Synthesis of β-ketophosphonates through aerobic copper(II)-mediated phosphorylation of enol acetates

• Alexander S. Budnikov,
• Igor B. Krylov,
• Fedor K. Monin,
• Valentina M. Merkulova,
• Alexey I. Ilovaisky,
• Liu Yan,
• Bing Yu and
• Alexander O. Terent’ev

Beilstein J. Org. Chem. 2025, 21, 1192–1200, doi:10.3762/bjoc.21.96

• -centered radical from diisopropyl H-phosphonate (2a). In addition, the anion affects the redox properties of the copper ion, and thus the optimal choice is important to achieve both sufficient oxidative properties and catalyst recycling by reoxidation with O2. The employment of Mn(acac)3 and FeCl3, which

Study of tribenzo[b,d,f]azepine as donor in D–A photocatalysts

• Katy Medrano-Uribe,
• Jorge Humbrías-Martín and
• Luca Dell’Amico

Beilstein J. Org. Chem. 2025, 21, 935–944, doi:10.3762/bjoc.21.76

• diverse scaffolds have been reported in the literature, the identification and use of novel PCs with tunable and diverse optical and redox properties can pave the way to uncharted reactivity. In this context, sulfur-based cores, widely used as acceptors in photoelectric materials [9][10][11][12][13][14

• which the HOMO orbital is not delocalized in one of the aromatic rings of the acceptor core. Redox properties analysis We started our analysis by looking at the impact of the diverse sulfur-based cores on the redox properties. Here, we can observe similar Eox values ranging from 1.41 V to 1.46 V vs SCE

• compound 5a with the other family members utilizing the same dehalogenation manifold. Here, even slightly changes in the redox properties have an influence on the yield of the reaction. The D–A with the azepine analog (5b), gave the dehalogenated product 8 in 58% NMR yield (Table 2, entry 2). Quite

Red light excitation: illuminating photocatalysis in a new spectrum

• Lucas Fortier,
• Corentin Lefebvre and
• Norbert Hoffmann

Beilstein J. Org. Chem. 2025, 21, 296–326, doi:10.3762/bjoc.21.22

• findings suggest that cyanins, specifically tailored to absorb in the NIR region, exhibit promising redox properties for applications in organic synthesis. A recent work by Goddard et al. has demonstrated that compound 46 is highly effective in various photoredox transformations, such as aza-Henry

• redox properties similar to those of squaraine derivatives, enabling key transformations such as the cyclization of anilines with maleimides and the reduction of Umemoto salts for trifluoromethylation of alkenes. With an excited-state reduction potential around 0.80 V, 46 demonstrates the capability to

• redox properties (Figure 12). Cyanins with electron-donating groups (e.g., 49 and 50) are less oxidizing, with cathodically shifted reduction potentials compared to the unsubstituted 46. In contrast, cyanins with electron-withdrawing groups (e.g., 51 and 52) show anodically shifted reduction peaks

Advances in the use of metal-free tetrapyrrolic macrocycles as catalysts

• Mandeep K. Chahal

Beilstein J. Org. Chem. 2024, 20, 3085–3112, doi:10.3762/bjoc.20.257

• photocatalysts. The results demonstrated that these substituents significantly influenced the redox properties of the porphyrins, yielding up to 86% with the electron-poor meso-tetrakis(pentafluorophenyl)porphyrin (67), compared to H2TPP and other electron-rich systems. This finding indicated that fine-tuning

Synthesis, electrochemical properties, and antioxidant activity of sterically hindered catechols with 1,3,4-oxadiazole, 1,2,4-triazole, thiazole or pyridine fragments

• Daria A. Burmistrova,
• Andrey Galustyan,
• Nadezhda P. Pomortseva,
• Kristina D. Pashaeva,
• Maxim V. Arsenyev,
• Oleg P. Demidov,
• Mikhail A. Kiskin,
• Andrey I. Poddel’sky,
• Nadezhda T. Berberova and
• Ivan V. Smolyaninov

Beilstein J. Org. Chem. 2024, 20, 2378–2391, doi:10.3762/bjoc.20.202

• ) < 1,3,4-oxadiazole derivatives (1.37–1.39 V). The redox properties of catechols 1–9 were studied by cyclic voltammetry (CV) (Table 1). In the anodic area, the electrochemical profile for catechol thioethers 1–5 represents two successive irreversible oxidative stages. The first two-electron peak is

Radical reactivity of antiaromatic Ni(II) norcorroles with azo radical initiators

• Siham Asyiqin Shafie,
• Ryo Nozawa,
• Hideaki Takano and
• Hiroshi Shinokubo

Beilstein J. Org. Chem. 2024, 20, 1967–1972, doi:10.3762/bjoc.20.172

• physical properties, such as reversible redox properties [4][5] and stacked-ring aromaticity [6][7][8][9][10]. While Ni(II) norcorroles are stable under ambient conditions despite the distinct 16π-antiaromaticity, they show unique reactivities with various reagents due to the high-lying HOMO and low-lying

SOMOphilic alkyne vs radical-polar crossover approaches: The full story of the azido-alkynylation of alkenes

• Julien Borrel and
• Jerome Waser

Beilstein J. Org. Chem. 2024, 20, 701–713, doi:10.3762/bjoc.20.64

• the development of the azidobenziodazolone scaffold [17]. This class of derivative showed an improved safety profile while retaining the redox properties of the original reagent. A single example of azido-alkynylation has been reported by Ramasastry and co-workers during a mechanistic study for an

Enhanced reactivity of Li⁺@C₆₀ toward thermal [2 + 2] cycloaddition by encapsulated Li⁺ Lewis acid

• Hiroshi Ueno,
• Yu Yamazaki,
• Hiroshi Okada,
• Fuminori Misaizu,
• Ken Kokubo and
• Hidehiro Sakurai

Beilstein J. Org. Chem. 2024, 20, 653–660, doi:10.3762/bjoc.20.58

• reasons for the irreversible redox properties after the second reduction process have not been thoroughly investigated, the observed phenomena could potentially be attributed to ring opening or simple decomposition under the conditions. From these results, the LUMO levels of the compounds were estimated

Enhanced host–guest interaction between [10]cycloparaphenylene ([10]CPP) and [5]CPP by cationic charges

• Eiichi Kayahara,
• Yoshiyuki Mizuhata and
• Shigeru Yamago

Beilstein J. Org. Chem. 2024, 20, 436–444, doi:10.3762/bjoc.20.38

• new CPP analogs [4][5][6][7][8] and unveiling their unique physical properties, such as size-dependent photophysical [9][10][11][12][13][14][15] and redox properties [16][17][18][19][20][21]. The other, and one of the most exciting, functions of CPPs derived from the ring structure is their host

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

•  26B). A novel approach for the activation of redox-active esters was recently reported by Cornella and co-workers [32]. In this study, low valent bismuth (Bi) complex Bi-1 was found to exhibit redox properties similar to those of first row-transition metal catalysts, enabling the activation of

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

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

• expanded by pyrrolo annelation. The optical and redox properties of these compounds, in some cases carbon-rich, were studied by UV–vis absorption spectroscopy and cyclic voltammetry. Synthetically, the work explores IF diones or fluorenone as central building blocks by subjecting the carbonyl groups to a

• +) containing two 6π-aromatic 1,3-dithiolium rings. The redox properties and geometries of the redox states have been finely tuned by extending the conjugated system with various cores, such as polycyclic aromatic hydrocarbons (PAHs), resulting in so-called extended TTFs [9][10][11][12]. One example of this is

• -electron reductions at −1.63 V and −1.89 V, indicating that the larger conjugated system of compound 27 does not significantly change the redox properties of the compound. Compounds 26 and 27 lack the DTF donor part and are hence oxidized at significantly higher potentials than the other compounds. On the

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

• , University of Tsukuba, Ibaraki 305-8577, Japan Department of Theoretical Studies, Institute for Molecular Science, Okazaki 444-8585, Japan 10.3762/bjoc.19.138 Abstract Endohedral metallofullerenes have excellent redox properties, which can be used to vary their reactivity to certain classes of molecules

• , 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

Selectivity control towards CO versus H₂ for photo-driven CO₂ reduction with a novel Co(II) catalyst

• Lisa-Lou Gracia,
• Philip Henkel,
• Olaf Fuhr and
• Claudia Bizzarri

Beilstein J. Org. Chem. 2023, 19, 1766–1775, doi:10.3762/bjoc.19.129

• developing the major components of a photocatalytic system for CO2 reduction, such as the photosensitizer (PS), the catalyst, and the sacrificial electron donor (SeD). Nevertheless, the solvent and eventual additives play an important role too [6], as they can influence the (photo)redox properties of the

• Supporting Information File 1). The redox properties of 1 were investigated using cyclic voltammetry in a DMA solution with 0.1 M tetrabutylammonium hexafluorophosphate (TBAPF6) as the supporting electrolyte (Table 1). The concentration of the analyte was 5 mM. Only the cathodic scan resulted in a rich

Synthesis, structure, and properties of switchable cross-conjugated 1,4-diaryl-1,3-butadiynes based on 1,8-bis(dimethylamino)naphthalene

• Semyon V. Tsybulin,
• Ekaterina A. Filatova,
• Alexander F. Pozharskii,
• Valery A. Ozeryanskii and
• Anna V. Gulevskaya

Beilstein J. Org. Chem. 2023, 19, 674–686, doi:10.3762/bjoc.19.49

• packing of almost linear molecules (Figure S69, Supporting Information File 1). UV–vis spectra and redox properties As stated above, oligomers 5 are cross-conjugated π-systems. For cross-conjugated structures, the main question is about the preferential conjugation path. For oligomers 5, two different

• to its analogs with electron-withdrawing substituents. The redox properties of oligomers 5 were evaluated by cyclic voltammetry (CV) in dichloromethane solution containing 0.1 M n-Bu4NPF6 in the standard three-electrode electrochemical cell: glassy carbon working electrode, platinum auxiliary

Redox-active molecules as organocatalysts for selective oxidative transformations – an unperceived organocatalysis field

• Elena R. Lopat’eva,
• Igor B. Krylov,
• Dmitry A. Lapshin and
• Alexander O. Terent’ev

Beilstein J. Org. Chem. 2022, 18, 1672–1695, doi:10.3762/bjoc.18.179

• -organocatalyzed”. Within this section, two process types can be distinguished. In one an organocatalyst molecule is not reduced or oxidized itself but facilitates a reaction by activating the redox properties of reactants (Scheme 1, type II). In such processes the basic principles and organocatalyst structures

• properties of reagents In this section we demonstrate examples of the main types of oxidative processes, in which an organocatalyst does not behave as a redox-active molecule itself but interacts with substrates and thus modulates their redox properties (Scheme 1, type II organocatalysis). Secondary amines

• , organocatalysis by the modulation of redox properties of reagents has much in common with redox-neutral organocatalysis. With the exception of free-radical processes, the distinguishing feature of these organocatalyzed oxidations frequently lies in the involvement of peroxides as O-nucleophiles or O-electrophiles

Molecular and macromolecular electrochemistry: synthesis, mechanism, and redox properties

• Shinsuke Inagi and
• Mahito Atobe

Beilstein J. Org. Chem. 2022, 18, 1505–1506, doi:10.3762/bjoc.18.158

• macromolecular electrochemistry. The scope of this interdisciplinary issue ranges from synthetic aspects (such as electrosynthesis and reaction mechanisms) to materials science (including redox properties and devices). Shinsuke Inagi and Mahito Atobe Yokohama, October 2022

Synthesis and electrochemical properties of 3,4,5-tris(chlorophenyl)-1,2-diphosphaferrocenes

• Almaz A. Zagidullin,
• Farida F. Akhmatkhanova,
• Mikhail N. Khrizanforov,
• Robert R. Fayzullin,
• Tatiana P. Gerasimova,
• Ilya A. Bezkishko and
• Vasili A. Miluykov

Beilstein J. Org. Chem. 2022, 18, 1338–1345, doi:10.3762/bjoc.18.139

• )phosphonium bromides 6. Synthesis of 3,4,5-tris(chlorophenyl)-1,2-diphosphacyclopentadienides 7 and 3,4,5-tris(chlorophenyl)-1,2-diphosphaferrocenes 8. Electrochemical data for the redox properties of 3,4,5-triaryl-1,2-diphosphaferrocenes 8b and 8c. Supporting Information Supporting Information File 290

Synthesis, optical and electrochemical properties of (D–π)₂-type and (D–π)₂Ph-type fluorescent dyes

• Kosuke Takemura,
• Kazuki Ohira,
• Taiki Higashino,
• Keiichi Imato and
• Yousuke Ooyama

Beilstein J. Org. Chem. 2022, 18, 1047–1054, doi:10.3762/bjoc.18.106

• band, but also intense fluorescence emission both in solution and the solid state. Keywords: (D–π)2 structure; fluorescence; fluorescent dyes; photoabsorption; redox properties; Introduction The design and development of a new type of organic fluorescent dyes have been of considerable scientific and

Annulation of a 1,3-dithiole ring to a sterically hindered o-quinone core. Novel ditopic redox-active ligands

• Sergey V. Norkov,
• Anton V. Cherkasov,
• Andrey S. Shavyrin,
• Maxim V. Arsenyev,
• Viacheslav A. Kuropatov and
• Vladimir K. Cherkasov

Beilstein J. Org. Chem. 2021, 17, 273–282, doi:10.3762/bjoc.17.26

• ligand; 1,3-dithiole; ditopic ligand; o-quinone; thiete; Introduction There are a number of methods which may be used for the synthesis of new o-quinones in order to vary their redox properties and coordination abilities. The key features of o-quinones are redox activity as well as chelating

Synthesis and characterization of S,N-heterotetracenes

• Astrid Vogt,
• Florian Henne,
• Christoph Wetzel,
• Elena Mena-Osteritz and
• Peter Bäuerle

Beilstein J. Org. Chem. 2020, 16, 2636–2644, doi:10.3762/bjoc.16.214

• are shifted down-field (Hα 7.67, Hß 7.49 ppm) compared to SN4 13. MALDI–HRMS of all synthesized S,N-heteroacenes showed only a single peak for the molecular ions accounting for their purity. Optical and redox properties of S,N-heteroacenes 9, 13, 19, 22, and 33 in comparison to tetrathienoacene (TTA

• planar and conformationally restricted systems [48]. In order to get information about the redox properties and energetics of the frontier orbitals, the S,N-heteroacenes were studied by cyclic voltammetry and all potentials were referenced against the ferrocene/ferricenium couple (Table 1). In the series

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

• potential of tailor-made redox-active crown ethers for the development of new molecular switches. Yet, a careful design of tailor-made redox-active crown ethers is of great importance for tuning the crown ether binding and redox properties to achieve the desired molecular structure and switching mode, which

• between the two TTF2+ units. The addition of A1·PF6 does not have any impact on the redox properties of bisTTFC8, as hardly any pseudo[2]rotaxane forms with this axle. The NDI-decorated wheels NDIC8 and NDIC7 undergo two reversible reduction processes (E1/2red1, NDI→NDI•− and E1/2red2, NDI•−→NDI2−). Here

• in TTFC8 and TTFC7, the binding properties are altered significantly. The redox properties do not depend much on the crown ether core, irrespective of whether the redox-active unit is attached in a remote position or incorporated in the crown ether. Our findings provide some guidelines for how the

Recent developments in enantioselective photocatalysis

• Callum Prentice,
• James Morrisson,
• Andrew D. Smith and
• Eli Zysman-Colman

Beilstein J. Org. Chem. 2020, 16, 2363–2441, doi:10.3762/bjoc.16.197

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

• furnish compound 132 (Scheme 34). Since polyanilines are interesting π-conjugated polymers that contain characteristic conductivity by acid doping, environmental stability, optical and redox properties. Therefore, bridging of oligoaniline as a spacer between the functional units can lead toward the

Five-component, one-pot synthesis of an electroactive rotaxane comprising a bisferrocene macrocycle

• Natalie Lagesse,
• Luca Pisciottani,
• Maxime Douarre,
• Pascale Godard,
• Brice Kauffmann,
• Vicente Martí-Centelles and
• Nathan D. McClenaghan

Beilstein J. Org. Chem. 2020, 16, 1564–1571, doi:10.3762/bjoc.16.128

• was E1/2 = +0.380 V vs SCE showing that rotaxane 1a retained the redox properties of the parent ferrocene [21][22]. Importantly, the full reversibility of the one electron oxidation–reduction process attested to the stability of the electroactive system. Solid-state X-ray structure The solid-state