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

• the critical role of reaction medium polarity in modulating reactive intermediates, offering a strategic lever to toggle between C–H functionalization and reductive manifolds in photochemical transformations. In 2024, the Cheng group developed a palladium/chiral norbornene (NBE)-catalyzed cyclization

• accumulation of 51. Since 51 is highly stable and resistant to reaction with MeOH (k2R << k2S ≈ k1R), it can be obtained with high optical purity after an extended reaction time (10 hours) In 2023, Yang and Liang jointly reported a tetrasilane (ODCS)-based method for time-controlled, palladium-catalyzed C–H

• the σ-alkylpalladium intermediate Int-50. The intermediate Int-50 undergoes C–H activation to generate the spiro-palladacycle Int-51, which proceeds via two possible pathways: 1) Path a: oxidative addition/reductive elimination or 2) path b: transmetalation/reductive elimination giving rise to

Dicarboxylate recognition based on ultracycle hosts through cooperative hydrogen bonding and anion–π interactions

• Wen-Hui Mi,
• Teng-Yu Huang,
• Xu-Dong Wang,
• Yu-Fei Ao,
• Qi-Qiang Wang and
• De-Xian Wang

Beilstein J. Org. Chem. 2025, 21, 884–889, doi:10.3762/bjoc.21.72

• , while the glycol chains are oriented along the long axis in the opposite orientations. In packing mode, the submacrocycle units form close contacts through intermolecular hydrogen bonding, C–H···π, and lone pair–π interactions, resulting in a 1D linear assembly. Anion recognition With the functional

4-(1-Methylamino)ethylidene-1,5-disubstituted pyrrolidine-2,3-diones: synthesis, anti-inflammatory effect and in silico approaches

• Nguyen Tran Nguyen,
• Vo Viet Dai,
• Luc Van Meervelt,
• Do Thi Thao and
• Nguyen Minh Thong

Beilstein J. Org. Chem. 2025, 21, 817–829, doi:10.3762/bjoc.21.65

• π–π stacking is observed in the crystal packing of the complexes, but only C–H···π interactions are present. Two C–H···O hydrogen bonds complete the interactions stabilizing the crystal packing (Figure S1 and Table S2 in Supporting Information File 1). Inhibitory activity of NO production It is

Recent advances in the electrochemical synthesis of organophosphorus compounds

• Babak Kaboudin,
• Milad Behroozi,
• Sepideh Sadighi and
• Fatemeh Asgharzadeh

Beilstein J. Org. Chem. 2025, 21, 770–797, doi:10.3762/bjoc.21.61

• amides with electron-withdrawing or electron-donating groups on their aromatic ring, producing products with yields ranging from 51% to 82%. In 2023, Lei and co-workers [47] reported an electrochemical C–P bond formation via a coupling reaction of C–H bonds of alkynes, alkenes, and aryl compounds with

• on silver-catalyzed C–H phosphorylation revealed that variations in current intensity, frequency, and duty ratio influence product yield. To achieve optimal reactivity, the duty ratio must exceed 50%. Additionally, an analysis of silver deposition on carbon and platinum electrodes indicated that

• ferrocene and ruthenocene via coupling reaction. This method provides an efficient and versatile synthetic approach for producing phosphorylated metallocenes but also aids in interpreting the regioselectivity and reactivity of C−H functionalization in unsymmetric metallocenes. They used a platinum electrode

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

• fluorine atoms into the structure. The C–F bond has certain fundamental characteristics that enable it to serve as an effective conformational tool (Figure 1) [2][3][4]. First, the C–F bond is quite short at only ≈1.35 Å (cf. ≈1.09 Å for C–H, or ≈1.43 Å for C–O). The short length of the C–F bond, and the

• polar C–F bonds at the end of an alkyl chain, is that the terminal C–H bond also becomes polarised. In the case of the difluoromethyl group, the terminal hydrogen bears a partial positive charge and is able to act as a H-bond donor (II, Figure 2). This can influence the conformation of the molecule if

• rotamers have different energies. When the C–F bonds are aligned gauche, the vacant σ* orbital of each C–F bond is able to mix with the filled σ orbital of an adjacent C–H bond, and this hyperconjugative interaction stabilises the gauche conformer (III, Figure 2). The anti conformer does not benefit from

Entry to 2-aminoprolines via electrochemical decarboxylative amidation of N‑acetylamino malonic acid monoesters

• Olesja Koleda,
• Janis Sadauskis,
• Darja Antonenko,
• Edvards Janis Treijs,
• Raivis Davis Steberis and
• Edgars Suna

Beilstein J. Org. Chem. 2025, 21, 630–638, doi:10.3762/bjoc.21.50

• observed by LC–MS when the electrolysis was performed in 5:1 MeCN/D2O (Scheme 2, reaction 2). The considerably higher O–H bond dissociation energy (119 kcal/mol) [12] as compared to that of the C–H bond in MeCN (86 kcal/mol) [13] renders the hydrogen atom abstraction from water by a carbon-centered radical

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

• (DMF), dimethyl sulfoxide (DMSO), or dioxane to achieve high yields. The assumed mechanism is initiated by activation of the C–H bond of the terminal alkyne by a metal catalyst. The resulting metal acetylide reacts with the imine/enamine through a nucleophilic addition. Because imines/enamines are

• . These are the basis for the AHA coupling: amine–haloalkane–alkyne coupling for the synthesis of propargylamines by the activation of both C–H and C–X bonds by metal catalysis (Scheme 20). In general, the activation of both CH and CX bonds is accomplished by homogeneous metal catalysis with CuCl being

• to the AAA coupling, except for iron, where the temperature must be increased to 100 °C. This can be explained in terms of the activation of both the C–H and C–X bonds by metal catalysis, which is not the case in AAA couplings, where only the C–H bond is activated, making the last step (nucleophilic

Unprecedented visible light-initiated topochemical [2 + 2] cycloaddition in a functionalized bimane dye

• Metodej Dvoracek,
• Brendan Twamley,
• Mathias O. Senge and
• Mikhail A. Filatov

Beilstein J. Org. Chem. 2025, 21, 500–509, doi:10.3762/bjoc.21.37

• groups play a role by increasing the number of hydrogen bonds (C–H···O, 3.18(5)–3.62(6) Å) The intermolecular distances between the C–H groups and the chlorine atoms in Cl2B (A) are C13A–H13···Cl1A, 3.69(5), and C18A–H18C···Cl2A, 3.69(3) Å, indicating further molecular attraction [22]. A previously

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

• light and promote mass transfer. As understanding of the methodology advances, the development of more complex synthetic strategies, including C–H, C–C, and C–heteroatom-bond formation, is expected [79]. Moreover, we anticipate that the difference in photophysical properties between organic molecules in

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

• ]. Lattices can also contain defects, which may affect catalytic activity unpredictably [228]. Nonetheless, macroscale structures, like those that arise from the stacking in 2D COFs, can contribute to catalysis, for instance dense arrays of aligned C–H bonds can provide CH–π interactions in Diels–Alder

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

• enantioselectivity. Furthermore, a lactam containing a quaternary carbon center (2g) was prepared. However, a lower enantioselectivity was observed for product 2h due to the similar steric environment of the two alkyl substituents. As shown in Figure 1, a catalytic cycle was proposed for the intramolecular C–H

Quantifying the ability of the CF₂H group as a hydrogen bond donor

• Matthew E. Paolella,
• Daniel S. Honeycutt,
• Bradley M. Lipka,
• Jacob M. Goldberg and
• Fang Wang

Beilstein J. Org. Chem. 2025, 21, 189–199, doi:10.3762/bjoc.21.11

• reveal the fundamental differences between the C–H bond and the O–H bond as HB donors and provide important quantitative information for applying the CF2H group as an OH group mimic. We next attempted to establish correlations of experimentally determined HB donation ability, in terms of Kd or ΔGexp

Hydrogen-bonded macrocycle-mediated dimerization for orthogonal supramolecular polymerization

• Wentao Yu,
• Zhiyao Yang,
• Chengkan Yu,
• Xiaowei Li and
• Lihua Yuan

Beilstein J. Org. Chem. 2025, 21, 179–188, doi:10.3762/bjoc.21.10

• noncovalent interactions, particularly intermolecular π–π-stacking and C–H···O interactions. Specifically, π–π-stacking interactions were found between two guest molecules with aromatic rings arrayed in an offset fashion with a distance of 3.3 Å (Figure 3a). Interestingly, these interactions also existed

• /or π-stacking interactions, conferring the characteristic 2:2 constitutional stoichiometry onto this host–guest complex. In addition, there were eight C–H···O interactions between the hydrogen atoms of G1 and the nearby pyridinium group of H2, with distances of 2.2–3.5 Å, and two C–H···O interactions

• and G1. The brown dotted lines show the hydrogen bond distance between H2 and the positively charged region of G1 (d[C–H···O] = 2.2–3.5 Å). The red dotted lines show the hydrogen bond distance between H2 and the proton of the phenyl group of G1 (d[C–H···O] = 2.7–2.9 Å). c) Dimeric structure showing

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

• ][22][23][24]. Moreover, copper-catalyzed asymmetric radical cross-coupling has advanced significantly over the past decade [25][26][27], with notable examples including Liu and Stahl’s enantioselective cyanation of benzylic C–H bonds using a Cu/chiral bisoxazoline catalyst [28], along with the Peters

• catalysis to organic synthesis, focusing on recent developments in Cu-catalyzed electrochemical reaction categorized into four types: 1) C–H functionalization, 2) olefin addition, 3) decarboxylative functionalization, and 4) coupling reactions (Figure 3). This review aims to provide insight into the

• potential of copper-based electrochemical methodologies while also inspiring future research in this rapidly growing field. Review C–H Functionalization Site- and chemoselective C–H functionalization has emerged as a powerful platform for the formation of new C–C and C–heteroatom bonds, offering an

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

• multicomponent synthesis of acyclic and heteropolycyclic systems under copper(II) triflate catalysis are reported. Using alkenes and alkynes as substrates, various types of reactions were considered, including hydroamination, condensation, cross-coupling, C–H functionalization, cycloaddition, aza-Diels–Alder

Recent advances in organocatalytic atroposelective reactions

• Henrich Szabados and
• Radovan Šebesta

Beilstein J. Org. Chem. 2025, 21, 55–121, doi:10.3762/bjoc.21.6

• amines 76 in the C–H amination reaction with CPA C25, the authors were able to prepare axially chiral para-amination products 78 (Scheme 25) [49]. Such amination products 78 were prepared with high levels of yields and showed remarkable enantiomeric purities. Interestingly, when a phenyl substituent was

• , not the organocatalyst nor the product being formed, effectively absorb the light. An atroposelective C–H amination was done with the help of SPINOL-derived chiral phosphoric acids C51, C40, and C42 (Scheme 66) [96]. It was a reaction of naphthalenyldiazene carboxylates 222 with derivatives of

Emerging trends in the optimization of organic synthesis through high-throughput tools and machine learning

• Pablo Quijano Velasco,
• Kedar Hippalgaonkar and
• Balamurugan Ramalingam

Beilstein J. Org. Chem. 2025, 21, 10–38, doi:10.3762/bjoc.21.3

Synthesis of acenaphthylene-fused heteroarenes and polyoxygenated benzo[j]fluoranthenes via a Pd-catalyzed Suzuki–Miyaura/C–H arylation cascade

• Merve Yence,
• Dilgam Ahmadli,
• Damla Surmeli,
• Umut Mert Karacaoğlu,
• Sujit Pal and
• Yunus Emre Türkmen

Beilstein J. Org. Chem. 2024, 20, 3290–3298, doi:10.3762/bjoc.20.273

• %). This cascade involves an initial Suzuki–Miyaura cross-coupling reaction between 1,8-dihalonaphthalenes and heteroarylboronic acids or esters, followed by an intramolecular C–H arylation under the same conditions to yield the final heterocyclic fluoranthene analogues. The method was further employed to

• total synthesis of the fungal natural product bulgarein. Keywords: acenaphthylene-fused heteroarenes; benzo[j]fluoranthenes; C–H arylation; fluoranthenes; heterocycles; Introduction An important subclass of polycyclic aromatic hydrocarbons (PAHs) [1] is comprised of fluoranthenes, which have been the

• -based natural product, which was discovered to induce topoisomerase I-mediated DNA cleavage [16][17]. For the construction of the fluoranthene skeleton, a broad range of synthetic strategies including C–H arylation [18][19][20][21][22], Diels–Alder [7][8][23][24][25] and [2 + 2 + 2] cycloadditions [26

Intramolecular C–H arylation of pyridine derivatives with a palladium catalyst for the synthesis of multiply fused heteroaromatic compounds

• Yuki Nakanishi,
• Shoichi Sugita,
• Kentaro Okano and
• Atsunori Mori

Beilstein J. Org. Chem. 2024, 20, 3256–3262, doi:10.3762/bjoc.20.269

• Abstract The C–H arylation of 2-quinolinecarboxyamide bearing a C–Br bond at the N-aryl moiety is carried out with a palladium catalyst. The reaction proceeds at the C–H bond on the pyridine ring adjacent to the amide group in the presence of 10 mol % Pd(OAc)2 at 110 °C to afford the cyclized product in 42

• % yield, respectively. The related reaction is also carried out with amides of non-pyridine derivatives terephthal- and benzamides to afford multiply fused heterocyclic compounds in 81% and 89% yields, respectively. Keywords: intramolecular C–H arylation; multiply fused heterocycles; palladium acetate

• ; phosphine ligand; pyridine amides; Introduction Transition-metal-catalyzed synthetic reactions have recently attracted much attention in synthetic organic chemistry [1][2]. C–H Arylation reactions catalyzed by a transition metal are of particular interest because these reactions involve rather superior

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

• ]. This synthetic potential has been demonstrated in a range of insertions into polar bonds [17][18][19][20], C−H activation transformations [21][22][23], and geminal difunctionalizations [24][25]. Within the literature, a broad array of classical methods describes the synthesis of sulfoxonium ylides [26

Multicomponent reactions driving the discovery and optimization of agents targeting central nervous system pathologies

• Lucía Campos-Prieto,
• Aitor García-Rey,
• Eddy Sotelo and
• Ana Mallo-Abreu

Beilstein J. Org. Chem. 2024, 20, 3151–3173, doi:10.3762/bjoc.20.261

• a multicomponent reaction to obtain SIRT2 inhibitors (Scheme 12). The authors suggest a Knoevenagel condensation approach between isatin derivatives and ethyl cyanoacetate, followed by a Michael addition with C–H activated carbonyl compounds and intramolecular cyclization [50]. They synthesized 45

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

• metal-free macrocycles for the C–H arylation of five-membered heteroarenes using aryldiazonium salts, with porphyrin serving as the photoredox catalyst [92]. Control experiments indicated that H2TPP (18), when irradiated with light, gave 80% yield of the C–H arylated product 77 for the reaction of furan

• red light irradiation [97]. Firstly, they evaluated the photoreductant role of metal-free macrocycles, H2TPP (18) and PPIX 78, in the red light-induced C–H arylation of different substrates such as furan, coumarin, thiol, pivalamide, aryl thiaether and the selenium equivalents. Use of both macrocycles

• combining the organocatalytic and photocatalytic potential of porphyrin macrocycles [98]. In 2024, Gupta and colleagues expanded on the success of free base porphyrin macrocycles as photoredox catalysts by introducing meso-arylcorroles (types A3 and A2B) for C–H arylation and borylation reactions activated

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

• . Keywords: C–H functionalization; oxidation; peroxidation; radical reactions; TBHP; Introduction Organic peroxides are used in many different areas of human activities. The traditional and most developed field is the use of peroxides as initiators in the polymerization process for the production of a wide

• broad, the present review mainly focused on radical and metal-catalyzed functionalization of C–H bonds or unsaturated bond with hydroperoxides (Scheme 2). The aim of this review is to cover recent studies in which alkylperoxy radicals have been used for the peroxidation of C(sp3) and C(sp2) sites

• ROOH, but most of them were published after 2010. Review C(sp3)–H peroxidation Allylic C(sp3)–H The pioneering work on C–H radical peroxidation with hydroperoxides was published by Kharasch in a series of articles entitled "The Chemistry of Hydroperoxides" in the 1950s [24][37][38]. Kharasch with

Recent advances in transition-metal-free arylation reactions involving hypervalent iodine salts

• Ritu Mamgain,
• Kokila Sakthivel and
• Fateh V. Singh

Beilstein J. Org. Chem. 2024, 20, 2891–2920, doi:10.3762/bjoc.20.243

• easily recycled just by washing it with ethanol, retaining its catalytic activity for arylation up to three cycles without any compromise. Thus, this procedure could be considered economic as well as environment-friendly. In 2019, Kalek and co-workers reported the regioselective C–H arylation of 2

• –acceptor (EDA) complex. The complex is formed of triphenylphosphine, sodium iodide and N,N,N,N-tetramethylethylenediamine (TMEDA) with diaryliodonium reagents (DAIRs) [64]. This activates DAIRs 16 to generate an aryl radical which is utilized in the C–H arylation of various heterocycles 31 to yield the

C–H Trifluoromethylthiolation of aldehyde hydrazones

• Victor Levet,
• Balu Ramesh,
• Congyang Wang and
• Tatiana Besset

Beilstein J. Org. Chem. 2024, 20, 2883–2890, doi:10.3762/bjoc.20.242

• /Education Center for Excellence in Molecular Sciences Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China 10.3762/bjoc.20.242 Abstract The selective C–H trifluoromethylthiolation of aldehyde hydrazones afforded interesting fluorinated building blocks, which could be used as a

• ). Mechanistic investigations revealed that AgSCF3 was the active species in the transformation. Keywords: C–H bond functionalization; C–S bond formation; hydrazones; synthetic method; trifluoromethylthiolation; Introduction Fluorinated molecules are of paramount importance [1][2][3][4][5][6][7][8][9][10][11

• various transformations [54][55][56][57][58][59][60][61][62][63][64]. In consequence, a large number of transition-metal-catalyzed or radical-mediated processes for C–H functionalization of aldehyde hydrazones has flourished over the years. An ideal scenario for a direct and sustainable synthetic route