Pathway economy in cyclization of 1,n-enynes

• Hezhen Han,
• Wenjie Mao,
• Bin Lin,
• Maosheng Cheng,
• Lu Yang and
• Yongxiang Liu

Beilstein J. Org. Chem. 2025, 21, 2260–2282, doi:10.3762/bjoc.21.173

• control principles for gold catalysis. Temperature-controlled cyclization of 1,n-enynes Temperature, a pivotal thermodynamic parameter, not only governs reaction kinetics but also determines reaction pathways. Typically, kinetic product formation is favored at lower temperatures via pathways with reduced

C2 to C6 biobased carbonyl platforms for fine chemistry

• Jingjing Jiang,
• Muhammad Noman Haider Tariq,
• Florence Popowycz,
• Yanlong Gu and
• Yves Queneau

Beilstein J. Org. Chem. 2025, 21, 2103–2172, doi:10.3762/bjoc.21.165

• synthesized by the sol–gel method. The 5Mg/SiO2 catalyst showed the highest activity in terms of selectivity and yield because of its suitable basic and acidic density. The addition of Mn to the 5Mg/SiO2 (1Mn-5Mg/SiO2) catalyst as week acidic side increased the selectivity towards 3-HPA. According to reaction

• kinetics studies, the cross-aldol reaction of formaldehyde and acetaldehyde gives a higher yield of 3-HPO than the self-aldol reaction of acetaldehyde. Moreover, Raney nickel was applied successfully for the conversion of 3-HPO to 1,3-PDO with good yield and about 90% conversion rate of 3-HPO (Scheme 13

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

• continuous-flow nitration technology – a process historically recognized as one of the most hazardous industrial operations – focusing on its technological advancements in process design, reaction kinetics characterization, and practical implementation over the past decade. Detailed discussions encompass

• compliance or specific product distribution patterns. Nitration solvents: The selection of solvents for nitration reactions significantly influences reaction kinetics, selectivity, and process safety, requiring careful consideration of both chemical compatibility and operational parameters. Traditional batch

• involving solids and precipitations, CSTRs provide robust solids-handling solutions through controlled suspension mechanisms. The selection of reactor configurations for continuous-flow nitration systems is dictated by an interplay of technical and engineering criteria, encompassing reaction kinetics

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

• that could lead to molecular re-alignments during compression and decompression steps that are beneficial for reaction kinetics. Under optimized conditions, the products were isolated with good to excellent yields under a catalyst- and solvent-free environment (Scheme 3). The data in Scheme 3

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

• control regioselectivity. It profoundly influences reaction kinetics, stability of intermediates, and reaction equilibria. Through precise temperature modulation, chemists can effectively steer the formation of regioisomers, often achieving desired selectivity with minimal alterations to other 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

• oxidize boronic acids such as 47, producing the corresponding alcohols 48 via a single-electron-transfer mechanism that leverages atmospheric oxygen (Scheme 13). While the initial photocatalytic results using NIR-irradiated 46 were promising, the overall reaction kinetics were relatively slow. In response

• heptamethin chain have been proven to be the most effective photocatalysts for accelerating the aza-Henry reaction. The differing reaction kinetics and tests with 9,10-dimethylanthracene suggest that a cooperative mechanism involving both single-electron transfer and singlet oxygen generation via energy

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

• consisting of multiple independent parallel reactors. This parallelization enables the collection of high-fidelity data for reaction kinetics and optimization for at least six different chemical reactions. The major bottleneck in HTE synthesis lies in the challenge of isolating and purifying 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

• efficient method for C–H functionalization. The continuous flow setup allows for precise control over reaction conditions, enhanced mass transfer, and improved reaction kinetics, leading to higher efficiency and faster reaction times. In 2023, the Chiang group reported the photoelectrochemical homo-coupling

Homogeneous continuous flow nitration of O-methylisouronium sulfate and its optimization by kinetic modeling

• Jiapeng Guo,
• Weike Su and
• An Su

Beilstein J. Org. Chem. 2024, 20, 2408–2420, doi:10.3762/bjoc.20.205

• -order (Equation 3) reaction kinetics, where xIO represented the conversion of IO and t denoted the reaction time. The outcome of these fittings is presented in Figure 3a for first-order and Figure 3b for second-order. Notably, the higher R2 observed in Figure 3a compared to Figure 3b suggests that the

• . Determining the apparent reaction kinetics The variation in the conversion of IO (xIO) as the function of time (t) at different temperatures (30 °C, 35 °C, 40 °C) and H2SO4 mass fractions (88%, 90%, 92%, 94%, 96%, and 98%) is depicted in Figure S3 in Supporting Information File 1 and subsequently modeled

• concentrations. Determining the intrinsic reaction kinetics Given the strong correlation between the observed HNO3-based reaction rate constant and the H2SO4 mass fraction, intrinsic reaction constants independent of H2SO4 concentrations were determined to study the intrinsic kinetics of the reaction. Previous

Evaluating the halogen bonding strength of a iodoloisoxazolium(III) salt

• Dominik L. Reinhard,
• Anna Schmidt,
• Marc Sons,
• Julian Wolf,
• Elric Engelage and
• Stefan M. Huber

Beilstein J. Org. Chem. 2024, 20, 2401–2407, doi:10.3762/bjoc.20.204

• significantly slower activation, which results in an amide consumption of only ca. 30% after 4 hours. To quantify the activity differences of these XB donors, the reaction kinetics were fitted according to a pseudo-first-order rate. Only selected periods (the first four data points within the first 1.5 hours of

Improved deconvolution of natural products’ protein targets using diagnostic ions from chemical proteomics linkers

• Andreas Wiest and
• Pavel Kielkowski

Beilstein J. Org. Chem. 2024, 20, 2323–2341, doi:10.3762/bjoc.20.199

• CuAAC due to its rapid reaction kinetics, robustness, and relatively small steric hindrance of the terminal alkyne, which is usually attached to the probe core scaffold to form an alkyne probe [5][63]. Once the covalent bond between the probe and protein is formed, the cells are lysed, and the probe

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

Metal-free double azide addition to strained alkynes of an octadehydrodibenzo[12]annulene derivative with electron-withdrawing substituents

• Naoki Takeda,
• Shuichi Akasaka,
• Susumu Kawauchi and
• Tsuyoshi Michinobu

Beilstein J. Org. Chem. 2024, 20, 2234–2241, doi:10.3762/bjoc.20.191

• indicates that the formed double azide adduct is 6a, which is consistent with our previous report [18]. The double azide addition was further investigated by changing the reaction temperature. The rate constant was determined by the temperature-dependent 1H NMR spectra in CDCl3. The reaction kinetics

Factors influencing the performance of organocatalysts immobilised on solid supports: A review

• Zsuzsanna Fehér,
• Dóra Richter,
• Gyula Dargó and
• József Kupai

Beilstein J. Org. Chem. 2024, 20, 2129–2142, doi:10.3762/bjoc.20.183

• and changes in the reaction kinetics. The non-covalent immobilisation of chiral organocatalysts can also be carried out within deep eutectic solvents (DESs). Very recently, a cinchonidine-squaramide organocatalyst was immobilised in three types of natural DESs, namely betaine/sorbitol/water, betaine

Benzylic C(sp³)–H fluorination

• Alexander P. Atkins,
• Alice C. Dean and
• Alastair J. J. Lennox

Beilstein J. Org. Chem. 2024, 20, 1527–1547, doi:10.3762/bjoc.20.137

• and oxidation potentials. Electrochemical methods Synthetic electrochemistry is a powerful tool offering excellent control over reaction kinetics and selectivity [86]. Electrochemical oxidation has been demonstrated as an efficient means for generating benzylic cations, allowing for the introduction

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

• approaches have diligently explored the details of reaction kinetics, quantitatively elucidating the impact of encapsulated Li+ on the reactivity of the outer fullerene cage as a specialized “encapsulated” Lewis acid catalyst [10][11]. While previous studies have revealed valuable insights, such as

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

• acceptors like 2b, which have acyl groups protecting the C6 position, the reaction kinetics become sluggish, resulting in low conversion rates or no conversion [36][39]. Results and Discussion In our studies, the initial glycosyl donors and acceptors (Figure 2; compounds 1a–g and 2a,b) were synthesized

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

• ). The reaction kinetics was evaluated in photocatalytic systems containing 0.025 mM of 1, since the amount of produced CO should be sufficient to be detected by GC-BID, even after a very short time from starting the reaction. As shown in Figure 5, in the first four hours, the formation of CO presents a

Benzoimidazolium-derived dimeric and hydride n-dopants for organic electron-transport materials: impact of substitution on structures, electrochemistry, and reactivity

• Swagat K. Mohapatra,
• Khaled Al Kurdi,
• Samik Jhulki,
• Georgii Bogdanov,
• John Bacsa,
• Maxwell Conte,
• Tatiana V. Timofeeva,
• Seth R. Marder and
• Stephen Barlow

Beilstein J. Org. Chem. 2023, 19, 1651–1663, doi:10.3762/bjoc.19.121

• spin resonance [14] or using dissociation and dimerization barriers from reaction kinetics and variable scan-rate electrochemistry, respectively [54]) and where F is the Faraday constant. Similarly, at least for cases where the reactive hydrides of 1H derivatives are ultimately lost as H2, the strength

Selective and scalable oxygenation of heteroatoms using the elements of nature: air, water, and light

• Damiano Diprima,
• Hannes Gemoets,
• Stefano Bonciolini and
• Koen Van Aken

Beilstein J. Org. Chem. 2023, 19, 1146–1154, doi:10.3762/bjoc.19.82

• on the rate than acids and bases and both the anion and cation appear to influence the reaction kinetics. A deliberate choice of salt can either significantly improve the kinetics or quench the reaction. The latter might be exploited e.g., in late-stage functionalization strategies in order to

C3-Alkylation of furfural derivatives by continuous flow homogeneous catalysis

• Grédy Kiala Kinkutu,
• Catherine Louis,
• Myriam Roy,
• Juliette Blanchard and
• Julie Oble

Beilstein J. Org. Chem. 2023, 19, 582–592, doi:10.3762/bjoc.19.43

• compared to [Ru3(CO)12] at 200 °C (Table 1, entries 3 and 4). This can be attributed, as mentioned above, to the slightly faster reaction kinetics of the [Ru3(CO)12] catalyst compared to that of comp1. Nevertheless, the better solubility of comp1 in toluene allows to get around the problems of

• as (pre)catalyst. These Ru(0) aggregates are therefore active, but the reaction kinetics are slower. While this observation is not a strict confirmation of our hypothesis regarding the formation of a monometallic complex, it is still consistent with it. Second optimization with a continuous flow

Heterogeneous metallaphotoredox catalysis in a continuous-flow packed-bed reactor

• Wei-Hsin Hsu,
• Susanne Reischauer,
• Peter H. Seeberger,
• Bartholomäus Pieber and
• Dario Cambié

Beilstein J. Org. Chem. 2022, 18, 1123–1130, doi:10.3762/bjoc.18.115

• efficiency of the nickel cycle in metallaphotoredox reactions. It is therefore not surprising that a larger acceleration of the reaction kinetics in flow versus batch was observed for the C–O coupling as opposed to the C–S coupling. Conclusion In summary, we developed a packed-bed reactor for

Automated grindstone chemistry: a simple and facile way for PEG-assisted stoichiometry-controlled halogenation of phenols and anilines using N-halosuccinimides

• Dharmendra Das,
• Akhil A. Bhosle,
• Amrita Chatterjee and
• Mainak Banerjee

Beilstein J. Org. Chem. 2022, 18, 999–1008, doi:10.3762/bjoc.18.100

• of mechanochemistry, Toda et al.’s “grindstone chemistry” [48] has also been proved as a useful technique for various organic transformations [49]. It is generally carried out by hand-grinding which is not only a labor-intensive process but also raises some concerns on the reaction kinetics

• through p-position leading to the formation of the thermodynamically stable halo derivative via a σ-complex formation. The high concentration of substrates and reagents in the close proximity in this solvent-less process and grinding force could be the other reasons for the fast reaction kinetics. The

• observed in the case of salicylic acids or anthranilic acids leading to 2,4,6-trihalo derivatives when 3 equiv of NXS were used. PEG-400 plays a key role for faster reaction kinetics and to afford better regioselectivity. Almost exclusive p-selectivity was observed for the aromatic substrates with free

Palladium-catalyzed solid-state borylation of aryl halides using mechanochemistry

• Koji Kubota,
• Emiru Baba,
• Tamae Seo,
• Tatsuo Ishiyama and
• Hajime Ito

Beilstein J. Org. Chem. 2022, 18, 855–862, doi:10.3762/bjoc.18.86

• faster reaction kinetics than those under conventional solution-based conditions because of the high concentration; further, the experimental operations can be carried out in air. Considering these achievements, including our recent success in solid-state cross-coupling chemistry, we envisioned that this

Structural basis for endoperoxide-forming oxygenases

• Takahiro Mori and
• Ikuro Abe

Beilstein J. Org. Chem. 2022, 18, 707–721, doi:10.3762/bjoc.18.71

• showed similar reaction kinetics and verruculogen productivity to those of wild type FtmOx1. Interestingly, the Y68F variant generated an unidentified product, which was recently determined to be 26-hydroxyverruculogen [75]. Based on these observations, they proposed an alternative reaction mechanism. In