On the photoluminescence in triarylmethyl-centered mono-, di-, and multiradicals

• Daniel Straub,
• Markus Gross,
• Mona E. Arnold,
• Julia Zolg and
• Alexander J. C. Kuehne

Beilstein J. Org. Chem. 2025, 21, 964–998, doi:10.3762/bjoc.21.80

• , there are no reports on substantial photoluminescence, nor are there concepts to increase the ϕ in such systems, despite the many examples of highly emissive donor-substituted PTM- and TTM-based mono-radicals. In this overview, we will focus on reviewing the different hypotheses for the mechanisms

• mechanisms and reasons behind the fluorescence color and the fluorescence quantum yield and derive structure–optical property relationships. We will provide the reader with an overview of the perspectives and challenges of open-shell light-emitting radicals and discuss what to do to solve the remaining

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

• results are comparable to those obtained by the same author using the well-established PCs 1 and 3 (Table 3, entries 6 and 7) Next, we wanted to analyze the use of the PCs in reductive quenching mechanisms. For this purpose, we selected the Giese-type addition between the N-Cbz-Pro (12, Eox = 0.95 V vs

Recent advances in controllable/divergent synthesis

• Jilei Cao,
• Leiyang Bai and
• Xuefeng Jiang

Beilstein J. Org. Chem. 2025, 21, 890–914, doi:10.3762/bjoc.21.73

• literatures focusing on key regulatory factors for product divergent formation, in which controlling chemical selectivity primarily relies on ligands, metal catalysts, solvents, time, temperature, acids/bases, and subtle modifications of substrates. To gain a deeper understanding of the mechanisms underlying

• reaction activity and selectivity differentiation, the review provides a systematic analysis of the mechanisms of critical steps through specific case studies. It is hoped that the controllable/divergent synthesis concept will spark the interest of practitioners and aficionados to delve deeper into the

• substrates, both dicarbonylation and monocarbonylation processes occurred simultaneously with Cu(OAc)2, favoring the dicarbonylation process. In contrast, using CuBr(Me2S) the monocarbonylation process was favored. Possible reaction mechanisms: First, CO coordinates with copper salts to form (carbonyl)copper

Unraveling cooperative interactions between complexed ions in dual-host strategy for cesium salt separation

• Zhihua Liu,
• Ya-Zhi Chen,
• Ji Wang,
• Qingling Nie,
• Wei Zhao and
• Biao Wu

Beilstein J. Org. Chem. 2025, 21, 845–853, doi:10.3762/bjoc.21.68

• carbonyl (C=O) groups, as well as direct ion-pairing interactions between 18-crown-6-complexed Cs+ and hexaurea-bound PO43−. Single-crystal structural analysis corroborates these interactions, shedding light on the underlying mechanisms and providing valuable guidance for the rational design of advanced

Substituent effects in N-acetylated phenylazopyrazole photoswitches

• Radek Tovtik,
• Dennis Marzin,
• Pia Weigel,
• Stefano Crespi and
• Nadja A. Simeth

Beilstein J. Org. Chem. 2025, 21, 830–838, doi:10.3762/bjoc.21.66

• . For example, for NH-PAP-CF3 we observed that the ΦE→Z has a value of 25%, for NMe-PAP-CF3 27%, while for NAc-PAP-CF3 we observed an increase of ΦE→Z to 69%. Thermal half-lifes The metastable Z isomers can be converted back to the thermodynamically favored E form by thermal means. Four mechanisms were

• NAc-PAP-H and -Me), even surpassing the effects of methylation. Hammett analysis showed that the thermal population of the triplet state seem to be preferred as the thermal relaxation mechanisms of the back isomerization. EWGs and EDGs accelerated the relaxation dynamics compared to NAc-PAP-H

Origami with small molecules: exploiting the C–F bond as a conformational tool

• Patrick Ryan,
• Ramsha Iftikhar and
• Luke Hunter

Beilstein J. Org. Chem. 2025, 21, 680–716, doi:10.3762/bjoc.21.54

Photocatalyzed elaboration of antibody-based bioconjugates

• Marine Le Stum,
• Eugénie Romero and
• Gary A. Molander

Beilstein J. Org. Chem. 2025, 21, 616–629, doi:10.3762/bjoc.21.49

• catalysts, including photoredox catalysts, energy-transfer catalysts, and genetically encoded photocatalysts, highlighting their distinct features, mechanisms, applications, and prospects [41]. This thorough analysis showcased the promising advancements in the chemical modification of proteins. As this

• the light, the lamp wattage, and diverse photocatalysts or mechanisms (e.g., energy transfer, photoredox, or electron-donor/electron-acceptor photoinduced electron transfer) might all be brought to bear on controlling the DAR. In addition to the DAR, homogeneity for conjugation at specific sites using

• to study and alter biological systems at the molecular level [52][53]. Owing to the often-unique mechanisms characterized by photocatalytically promoted reactions, reactivity patterns might be developed that allow selective reactions at amino acids that are not currently used for conjugation of

Formaldehyde surrogates in multicomponent reactions

• Cecilia I. Attorresi,
• Javier A. Ramírez and
• Bernhard Westermann

Beilstein J. Org. Chem. 2025, 21, 564–595, doi:10.3762/bjoc.21.45

• medium or lead to the formation of the same final product as that achieved with formaldehyde, but through different reaction mechanisms. Due to the importance of this research, this review aims to summarize and analyze the significant efforts made in this regard in recent years. Major emphasis will be

• in MCR reactions applied to the synthesis of propargylamines and aminophosphonates. We will discuss the reaction conditions, mechanisms, and scope. Synthesis of propargylamines Propargylamines are essential building blocks for the synthesis of natural products or biologically active compounds in

Deep-blue emitting 9,10-bis(perfluorobenzyl)anthracene

• Long K. San,
• Sebastian Balser,
• Brian J. Reeves,
• Tyler T. Clikeman,
• Yu-Sheng Chen,
• Steven H. Strauss and
• Olga V. Boltalina

Beilstein J. Org. Chem. 2025, 21, 515–525, doi:10.3762/bjoc.21.39

• emitters for organic light emitting diodes (OLEDs) [4][5][6][7][8]. More recently, an increased interest in the studies of triplet–triplet annihilation mechanisms in anthracene emitter materials [9] and the design of efficient OLED emitters based on hyperfluorescence [10][11], which could exhibit high

Photomechanochemistry: harnessing mechanical forces to enhance photochemical reactions

• Francesco Mele,
• Ana M. Constantin,
• Andrea Porcheddu,
• Raimondo Maggi,
• Giovanni Maestri,
• Nicola Della Ca’ and
• Luca Capaldo

Beilstein J. Org. Chem. 2025, 21, 458–472, doi:10.3762/bjoc.21.33

• the synthesis of novel compounds and materials. While the mechanisms underlying mechanochemical reactions are still under investigation [47][48][49][50], the increasing body of research demonstrates the potential of this technique to revolutionize synthetic chemistry. Combining photochemistry with

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

• between a simple, highly symmetrical, often hydrophobic pocket of a typical coordination cage host system and the complex, highly unsymmetrical and largely polar environment of an enzyme active site is a moot point… [since]… the mechanisms which an enzyme utilizes to accelerate chemical reactions are in

Unraveling aromaticity: the dual worlds of pyrazole, pyrazoline, and 3D carborane

• Zahra Noori,
• Miquel Solà,
• Clara Viñas,
• Francesc Teixidor and
• Jordi Poater

Beilstein J. Org. Chem. 2025, 21, 412–420, doi:10.3762/bjoc.21.29

• the fact that the fusing C–C bond between o-carborane and the pyrazole is not a double bond? Finally, in agreement with the above discussion on the bond lengths, Pierrefixe and Bickelhaupt revealed the underlying electronic bonding mechanisms in the π-electron and σ-electron systems that cause the

The effect of neighbouring group participation and possible long range remote group participation in O-glycosylation

• Rituparna Das and
• Balaram Mukhopadhyay

Beilstein J. Org. Chem. 2025, 21, 369–406, doi:10.3762/bjoc.21.27

• idea of glycosylation mechanisms to enable the readers to have a background idea as a reference before going to describe the role of protecting groups. The mechanistic pathway of glycosylation strongly depends on many factors, especially, the concentration of the participating moieties, the reaction

• ignored [26][27][28]. However, recent experimental, kinetic, and physical data reveal the incidence of more associative mechanisms [29][30][31] wherein the mechanistic pathway of glycosylation seems to lie at an interface of SN1–SN2 reaction (Scheme 1) [29]. The continuum mechanism expands in two

• pairs in glycosylation mechanisms was first reported by Rhind-Tutt and Vernon [44], and later reiterated by various authors, including the seminal graphical analysis of Lemieux and co-workers [45][46][47]. Thus, complete categorisation of the reaction in either of the subdomains of substitution reaction

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

• plausible mechanisms: a photoinduced electron transfer (PET) between the 3MLCT state of the copper complex and DCA or a triplet–triplet energy transfer (TTET) between the 3MLCT state of the copper complex and DCA. In both of these mechanisms, the involvement of a doublet excited-state of the radical anion

• can engage in electron-transfer mechanisms to enable radical cascade reactions under red-light irradiation (Scheme 9) [37]. These zinc(II)-based porphyrin catalysts operate via an oxidative quenching cycle, directly facilitating the transfer of an electron from the excited state of the porphyrin to

• hydrogen-atom-transfer mechanisms with a Hantzsch ester 34 as presented in Scheme 12. Moreover, the study has explored the impact of substrate steric hindrance and halogen bond strength on catalytic efficiency, revealing that bromo- and iodo-substrates react more efficiently, while chloro-substrates

Dioxazolones as electrophilic amide sources in copper-catalyzed and -mediated transformations

• Seungmin Lee,
• Minsuk Kim,
• Hyewon Han and
• Jongwoo Son

Beilstein J. Org. Chem. 2025, 21, 200–216, doi:10.3762/bjoc.21.12

• recent progress in the chemical transformation of dioxazolones using copper salts. This review provides an overview of the recent achievements in the use of copper salts as sustainable metal systems for the transformation of dioxazolones. This review also discusses several related proposed mechanisms

Recent advances in electrochemical copper catalysis for modern organic synthesis

• Yemin Kim and
• Won Jun Jang

Beilstein J. Org. Chem. 2025, 21, 155–178, doi:10.3762/bjoc.21.9

• , and benzamide, however, no relevant competitive oxidation peak was observed with only Cu(OAc)2. These results indicate that Cu(II) intermediate 5 was generated. Based on the mechanistic studies, the authors suggested plausible reaction mechanisms (Figure 4). First, the Cu(II) catalyst coordinates with

• -catalyzed electrochemical reactions are expected in the near future, developing powerful tools for sustainable and efficient organic syntheses. General mechanisms of traditional and radical-mediated cross-coupling reactions. Types of electrocatalysis (using anodic oxidation). Recent developments and

Nickel-catalyzed cross-coupling of 2-fluorobenzofurans with arylboronic acids via aromatic C–F bond activation

• Takeshi Fujita,
• Haruna Yabuki,
• Ryutaro Morioka,
• Kohei Fuchibe and
• Junji Ichikawa

Beilstein J. Org. Chem. 2025, 21, 146–154, doi:10.3762/bjoc.21.8

• mol %), and cod (10 mol %). bNi(cod)2 (20 mol %), PCy3 (40 mol %), and cod (20 mol %). cK3PO4 (1.2 equiv) was used as a base. dToluene–MeOH–H2O (5:1:1) was used as a solvent. Synthesis of 2-phenylbenzothiophene (5). Orthogonal approach to 2,5-diarylbenzofuran 3fa. Possible mechanisms. Formation of

Cu(OTf)₂-catalyzed multicomponent reactions

• Sara Colombo,
• Camilla Loro,
• Egle M. Beccalli,
• Gianluigi Broggini and
• Marta Papis

Beilstein J. Org. Chem. 2025, 21, 122–145, doi:10.3762/bjoc.21.7

• radical mechanisms. Synthesis of α-aminonitriles 1. Synthesis of β-amino ketone or β-amino ester derivatives 3. Synthesis of 1-(α-aminoalkyl)-2-naphthol derivatives 4. Synthesis of thioaminals 5. Synthesis of aryl- or amine-containing alkanes 6 and 7. Synthesis of 1-aryl-2-sulfonamidopropanes 8. Synthesis

Hot shape transformation: the role of PSar dehydration in stomatocyte morphogenesis

• Remi Peters,
• Levy A. Charleston,
• Karinan van Eck,
• Teun van Berlo and
• Daniela A. Wilson

Beilstein J. Org. Chem. 2025, 21, 47–54, doi:10.3762/bjoc.21.5

• for the use in drug delivery systems [12]. In this regard, synthetic polypeptides emerge as a promising candidate for constructing biodegradable and biocompatible polymersomes. Leveraging the inherent presence of peptide-degrading mechanisms within the human body and the versatile chemical

Facile one-pot reduction of β-nitrostyrenes to phenethylamines using sodium borohydride and copper(II) chloride

• Laura D’Andrea and
• Simon Jademyr

Beilstein J. Org. Chem. 2025, 21, 39–46, doi:10.3762/bjoc.21.4

• Jackson mechanisms (product (a)), which, to date, were only associated to the catalytic hydrogenation of nitrobenzene analogues [35][36][37] (Figure 3). An attempt to identify the higher molecular masses observed by MS was made, and two intermediate structures are proposed in Figure 3. Together with (a

Ceratinadin G, a new psammaplysin derivative possessing a cyano group from a sponge of the genus Pseudoceratina

• Shin-ichiro Kurimoto,
• Kouta Inoue,
• Taito Ohno and
• Takaaki Kubota

Beilstein J. Org. Chem. 2024, 20, 3215–3220, doi:10.3762/bjoc.20.267

• [25][26][27][28]. It is known that natural nitrile compounds are biosynthesized through various mechanisms [29]. Rinehart and co-workers demonstrated that 2-(3,5-dibromo-4-hydroxyphenyl)acetonitrile is biosynthesized from ʟ-tyrosine via 3,5-dibromo-ʟ-tyrosine, based on experiments using 14C- and 15N

Discovery of ianthelliformisamines D–G from the sponge Suberea ianthelliformis and the total synthesis of ianthelliformisamine D

• Sasha Hayes,
• Yaoying Lu,
• Bernd H. A. Rehm and
• Rohan A. Davis

Beilstein J. Org. Chem. 2024, 20, 3205–3214, doi:10.3762/bjoc.20.266

• ; most of which are sessile and lack the ability to physically defend themselves from both predators and competitors and thus rely on chemical mechanisms for their defense [1]. Metabolites derived from marine sponges contribute more than half of all compounds identified from marine invertebrates [1][5

Direct trifluoroethylation of carbonyl sulfoxonium ylides using hypervalent iodine compounds

• Radell Echemendía,
• Carlee A. Montgomery,
• Fabio Cuzzucoli,
• Antonio C. B. Burtoloso and
• Graham K. Murphy

Beilstein J. Org. Chem. 2024, 20, 3182–3190, doi:10.3762/bjoc.20.263

• -mediated and SN2 reaction mechanisms. Ultimately, the nudged elastic band climbing image (NEB-CI) method predicted the SN2 pathway to be favoured, and transition state optimization showed this to possess a Gibbs free energy of activation of 24.3 kcal/mol. This report shows the ease with which sulfoxonium

• mesh) as a stationary phase (eluent n-hex/AcOEt 5:95%). Representative examples of fluorine containing, biologically active compounds. Possible mechanisms for the reaction of 1a and 2a leading to 3a (via B), proceeding via either halogen-bonded adducts and reductive elimination (path 1) or directly via

Hypervalent iodine-mediated intramolecular alkene halocyclisation

• Charu Bansal,
• Oliver Ruggles,
• Albert C. Rowett and
• Alastair J. J. Lennox

Beilstein J. Org. Chem. 2024, 20, 3113–3133, doi:10.3762/bjoc.20.258

• in poor yield with α preference for 7-membered rings 7 in a ratio of 1:9.3. The authors proposed two mechanisms for the reaction (Scheme 1). In pathway A (top), the alkene-activated iodonium is formed, intramolecular attack of nitrogen forms the 6-membered ring A before an SN2 reaction with the

• difluoroiodobenzene 10 is formed in situ, which is activated by HF. Two possible mechanisms were given for the synthesis of pyrrolidines 14, which are the same two proposed for the synthesis of piperidines 6 (Scheme 1). Either an alkene-activated iodonium is formed or an activated electrophilic nitrogen is generated

• tetrahydrofurans 25 and tetrahydropyrans 26. Unsaturated carboxylic acids 24 was also cyclised to form 5-membered fluorinated lactones 27. The mechanisms proposed for the cyclisation of unsaturated alcohols and carboxylic acids both proceed first through the activation of the alkene by the iodane (Scheme 11). The

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

• light turned out to be as effective as blue light, providing good yields of various photochemical reactions that proceed via both oxidative and reductive quenching mechanisms. Further, using of metal-free porphyrins as photocatalysts in bioorthogonal chemistry was explored. They can be utilized in

• evolution reaction (OER). There are several reviews focusing on the relationship between metallo-catalyst structures and HER, OER, and ORR performance/mechanisms, selection of the central metal ion, and peripheral functionalization of the catalysts [106][107][108][109]. This review summarizes recent