[3 + 2] Cycloaddition of thioformylium methylide with various arylidene-azolones in the synthesis of 7-thia-3-azaspiro[4.4]nonan-4-ones

• Daniil I. Rudik,
• Irina V. Tiushina,
• Anatoly I. Sokolov,
• Alexander Yu. Smirnov,
• Alexander R. Romanenko,
• Alexander A. Korlyukov,
• Andrey A. Mikhaylov and
• Mikhail S. Baranov

Beilstein J. Org. Chem. 2025, 21, 1791–1798, doi:10.3762/bjoc.21.141

• , proved to be a more promising derivatization approach (Scheme 4). Thus, the short-term action of hydrogen peroxide successfully converted compounds 7e, 7c, and 9e to their corresponding sulfoxides 11e, 11c, and 13e. However, prolonged oxidation led not only to sulfone formation but also to deeper

Research progress on calixarene/pillararene-based controlled drug release systems

• Liu-Huan Yi,
• Jian Qin,
• Si-Ran Lu,
• Liu-Pan Yang,
• Li-Li Wang and
• Huan Yao

Beilstein J. Org. Chem. 2025, 21, 1757–1785, doi:10.3762/bjoc.21.139

Oxetanes: formation, reactivity and total syntheses of natural products

• Peter Gabko,
• Martin Kalník and
• Maroš Bella

Beilstein J. Org. Chem. 2025, 21, 1324–1373, doi:10.3762/bjoc.21.101

Recent advances in oxidative radical difunctionalization of N-arylacrylamides enabled by carbon radical reagents

• Jiangfei Chen,
• Yi-Lin Qu,
• Ming Yuan,
• Xiang-Mei Wu,
• Heng-Pei Jiang,
• Ying Fu and
• Shengrong Guo

Beilstein J. Org. Chem. 2025, 21, 1207–1271, doi:10.3762/bjoc.21.98

• a specific focus on strategies involving carbon-centered radicals. The reactions are systematically categorized according to their initiation modes and radical sources, including (1) transition-metal-catalyzed radical reactions, (2) peroxide-mediated thermal processes, (3) photoredox-catalyzed

• -/trifluoroalkylation reagents, α-carbonyl alkyl bromides/alcohols, alkyl halides, and alkyl carboxylic acids, have been successfully applied to this transformation to afford 3-substituted indolin-2-ones. In 2013, Li’s group reported a novel DTBP(di-tert-butyl peroxide)-mediated oxidative 1,2-alkylarylation of

• the alkyl source was presented, providing a novel and efficient route to 3,3-dialkylated oxindoles [7]. In this system, Cu2O was used as the catalyst, combined with dicumyl peroxide (DCP) as the oxidant, in ethyl acetate (EtOAc) at 120 °C under an argon atmosphere. This reaction efficiently produced

Beyond symmetric self-assembly and effective molarity: unlocking functional enzyme mimics with robust organic cages

• Keith G. Andrews

Beilstein J. Org. Chem. 2025, 21, 421–443, doi:10.3762/bjoc.21.30

• phosphodiesters by 105–107 by electrophilic activation of ester and nucleophilic activation of water or peroxide at the metal ion [101][102]. The takeaway message is that polarization is most effective when it is bifunctional. In enzymes, there is never just a nucleophile – there is always a metal, “oxyanion hole

Reactivity of hypervalent iodine(III) reagents bearing a benzylamine with sulfenate salts

• Beatriz Dedeiras,
• Catarina S. Caldeira,
• José C. Cunha,
• Clara S. B. Gomes and
• M. Manuel B. Marques

Beilstein J. Org. Chem. 2024, 20, 3281–3289, doi:10.3762/bjoc.20.272

• dimerize to yield peroxide. However, the instability of peroxide favors the predominance of radical oxygen species, which can react with the sulfur atom from sulfinamide 6 previously formed in the reaction medium (pathway A). Following the establishment of the new S–O bond, a radical reaction akin to retro

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

• to the vacant axial site of the metal centers. This binding is followed by reduction to either hydrogen peroxide (H2O2) via a two-electron (2e−) pathway, water (H2O) through a four-electron (4e−) pathway, or a combination of both products through a concerted transfer of electrons and protons [126

Advances in radical peroxidation with hydroperoxides

• Oleg V. Bityukov,
• Pavel Yu. Serdyuchenko,
• Andrey S. Kirillov,
• Gennady I. Nikishin,
• Vera A. Vil’ and
• Alexander O. Terent’ev

Beilstein J. Org. Chem. 2024, 20, 2959–3006, doi:10.3762/bjoc.20.249

• become sought-after functionalities, particularly following the multi-tone consumption in polymer production and success in medicinal chemistry. The selective introduction of a peroxide fragment at different positions on the target molecule is a priority in the modern reaction design. The pioneering

• growing urbanization, expanding infrastructure projects and industrialization. A wide range of organic peroxide initiators is now available (Scheme 1) and this is continually being expanded to meet the changing requirements of the polymer industry. Discovery of artemisinin, which was highlighted with the

• Nobel Prize, initiated a new era in organic peroxide chemistry. A large number of synthetic antimalarial peroxides have been prepared [3][4]. Further intensive research indicated that organic peroxides have antihelmintic, antiprotozoal, fungicidal, antiviral and other activities [5]. Therefore, the

Efficient modification of peroxydisulfate oxidation reactions of nitrogen-containing heterocycles 6-methyluracil and pyridine

• Alfiya R. Gimadieva,
• Yuliya Z. Khazimullina,
• Aigiza A. Gilimkhanova and
• Akhat G. Mustafin

Beilstein J. Org. Chem. 2024, 20, 2599–2607, doi:10.3762/bjoc.20.219

• in two different ways: with metallophthalocyanine catalysts present and by including hydrogen peroxide as a co-oxidant (Scheme 1). Metal–phthalocyanine complexes (PcM) are recognized as catalysts for gentle, particular oxidation reactions under aerobic [14] and H2O2-based conditions [15][16][17][18

• reactions was made. It has been suggested that a nucleophilic substitution of the peroxide oxygen atom occurs in peroxydisulfate [32]. Regarding phenols (Elbs reaction), there is also a nucleophilic substitution of the phenolate ion. For aromatic amines (Boyland–Sims reaction), a neutral nitrogen atom of

• peroxydisulfate ion, leading to the production of oxygen [39]: Oxygen accumulation is additionally achieved by hydrogen peroxide self-decay, which is known to be increased in alkaline conditions [40]: Additionally, it has been reported [41] that hydroxyl radicals, produced from the decomposition of H2O2, can

A review of recent advances in electrochemical and photoelectrochemical late-stage functionalization classified by anodic oxidation, cathodic reduction, and paired electrolysis

• Nian Li,
• Ruzal Sitdikov,
• Ajit Prabhakar Kale,
• Joost Steverlynck,
• Bo Li and
• Magnus Rueping

Beilstein J. Org. Chem. 2024, 20, 2500–2566, doi:10.3762/bjoc.20.214

• conditions. A comparison was made between the developed electrochemical conditions for each substrate and an analogous non-electrochemical method using peroxide for CF3 radical generation. In all cases, the electrochemical route delivered improved yields (Scheme 1). The Wang group later discovered a C(sp2)–H

• generated tert-butyl peroxide to form an allylic peroxide, which ultimately transforms into an enone upon elimination of t-BuOH (Scheme 24). One year later, they developed an electrochemical transformation closely related to their electrochemical allylic oxidation, i.e. the oxidation of unactivated C(sp3)–H

Efficacy of radical reactions of isocyanides with heteroatom radicals in organic synthesis

• Akiya Ogawa and
• Yuki Yamamoto

Beilstein J. Org. Chem. 2024, 20, 2114–2128, doi:10.3762/bjoc.20.182

• -isocyanobiphenyl with AIBN or dibenzoyl peroxide (DBP) affords 6-cyanoisopropyl- or 6-phenyl-substituted phenanthridine derivatives. When the reaction was performed in the presence of TTMSS and AIBN, 6-tris(trimethylsilyl)-substituted phenanthridine derivatives were mainly obtained (Scheme 21) [74]. Tobisu and

Multicomponent syntheses of pyrazoles via (3 + 2)-cyclocondensation and (3 + 2)-cycloaddition key steps

• Ignaz Betcke,
• Alissa C. Götzinger,
• Maryna M. Kornet and
• Thomas J. J. Müller

Beilstein J. Org. Chem. 2024, 20, 2024–2077, doi:10.3762/bjoc.20.178

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

• benzoyl peroxide, TEMPO, and the combination of alkyl halides with BEt3, were not applicable to this reaction. Physical properties The electronic absorption spectra of norcorrole 1 and adduct 2a are shown in Figure 3. While norcorrole 1 exhibited a weak absorption band from 600 nm to the NIR region, due

Syntheses and medicinal chemistry of spiro heterocyclic steroids

• Laura L. Romero-Hernández,
• Ana Isabel Ahuja-Casarín,
• Penélope Merino-Montiel,
• Sara Montiel-Smith,
• José Luis Vega-Báez and
• Jesús Sandoval-Ramírez

Beilstein J. Org. Chem. 2024, 20, 1713–1745, doi:10.3762/bjoc.20.152

• straightforward method to synthesize a series of steroidal spiro 1,2,4-triazolidin-3-ones 96 [52][53][54]. The spiro derivatives were selectively obtained as the unique isomers by reacting semicarbazones 95 with hydrogen peroxide at 0 °C. The reactions were conducted in chloroform, yielding all products in good

• yields (82–85%) (Scheme 28). The authors proposed a free radical mechanism facilitated by hydrogen peroxide, generating a primary radical at the terminal nitrogen atom -CO-HN• which then adds to the carbon atom of the imino group. The reaction mechanism was substantiated by theoretical calculations

• peroxide solution or a mixture of bis(trimethylsilyl)peroxide and trimethylsilyl trifluoromethanesulfonate. In any case, the spiro products were afforded as a mixture of diastereomers. Finally, tetraoxanes 167d and 168d were synthesized by basic hydrolysis of the methyl esters 167a and 168a (Scheme 43

Tetrabutylammonium iodide-catalyzed oxidative α-azidation of β-ketocarbonyl compounds using sodium azide

• Christopher Mairhofer,
• David Naderer and
• Mario Waser

Beilstein J. Org. Chem. 2024, 20, 1510–1517, doi:10.3762/bjoc.20.135

• peroxide catalyzed by tetrabutylammonium iodide (TBAI). By utilizing these readily available bulk chemicals a variety of cyclic β-ketocarbonyl derivatives can be efficiently α-azidated under operationally simple conditions. Control experiments support a mechanistic scenario involving in situ formation of

• conditions are best-suited. We have recently established the use of dibenzoyl peroxide (DBPO) as a very powerful oxidant for oxidative heterofunctionalization reactions using simple nucleophilic inorganic salts as heteroatom transfer reagents [39][41]. This was successfully demonstrated for the non-catalyzed

• powerful approaches to access valuable organic azides. In this contribution we report the direct α-azidation of cyclic β-ketocarbonyl compounds using NaN3. This coupling of two inherently nucleophilic species is possible by carrying out the reaction under oxidative conditions using dibenzoyl peroxide in

Cofactor-independent C–C bond cleavage reactions catalyzed by the AlpJ family of oxygenases in atypical angucycline biosynthesis

• Jinmin Gao,
• Liyuan Li,
• Shijie Shen,
• Guomin Ai,
• Bin Wang,
• Fang Guo,
• Tongjian Yang,
• Hui Han,
• Zhengren Xu,
• Guohui Pan and
• Keqiang Fan

Beilstein J. Org. Chem. 2024, 20, 1198–1206, doi:10.3762/bjoc.20.102

• deprotonation of 8 to form a substrate anion, which activated molecular oxygen to generate a substrate radical and the superoxide anion O2•−. The ensuing radical rebound reaction led to the formation of a peroxide intermediate, which in turn underwent a ring opening reaction to generate the hydroquinone

Light on the sustainable preparation of aryl-cored dibromides

• Fabrizio Roncaglia,
• Alberto Ughetti,
• Nicola Porcelli,
• Biagio Anderlini,
• Andrea Severini and
• Luca Rigamonti

Beilstein J. Org. Chem. 2024, 20, 1076–1087, doi:10.3762/bjoc.20.95

• suffer from the generation of stoichiometric amounts of byproducts and often encounter selectivity troubles. To mitigate these issues, we extended the greener peroxide-bromide halogenation method, initially developed for monobromides, to afford aryl-cored polybromides in high yields. The same method can

• radical initiator, such as azobisisobutyronitrile (AIBN) [31][32][33][34] or benzoyl peroxide [35][36]; substances affected by safety concerns on transportation, storage, and use. Moreover, the regeneration of the halogen comes at a cost: the release of stoichiometric amounts of succinimide, whose

• redox couple NaBr–NaBrO3 in acidic media [40][41]. Other variations include the system KBr–Oxone® [42]. However, based on a literature review, we concluded that unparalleled efficiency and sustainability can be achieved through the well-established redox equilibria between hydrogen peroxide and halide

Advancements in hydrochlorination of alkenes

• Daniel S. Müller

Beilstein J. Org. Chem. 2024, 20, 787–814, doi:10.3762/bjoc.20.72

• addition. Therefore, anti-Markovnikov products are generally not observed. b) In contrast to the reactions with HBr (peroxide effect) [31][32], the formation of anti-Markovnikov products is low even in the presence of peroxides or photochemical activation. For instance, Whitmore and co-workers observed

• only 10–25% of the primary chloride for the reaction of tert-butylethylene with HCl in the presence of benzoyl peroxide [33]. c) Several metal halides such as AlCl3, SnCl4, FeCl3, and CuCl exhibit catalytic activities for the hydrochlorination of alkenes. The enthalpy of formation for the hydrogen

Methodology for awakening the potential secondary metabolic capacity in actinomycetes

• Shun Saito and
• Midori A. Arai

Beilstein J. Org. Chem. 2024, 20, 753–766, doi:10.3762/bjoc.20.69

• ), which upon sensing ROS, release their repression and activate the expression of various genes [93][94][95]. Wei et al. reported that the production of validamycin A (25) by Streptomyces hygroscopicus 5008 could be activated at the transcriptional level by simply adding hydrogen peroxide (H2O2; which

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

• dithienonaphthalene products (e.g., 16) exhibit very different fluorescence properties, S-extrusion from thiophene-annelated thiepines was consequently exploited for peroxide sensing. Very recently, Zhou et al. reported the synthesis of S-doped phenanthrene and triphenylene derivatives via the thermally-induced ring

• dithienonaphthalenes, upon S-extrusion triggered by electrochemical oxidation. Bottom: Exploitation of the S-extrusion process for peroxide sensing, taking advantage of the lability of oxidized dithienobenzothiepine to generate highly fluorescent dithienonaphthalene [63]. Synthesis of S-doped extended triphenylene

Optimizations of lipid II synthesis: an essential glycolipid precursor in bacterial cell wall synthesis and a validated antibiotic target

• Milandip Karak,
• Cian R. Cloonan,
• Brad R. Baker,
• Rachel V. K. Cochrane and
• Stephen A. Cochrane

Beilstein J. Org. Chem. 2024, 20, 220–227, doi:10.3762/bjoc.20.22

• -phosphite intermediate was then oxidized with hydrogen peroxide to yield dibenzyl α-phosphate 6, achieving an overall yield of 89% for these two steps. Removal of the 2-(phenylsulfonyl)ethanol protecting group in compound 6 was successfully achieved through treatment with 1,8-diazabicyclo[5.4.0]undec-7-ene

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

• the photocatalytic production of H2 while the nanospheres produced hydrogen peroxide (H2O2). The introduction of the additional carbazolylphenyl moiety in the CPC molecule [4] allowed us to improve the EQEmax of an OLED to 25% [7]. In continuation of our studies in the field of the development of new

Radical chemistry in polymer science: an overview and recent advances

• Zixiao Wang,
• Feichen Cui,
• Yang Sui and
• Jiajun Yan

Beilstein J. Org. Chem. 2023, 19, 1580–1603, doi:10.3762/bjoc.19.116

• successful nitroxide-mediated polymerization (NMP). In 1993, Georges et al. used benzoyl peroxide (BPO) as the initiator and 2,2,6,6-tetramethyl-1-piperidinyloxyl (TEMPO) as the control agent. It was called a bicomponent initiating system containing both stable free nitroxide and a conventional thermal

• technique requires radical generation on the polymer backbone. A typical approach involves hydrogen abstraction by organic oxidants such as oxygen radicals from peroxide initiators [114], which is similar to the radical crosslinking process, vide infra. Radicals may also be generated thermally, through

• initiator is needed to start the radical crosslinking. Besides sulfur, peroxides such as di-tert-butylcumyl peroxide (BCUP) and dicumyl peroxide (DCP) are often used in radical crosslinking. Free radicals are generated at the peroxides’ decomposition temperature and attack the polymer chains to achieve

Cyclodextrins permeabilize DPPC liposome membranes: a focus on cholesterol content, cyclodextrin type, and concentration

• Ghenwa Nasr,
• Hélène Greige-Gerges,
• Sophie Fourmentin,
• Abdelhamid Elaissari and
• Nathalie Khreich

Beilstein J. Org. Chem. 2023, 19, 1570–1579, doi:10.3762/bjoc.19.115

• . Triton X-100, sodium chloride (NaCl), and Sephadex G25 gel were purchased from Sigma-Aldrich, Belgium. Ammonium molybdate, hydrogen peroxide, potassium dihydrogen phosphate, sodium sulfite, sodium bisulfite, chloroform, and methanol were purchased from Sigma-Aldrich, Germany. Cholesterol and

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

• of the product, while benzoyl peroxide (BPO) gave a low yield. Various nucleophiles 161, including ammonia, alkylamines, hydrazines, alcohols and alkoxides, indole, N-alkylpyrrole, N-substituted anilines, PhSH, and PhMgBr worked well under these conditions. Asymmetric thiolation of 4-substituted