Recent advances in Norrish–Yang cyclization and dicarbonyl photoredox reactions for natural product synthesis

• Peng-Xi Luo,
• Jin-Xuan Yang,
• Shao-Min Fu and
• Bo Liu

Beilstein J. Org. Chem. 2025, 21, 2315–2333, doi:10.3762/bjoc.21.177

• safety and controllability of the reaction, and at the same time, it is also conducive to the rapid optimization of reaction conditions and scale-up production. Finally, the Norrish–Yang reaction can utilize artificial intelligence to assist in designing reaction routes in the future, and through big

Enantioselective radical chemistry: a bright future ahead

• Anna C. Renner,
• Sagar S. Thorat,
• Hariharaputhiran Subramanian and
• Mukund P. Sibi

Beilstein J. Org. Chem. 2025, 21, 2283–2296, doi:10.3762/bjoc.21.174

• individually or synergistically with other catalytic systems. Enzymatic catalysis can pose challenges including enzyme engineering, reaction scale-up, etc. but is optimal in terms of the toxicity profile of the reaction conditions. Biomolecules such as enzymes are attractive candidates for efficient and

• for applications in radical chemistry. Compared with conventional batch synthesis, flow chemistry can improve efficiency and facilitate reaction scale-up [87][88][89][90]. Mechanochemistry allows reactions to be conducted with no solvent or with only a small volume of added liquid, thus providing a

Pd-catalyzed dehydrogenative arylation of arylhydrazines to access non-symmetric azobenzenes, including tetra-ortho derivatives

• Loris Geminiani,
• Kathrin Junge,
• Matthias Beller and
• Jean-François Soulé

Beilstein J. Org. Chem. 2025, 21, 2234–2242, doi:10.3762/bjoc.21.170

• avoiding excess reagent, and simplifies purification and scale-up. With the most suitable reaction conditions in hand, the substrate scope was examined. First, the reactivity of different aryl bromides with phenylhydrazine (1a) to form non-symmetric azobenzene was explored (Scheme 1). Most of the

Stereoselective electrochemical intramolecular imino-pinacol reaction: a straightforward entry to enantiopure piperazines

• Margherita Gazzotti,
• Fabrizio Medici,
• Valerio Chiroli,
• Laura Raimondi,
• Sergio Rossi and
• Maurizio Benaglia

Beilstein J. Org. Chem. 2025, 21, 1897–1908, doi:10.3762/bjoc.21.147

• and in view of a possible scale up of the reaction [51][52]. Flow experiments were performed using the commercially available pre-configured Syrris-Asia electrochemical flow module, a user-friendly solution for continuous flow electrochemical synthesis which is part of the Asia platform [53]. A

Fe-catalyzed efficient synthesis of 2,4- and 4-substituted quinolines via C(sp²)–C(sp²) bond scission of styrenes

• Prafull A. Jagtap,
• Manish M. Petkar,
• Vaishnavi R. Sawant and
• Bhalchandra M. Bhanage

Beilstein J. Org. Chem. 2025, 21, 1799–1807, doi:10.3762/bjoc.21.142

• broad range of styrenes and arylamines, into valuable quinolines with good to excellent yields under environmentally benign and mild reaction conditions. The successful execution of a scale-up reaction to synthesize single-step antifungal agents emphasizes the significant synthetic potential of this

• approach in chemical synthesis and drug discovery. Representative examples of bioactive quinolines. C(sp2)–C(sp2) bond-cleavage strategies for quinoline synthesis. Substrate scope of various arylamines and styrenes. Scale-up studies for the synthesis of antifungal agents. Mechanistic investigations

Preparation of a furfural-derived enantioenriched vinyloxazoline building block and exploring its reactivity

• Madara Darzina,
• Anna Lielpetere and
• Aigars Jirgensons

Beilstein J. Org. Chem. 2025, 21, 1737–1741, doi:10.3762/bjoc.21.136

• . Further scale-up could be achieved by switching to flow conditions, or designing a continuous tank reactor [27]. Several attempts were made to explore enantioenriched vinyloxazoline 6 as a chiral building block. While additions to the double bond were not successful, vinyloxazoline 6 was found to be a

Continuous-flow-enabled intensification in nitration processes: a review of technological developments and practical applications over the past decade

• Feng Zhou,
• Chuansong Duanmu,
• Yanxing Li,
• Jin Li,
• Haiqing Xu,
• Pan Wang and
• Kai Zhu

Beilstein J. Org. Chem. 2025, 21, 1678–1699, doi:10.3762/bjoc.21.132

• system configuration strategies, critical process parameters and operating ranges, performance evaluation metrics, universal methodologies for kinetics analysis, safety assessment protocols, and scale-up approaches. The presented content aims to offer actionable guidance for researchers and engineers

• engaged in the development of continuous-flow nitration systems. Keywords: continuous-flow; kinetics; nitration; optimization; scale up; Introduction Nitro compounds hold an extremely important position in the field of organic chemistry, mainly because they are easily obtainable and can be converted

• coexist with engineering bottlenecks requiring optimization in process safety and scale-up strategies. Contemporary research endeavors prioritize two synergistic pathways: (i) pioneering alternative nitration pathways via innovative chemical approaches, particularly through novel nitrating agent

General method for the synthesis of enaminones via photocatalysis

• Paula Pérez-Ramos,
• Raquel G. Soengas and
• Humberto Rodríguez-Solla

Beilstein J. Org. Chem. 2025, 21, 1535–1543, doi:10.3762/bjoc.21.116

• photocatalyst. Examples of compounds with medicinal effects containing an enaminone structural moiety. Synthesis of enaminones. Substrate scope. Scale-up synthesis of enaminone 9a. Mechanistic studies. Proposed mechanism. Optimization of reaction conditions. Supporting Information Supporting Information File 6

High-pressure activation for the solvent- and catalyst-free syntheses of heterocycles, pharmaceuticals and esters

• Kelsey Plasse,
• Valerie Wright,
• Guoshu Xie,
• R. Bernadett Vlocskó,
• Alexander Lazarev and
• Béla Török

Beilstein J. Org. Chem. 2025, 21, 1374–1387, doi:10.3762/bjoc.21.102

• of important heterocycles, the synthesis of well-known APIs, such as acetaminophen and acetylsalicylic acid, a variety of esterification reactions and the successful scale up (up to 100 g scale) of the Paal–Knorr reaction. The use of HHP appears to provide several advantages, for example, resulting

• pressurization even at 80 °C. However, the reaction rate with AcOH is still much improved under high pressure, as none of the alcohols formed any product under 1 bar pressure. Scale up of the HHP-assisted reactions The above protocols were carried out at a small scale (mg to g) and thus, an effort was made to

• investigate the scale-up potential of the HHP-assisted method. Although the HHP-assisted organic syntheses are relatively rare, the large (often ton) scale-capable equipment is readily available in the food industry. Accordingly, industrial level organic syntheses are attainable in a large scale. In an

Gold extraction at the molecular level using α- and β-cyclodextrins

• Susana Santos Braga

Beilstein J. Org. Chem. 2025, 21, 1116–1125, doi:10.3762/bjoc.21.89

• the constant composition of 2:1 for α-CD to KAuBr4, in consistency with the single-crystal X-ray data. Application studies in gold mining facilities Process patenting and scale-up pilot trials in the United States: The discovery that α-CD can quickly precipitate gold, as detailed in the previous

• γ-CDs, other acids (including hydrogen halides, nitric acid, sulfuric acid, and mixtures thereof) and sodium hydroxide (instead of potassium hydroxide) [43]. Scale-up pilot trials on 20 batch samples were conducted in Arizona with partnership from companies already active in the market. Results

• of precipitating gold from a solution even when it is found in low concentrations and the possibility of operating at ambient temperature. Lab-scale tests with e-waste recovery show promising extraction yields. Future developments will further optimize parameters and scale up the procedure

Pd-Catalyzed asymmetric allylic amination with isatin using a P,olefin-type chiral ligand with C–N bond axial chirality

• Natsume Akimoto,
• Kaho Takaya,
• Yoshio Kasashima,
• Kohei Watanabe,
• Yasushi Yoshida and
• Takashi Mino

Beilstein J. Org. Chem. 2025, 21, 1018–1023, doi:10.3762/bjoc.21.83

• asymmetric allylic amination of allylic esters with isatin derivatives 11 as nucleophiles. The reaction proceeds efficiently, yielding the products (S)-13 with good-to-high enantioselectivity. A scale-up reaction was also successfully conducted at a 1 mmol scale. Additionally, when malononitrile was added to

• product (S)-13a was obtained with a yield of 50% and an enantioselectivity of 86% ee (Table 1, entry 13). Additionally, the scale-up reaction using 1 mmol of isatin (11a) as the nucleophile under the optimal conditions (Table 1, entry 12) afforded the desired product (S)-13a with nearly the same yield and

Harnessing tethered nitreniums for diastereoselective amino-sulfonoxylation of alkenes

• Shyam Sathyamoorthi,
• Appasaheb K. Nirpal,
• Dnyaneshwar A. Gorve and
• Steven P. Kelley

Beilstein J. Org. Chem. 2025, 21, 947–954, doi:10.3762/bjoc.21.78

• examples of amino-sulfonoxylations using tethered nitreniums. Putative reaction mechanism. (A) Scale-up and (B) applications. Optimization results. Structure–reactivity relationship with nitrenium tethers. Examination of sulfonic acid scope. Substrate scope exploration with an emphasis on stereocontrol and

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

• experiments, a radical process was proposed for this coupling reaction via an Mn(III)–P intermediate (Scheme 9). The method was also applied to scale up to gram-scale synthesis. In 2023, Wu et al. [54] also reported another heteroaromatic C–P coupling of benzothiazole with diarylphosphine oxides by an

Copper-catalyzed domino cyclization of anilines and cyclobutanone oxime: a scalable and versatile route to spirotetrahydroquinoline derivatives

• Qingqing Jiang,
• Xinyi Lei,
• Pan Gao and
• Yu Yuan

Beilstein J. Org. Chem. 2025, 21, 749–754, doi:10.3762/bjoc.21.58

• spirotetrahydroquinoline (STHQ) scaffolds. Substrate scope. General reaction conditions: aniline 1 (0.2 mmol), 2 (0.4 mmol), and Cu(TFA)2 (0.04 mmol) in hexane (2.0 mmol) under air atmosphere, 12 h, 80 °C. Yields refer to isolated yields. Scale-up reaction.a Proposed mechanism. Optimization of reaction conditions.a

Synthesis and characterizations of highly luminescent 5-isopropoxybenzo[rst]pentaphene

• Islam S. Marae,
• Jingyun Tan,
• Rengo Yoshioka,
• Zakaria Ziadi,
• Eugene Khaskin,
• Serhii Vasylevskyi,
• Ryota Kabe,
• Xiushang Xu and
• Akimitsu Narita

Beilstein J. Org. Chem. 2025, 21, 270–276, doi:10.3762/bjoc.21.19

• literature. During our attempt to scale up the preparation of BPP 2 through the "DPEX" reaction, we unexpectedly obtained a 5-isopropoxy-substituted derivative of BPP (BPP-OiPr 3) (Scheme 1), whose structure was proven by NMR, mass spectrometry, and X-ray crystallography. In this work, we optimized the

Synthesis of disulfides and 3-sulfenylchromones from sodium sulfinates catalyzed by TBAI

• Zhenlei Zhang,
• Ying Wang,
• Xingxing Pan,
• Manqi Zhang,
• Wei Zhao,
• Meng Li and
• Hao Zhang

Beilstein J. Org. Chem. 2025, 21, 253–261, doi:10.3762/bjoc.21.17

• ) gave more than moderate yields of the corresponding products. To evaluate the feasibility of the process in scale-up studies, gram-scale 2a was synthesized under optimized conditions. The reactions of 1a (1.760 g, 10 mmol) with H2SO4 (10 mmol) and TBAI (2 mmol) gave the corresponding 1,2-di-p

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

• group developed the electrocatalytic racemic C(sp³)–H alkynylation of THIQs with terminal alkynes in a continuous-flow microreactor using copper/TEMPO relay catalysis [51]. The electrocatalytic reaction in continuous flow facilitates straightforward scale-up and demonstrating a broad substrate scope. In

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

• 50 °C in isopropanol just after a couple of hours. The racemization barriers of the products were only slightly higher (28 kcal/mol) than the minimal requirement for separation of atropoisomers (24 kcal/mol). Scale-up done on the one-mmol-scale provided the corresponding product in comparable yields

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

• . [6], and Sagmeister et al. [7]. The first two offer valuable perspectives on chemical reaction optimization, particularly focusing on process scale-up, while the latter discusses the potential of flow platforms for self-optimization reactions. Additionally, we refer the readers to the following

• model for scale-up within approximately eight hours. Their platform consisted of a flow reactor connected to an in-line FTIR spectrometer. In addition, the platform has two valves that allow a stream of reagents or target product to bypass the reactor coil directly into the in-line FTIR spectrometer

Non-covalent organocatalyzed enantioselective cyclization reactions of α,β-unsaturated imines

• Sergio Torres-Oya and
• Mercedes Zurro

Beilstein J. Org. Chem. 2024, 20, 3221–3255, doi:10.3762/bjoc.20.268

• reaction of isocyanoacetates and saccharin-derived 1-azadienes. Enantioselective squaramide-catalyzed asymmetric IEDADA reaction of benzofuran-derived azadienes and silyl (di)enol ethers. Scale up and derivatizations of benzofuran-fused 2-piperidinol derivatives. Dihydroquinine-derived squaramide-catalyzed

Cyclodextrin-based rotaxanes for polymer materials: challenge on simultaneous realization of inexpensive production and defined structures

• Yosuke Akae

Beilstein J. Org. Chem. 2024, 20, 3026–3049, doi:10.3762/bjoc.20.252

• material. Concurrently, implementing a scale-up synthesis procedure to exploit the application potential of rotaxane-based polymers induces structural ambiguities, thereby presenting a significant trade-off between realizing inexpensive production and defined structures. To overcome this rotaxane-synthesis

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

• (Scheme 4A). Pleasingly, the scale up of the reaction was smoothly conducted. Under standard reaction conditions, product 2a (1.2 g) was afforded starting from 1a (1 g), showcasing the robustness of the transformation (Scheme 4B). Intrigued about the nature of the active source of SCF3 in the

Transition-metal-free decarbonylation–oxidation of 3-arylbenzofuran-2(3H)-ones: access to 2-hydroxybenzophenones

• Bhaskar B. Dhotare,
• Seema V. Kanojia,
• Chahna K. Sakhiya,
• Amey Wadawale and
• Dibakar Goswami

Beilstein J. Org. Chem. 2024, 20, 2655–2667, doi:10.3762/bjoc.20.223

• to scale-up due to their violent reactions at elevated temperatures. Our protocol involved mild conditions, and to our expectations, a gram-scale conversion of 3ba to 4ba proceeded smoothly without appreciable loss in the reaction yield (Scheme 3). The reduced reaction time and a lower reaction

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

Catalysing (organo-)catalysis: Trends in the application of machine learning to enantioselective organocatalysis

• Stefan P. Schmid,
• Leon Schlosser,
• Frank Glorius and
• Kjell Jorner

Beilstein J. Org. Chem. 2024, 20, 2280–2304, doi:10.3762/bjoc.20.196