coupling reaction of iminoquinones with electron-deficient alkenes [42], NH3 insertion into o‑haloarylynones [43], gold(III)-catalyzed azide-yne cyclization [44], Michael/Truce-Smiles rearrangement

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

• modification, the study by Zhou et al. showcases the importance of solvent choice and annealing techniques in optimizing the performance of all-PSCs using Qx9 and Qx10. While both polymers served as donors in all-PSC devices, the study primarily focused on side chain engineering of the electron-deficient Qx

• a new class of FREAs called Y6. Y6 utilizes a ladder-type electron-deficient core-based central fused ring (dithienothiophen[3.2-b]pyrrolobenzothiadiazole) and achieved a remarkable efficiency of 16% in OSCs [26]. Building upon this breakthrough, Liu et al. blended Y6 with their polymer D18

A deep-red fluorophore based on naphthothiadiazole as emitter with hybridized local and charge transfer and ambipolar transporting properties for electroluminescent devices

• Suangsiri Arunlimsawat,
• Patteera Funchien,
• Pongsakorn Chasing,
• Atthapon Saenubol,
• Taweesak Sudyoadsuk and
• Vinich Promarak

Beilstein J. Org. Chem. 2023, 19, 1664–1676, doi:10.3762/bjoc.19.122

• energy gap between HOMO/LUMO hybrid orbits and drive fluorescence emission to longer wavelengths [48][49]. In this molecular design, the strong electron-deficient naphtho[2,3-c][1,2,5]thiadiazole (Nz) [13][50][51] as an acceptor and the strong electron-donating carbazole [52] as a donor unit were used in

• behavior in the potential window from −1.5 eV to 2.0 eV. The reduction wave appeared at a half-wave potential (E1/2) of −1.26 eV assigned to the reduction of an electron-deficient Nz core as observed in the calculated LUMO orbital [39]. The first oxidation wave occurred at E1/2 of 1.05 eV and was ascribed

Lewis acid-promoted direct synthesis of isoxazole derivatives

• Dengxu Qiu,
• Chenhui Jiang,
• Pan Gao and
• Yu Yuan

Beilstein J. Org. Chem. 2023, 19, 1562–1567, doi:10.3762/bjoc.19.113

• 11). With the optimal reaction conditions in hand, various alkynes were examined as dipolarophiles (Scheme 2). A range of functional groups were tolerated in this reaction, such as alkyl, methoxy, halo, and heterocycles. It was found that electron-deficient groups in the phenyl ring (3g–i) were more

• good yields (Scheme 3). It was observed that 2-methylquinoline with electron-deficient functional groups afforded the corresponding products in excellent yields of up to 92% (4a–c). Likewise, 2-methylquinoline substituted with electron-rich functional groups were suitable substrates and achieved good

N-Sulfenylsuccinimide/phthalimide: an alternative sulfenylating reagent in organic transformations

• Fatemeh Doraghi,
• Seyedeh Pegah Aledavoud,
• Mehdi Ghanbarlou,
• Bagher Larijani and
• Mohammad Mahdavi

Beilstein J. Org. Chem. 2023, 19, 1471–1502, doi:10.3762/bjoc.19.106

• an effective catalysis system (Scheme 29) [63]. Kinetic studies in this cross coupling-reaction indicated that N-(arylthio)succinimides 1 with electron-deficient arene 4 undergoe thioarylation catalyzed by Fe(NTf2)3. Related molecules bearing an electron-rich arene showed an autocatalytic pathway

Application of N-heterocyclic carbene–Cu(I) complexes as catalysts in organic synthesis: a review

• Nosheen Beig,
• Varsha Goyal and
• Raj K. Bansal

Beilstein J. Org. Chem. 2023, 19, 1408–1442, doi:10.3762/bjoc.19.102

• alkenylate a variety of electron-rich as well as electron-deficient (hetero)arenes. Of the three imidazolylidene derived NHC–CuCl catalysts, the best results (up to 94% yield) were obtained with [(IiPr)CuCl]. The method has several key features, such as mild reaction conditions, tolerance of various

Organic thermally activated delayed fluorescence material with strained benzoguanidine donor

• Alexander C. Brannan,
• Elvie F. P. Beaumont,
• Nguyen Le Phuoc,
• George F. S. Whitehead,
• Mikko Linnolahti and
• Alexander S. Romanov

Beilstein J. Org. Chem. 2023, 19, 1289–1298, doi:10.3762/bjoc.19.95

• compared with the 4CzIPN corroborates with the electron deficient nature of the benzoguanidine moiety thus making it harder to oxidize compared with the more electron-rich carbazole moiety. This results in stabilization of the HOMO energy level at −6.4 eV for 4BGIPN. Significant stabilization for both HOMO

Non-noble metal-catalyzed cross-dehydrogenation coupling (CDC) involving ether α-C(sp³)–H to construct C–C bonds

• Hui Yu and
• Feng Xu

Beilstein J. Org. Chem. 2023, 19, 1259–1288, doi:10.3762/bjoc.19.94

• electron-deficient position of the pyridine ring in complex B to obtain pyridine radical C, which aromatizes through tert-butoxyl radical-mediated extraction of hydrogen to afford the desired 2-substituted pyridine and regenerate Sc(OTf)3. In 2019, Liu et al. first reported an enantioselective CDC of

Photoredox catalysis harvesting multiple photon or electrochemical energies

• Mattia Lepori,
• Simon Schmid and
• Joshua P. Barham

Beilstein J. Org. Chem. 2023, 19, 1055–1145, doi:10.3762/bjoc.19.81

• ). Nucleophilic addition of the amine to the acyl radical and amine-assisted intermolecular proton transfer [84] generates the α-hydroxy radical 24 from which formation of the amide 25 proceeds either via i) oxidation by [Ir2]+ and deprotonation or ii) radical chain propagation [85]. Electron-deficient, electron

The unique reactivity of 5,6-unsubstituted 1,4-dihydropyridine in the Huisgen 1,4-diploar cycloaddition and formal [2 + 2] cycloaddition

• Xiu-Yu Chen,
• Hui Zheng,
• Ying Han,
• Jing Sun and
• Chao-Guo Yan

Beilstein J. Org. Chem. 2023, 19, 982–990, doi:10.3762/bjoc.19.73

• ]. The well-known Huisgen 1,4-dipoles have a special kind of zwitterionic intermediates and are usually prepared by a nucleophilic addition of pyridine, quinoline, isoquinoline and other aza-arenes to electron-deficient alkynes [4][5][6][7][8]. The reactive Huisgen 1,4-dipoles have been widely employed

• ][59][60][61][62][63][64], herein, we wish to report the use of 5,6-unsubstituted 1,4-dihydropyridines as electron-deficient alkenes in the Huisgen 1,4-diploar cycloaddition and as electron-rich alkenes in formal [2 + 2] cycloadditions for the efficient synthesis of isoquinolino[1,2-f][1,6

• unprecedented synthetic reactivity of the electron-deficient alkynes, but also provides efficient synthetic methodologies for complex nitrogen-containing heterocycles. The potential application of this reaction in organic synthesis and medicinal chemistry might be significant. Experimental General procedure for