Search results
Search for "reactions" in Full Text gives 3163 result(s) in Beilstein Journal of Organic Chemistry. Showing first 200.
An Fe(II)-catalyzed synthesis of spiro[indoline-3,2'-pyrrolidine] derivatives
Beilstein J. Org. Chem. 2025, 21, 2383–2388, doi:10.3762/bjoc.21.183
- categorized into two main approaches. The first involves cascade reactions featuring the formation of multiple bonds, including a pivotal spirocyclization step. However, these strategies typically require pre-functionalized starting materials and often result exclusively in substituted oxindoles. For example
Conformational effects on iodide binding: a comparative study of flexible and rigid carbazole macrocyclic analogs
Beilstein J. Org. Chem. 2025, 21, 2369–2375, doi:10.3762/bjoc.21.181
- ) and WDG (rigid fluorene backbone), were synthesized via Friedel–Crafts reactions. Their iodide (I−) recognition properties were systematically explored using 1H NMR, UV–vis absorption, and fluorescence spectroscopy. Quantitative analysis via the Benesi–Hildebrand equation and nonlinear fitting
Adaptive experimentation and optimization in organic chemistry
Beilstein J. Org. Chem. 2025, 21, 2367–2368, doi:10.3762/bjoc.21.180
- . provide a comprehensive review of machine learning applications in enantioselective organocatalysis, highlighting both achievements and remaining challenges [10]. Guo et al. present an automated flow chemistry system for nitration reactions, combining kinetic modeling with experimental optimization [11
Rotaxanes with integrated photoswitches: design principles, functional behavior, and emerging applications
Beilstein J. Org. Chem. 2025, 21, 2345–2366, doi:10.3762/bjoc.21.179
- bulky stoppers at both ends to prevent dethreading (Figure 1) [1][8]. Functionalization of the axle with recognition sites allows the macrocycle to shuttle between positions in response to external stimuli, including light, redox, temperature, pH, and reactions with chemicals such as carbodiimides [9
- experimental and theoretical studies involving these rotaxanes showed that no side reactions occur upon excitation, meaning these compounds can be operated continuously under illumination with very little efficiency loss, making them very effective photoactive units in nanodevices. In 2005, Leigh and co
- delivery and microscale chemical reactions, by allowing the controlled merging of droplets containing different reactants without the need for traditional reaction vessels. Furthermore, Zhu and co-workers developed a rotaxane-based fluorescence switch in which photoinduced shuttling of the benzylic amide
Comparative analysis of complanadine A total syntheses
Beilstein J. Org. Chem. 2025, 21, 2334–2344, doi:10.3762/bjoc.21.178
- diastereomers) via either a creative “degradation” of the piperidine ring or cross-coupling reactions at the pyridine C3 position [29]. The Tsukano total synthesis – 2013 In 2013, Tsukano and co-workers reported their total synthesis of complanadines A and B (Scheme 4). Their synthesis utilizes a Diels–Alder
Recent advances in Norrish–Yang cyclization and dicarbonyl photoredox reactions for natural product synthesis
Beilstein J. Org. Chem. 2025, 21, 2315–2333, doi:10.3762/bjoc.21.177
- Peng-Xi Luo Jin-Xuan Yang Shao-Min Fu Bo Liu College of Chemistry, Sichuan University, 29 Wangjiang Rd., Chengdu, Sichuan 610064, China 10.3762/bjoc.21.177 Abstract In recent years, the Norrish–Yang cyclization and related photoredox reactions of dicarbonyls have been extensively utilized in
- natural product synthesis. This review summarizes the latest advancements in these reactions for constructing terpenoids, alkaloids, and antibiotics. Through Norrish–Yang cyclization, dicarbonyls (e.g., 1,2-diketones and α-keto amides) can efficiently construct sterically hindered ring structures, which
- can further undergo ring-opening or rearrangement reaction to assemble complex molecular frameworks. Additionally, quinone photoredox reactions involving single-electron transfer (SET) processes provide novel strategies for the stereoselective synthesis of useful structures such as spiroketals. This
Insoluble methylene-bridged glycoluril dimers as sequestrants for dyes
Beilstein J. Org. Chem. 2025, 21, 2302–2314, doi:10.3762/bjoc.21.176
- -surfaces and which are activated for electrophilic aromatic substitution reactions. For the synthesis of W1, we initially prepared tetramethoxybiphenyl 1 (Scheme 1) according to the literature procedure involving the Suzuki coupling between 3,4-dimethoxybromobenzene and 3,4-dimethoxyphenylboronic acid [44
Halogenated butyrolactones from the biomass-derived synthon levoglucosenone
Beilstein J. Org. Chem. 2025, 21, 2297–2301, doi:10.3762/bjoc.21.175
- reactions for 5 to give substrates for the Baeyer–Villiger oxidation resulting in halogenated butyrolactones, which is an unexplored chemical space for this biomass derivative. Results and Discussion The halogenated LGO derivatives 7a and 7b were prepared using literature procedures [22][23]. The reaction
- in 22% yield. Fluorination of α,β-unsaturated ketones is a more challenging transformation than the halogenation reactions presented in Scheme 1 [33]. The previous reports of enamines as suitable substrates led us to prepare and examine enamine 15, which was generated from 5 with 3.0 equivalents of
- electrophilic fluorine in the best case gave 15% conversion for NFSI and less than 8% isolated yield of 7c for SF. The major product in these reactions was 5, due to a β-elimination of the amine. In comparison, the reaction of 15 with NBS afforded 7b in an unoptimized yield of 48% after hydrolysis, which
Enantioselective radical chemistry: a bright future ahead
Beilstein J. Org. Chem. 2025, 21, 2283–2296, doi:10.3762/bjoc.21.174
- Anna C. Renner Sagar S. Thorat Hariharaputhiran Subramanian Mukund P. Sibi Department of Chemistry and Biochemistry, North Dakota State University, Fargo, North Dakota, 58105-5516, USA 10.3762/bjoc.21.174 Abstract This perspective is focused on enantioselective free radical reactions. It
- describes several important catalytic asymmetric strategies applied to enantioselective radical reactions, including chiral Lewis acid catalysis, organocatalysis, photoredox catalysis, chiral transition-metal catalysis and photoenzymatic catalysis. The application of electrochemistry to asymmetric radical
- the 1990s. Since then, meticulous research by several research groups has led to significant advances in this area [4][5][6][7][8]. This perspective focuses on several important contributions to the science of asymmetric radical reactions. Pioneering work on chiral Lewis acid catalysis and iminium
Pathway economy in cyclization of 1,n-enynes
Beilstein J. Org. Chem. 2025, 21, 2260–2282, doi:10.3762/bjoc.21.173
- importance of reducing the time required for reaction processes and conducting multistep reactions within a single pot (Scheme 1a) [6][7]. Contemporary organic synthesis is progressively approaching ideal synthesis – achieving highly functionalized target molecular frameworks in a single step. This paradigm
- components such as solvents, catalysts, ligands and so on. Unlike traditional “one-to-one” reactions, pathway-controlled “one-to-many” transformations synthesize multiple products from single intermediates, dramatically reducing preparation time and reagent requirements (Scheme 1b). As an exceptionally
- could be further derivatized (e.g., via borylation, epoxidation), establishing a versatile platform for accessing fused-ring natural products. Substituent-controlled cyclization of 1,n-enynes In transition metal-catalyzed cyclization reactions, the electronic properties and steric hindrance of
Research towards selective inhibition of the CLK3 kinase
Beilstein J. Org. Chem. 2025, 21, 2250–2259, doi:10.3762/bjoc.21.172
- -bromo-5-chloroaniline (2b). Next, we prepared the final targets by Suzuki-type reactions using the aromatic bromides 7. As indicated before, the acid function designed to interact with the lysine 241 has been introduced both in para and meta positions of the aromatic linker. Further we have prepared two
A chiral LC–MS strategy for stereochemical assignment of natural products sharing a 3-methylpent-4-en-2-ol moiety in their terminal structures
Beilstein J. Org. Chem. 2025, 21, 2243–2249, doi:10.3762/bjoc.21.171
- followed by ozonolysis to generate 3-((4-bromobenzoyl)oxy)-2-methylbutanoic acid. The four stereoisomers of this fragment were prepared through two separate Evans aldol reactions, each affording a pair of diastereomers. The final four stereoisomers were resolved by chiral HPLC (CHIRALPAK IA column with
Pd-catalyzed dehydrogenative arylation of arylhydrazines to access non-symmetric azobenzenes, including tetra-ortho derivatives
Beilstein J. Org. Chem. 2025, 21, 2234–2242, doi:10.3762/bjoc.21.170
- efficacious but face significant challenges when applied to non-symmetric systems [24], particularly in achieving regioselectivity. These methods frequently require a particular reagent pair or an excess of one reactant, which limits their efficiency and versatility. In contrast, Baeyer–Mills reactions, which
- intricate and inefficient using these standard synthetic protocols. The transition-metal-catalyzed C–N bond formation has emerged as a viable route to access non-symmetric azobenzenes, owing to the broad functional group tolerance of Buchwald–Hartwig amination reactions [34][35][36][37][38][39][40]. Kong
- bromotoluene (Table 1, entries 5–8). For subsequent optimizations, we selected t-BuXPhos for practical reasons, as it is less sensitive to oxidative conditions. Further optimization revealed that Cs2CO3 is more efficient than NaH for this reaction (Table 1, entry 9). However, reactions conducted with a new
Thiadiazino-indole, thiadiazino-carbazole and benzothiadiazino-carbazole dioxides: synthesis, physicochemical and early ADME characterization of representatives of new tri-, tetra- and pentacyclic ring systems and their intermediates
Beilstein J. Org. Chem. 2025, 21, 2220–2233, doi:10.3762/bjoc.21.169
- spectrometer equipped with a Direct Insertion Probe (EI+ ionization) or on a Bruker Q-TOF Maxis Impact mass spectrometer (ESI+ ionization) coupled with a Waters Acquity I-Class UPLC system equipped with a diode array detector. The reactions were followed by analytical thin-layer chromatography on silica gel 60
Synthesis of triazolo- and tetrazolo-fused 1,4-benzodiazepines via one-pot Ugi–azide and Cu-free click reactions
Beilstein J. Org. Chem. 2025, 21, 2202–2210, doi:10.3762/bjoc.21.167
- advantages over traditional copper-catalyzed azide–alkyne cycloaddition (CuAAC) reactions, including operational simplicity and the absence of metal contaminants, which is crucial for pharmaceutical applications. After having identified suitable reaction conditions of the Ugi–azide and click reactions for
- . However, the reaction of 2-azido-5-bromobenzaldehyde (1d) gave only a trace amount of product 8h. Instead, compound 8h', an intermediate without lactamization, was isolated in 59% yield. It is likely that the bromo group on the phenyl ring interfered with the lactamization process. Two control reactions
- of compounds 6a (red) and 8a (blue). Ugi–azide reaction for the synthesis of 1,5-DS-T-containing heterocycles. Proposed Ugi–azide-initiated synthesis of polyheterocyclic scaffolds 7 and 8. 4-CR vs stepwise Ugi–azide reactions for the synthesis of 7a. Synthesis of benzodiazepines 7a–k. Reaction
Electrochemical cyclization of alkynes to construct five-membered nitrogen-heterocyclic rings
Beilstein J. Org. Chem. 2025, 21, 2173–2201, doi:10.3762/bjoc.21.166
- reactions of alkynes towards five-membered rings are classified and presented in detail. Based on different types of five-membered rings, electrochemical construction of indoles, isoindolinones, indolizines, oxazoles, imidazoles, pyrroles, imidazoles and 1,2,3-triazoles are summarized and the possible
- electricity to promote a reaction grew up gradually [56][57][58][59][60][61][62][63][64][65][66][67][68][69][70][71][72][73][74]. In the past decades, the electrochemical organic reactions [75][76][77][78][79][80][81][82][83][84][85][86][87][88] which utilized an external applied voltage to accelerate
- electrochemical annulation of alkynes with enamides. Electrochemical [3 + 2] cyclization of heteroarylamine was an efficient access towards imidazopyridine. The electrochemical oxidative [3 + 2] cycloaddition of secondary propargyl alcohol produced 1,2,3-triazole. In most of these above reactions, the target
C2 to C6 biobased carbonyl platforms for fine chemistry
Beilstein J. Org. Chem. 2025, 21, 2103–2172, doi:10.3762/bjoc.21.165
- at illustrating how the chemistry of biobased carbonyl platform molecules with backbones from C2 to C6 offers opportunities to reach all kinds of chemical architectures, sometimes even complex ones benefiting from the ability of the carbonyl group to be involved in multicomponent reactions. Keywords
- synthesis of amines by replacing the current toxic pathway based on ethylene oxide and dichloroethane [29]. Due to the high reactivity of α-hydroxycarbonyls, the main issue in this reductive amination reaction [30] was to control the cascade of consecutive and parallel reactions. The use of methanol as
- avoid side reactions and promoted exclusive transformation of formaldehyde into glycolic acid. The use of E. coli K-12 strains as host cells and paraformaldehyde as the starting material, led to production of GA with high conversion even at rather high concentrations (Scheme 8) [36]. Using a CuII-based
The application of desymmetric enantioselective reduction of cyclic 1,3-dicarbonyl compounds in the total synthesis of terpenoid and alkaloid natural products
Beilstein J. Org. Chem. 2025, 21, 2085–2102, doi:10.3762/bjoc.21.164
- cyclic prochiral dicarbonyl substrates. In addition, various approaches could be used for the desymmetrization reactions such as enzyme catalytic-, organocatalyst-, and transition-metal-catalyzed reductions [5][6][7]. Advance about the synthesis of several terpenoid and alkaloid natural products (1–5
- -cyclopentanedione derivative was adopted as one of the key reactions, which facilitated the construction of the five-membered ring bearing an all-carbon quaternary center as the key chiral building block. Their synthesis began with 1,3-dione 40 (Scheme 2) [31][32], allylation of this substrate with allylic bromide
Multicomponent reactions IV
Beilstein J. Org. Chem. 2025, 21, 2082–2084, doi:10.3762/bjoc.21.163
- National Academy of Sciences of Ukraine, Nauky Av. 60, 61072 Kharkiv, Ukraine, Faculty of Chemistry, V. N. Karazin Kharkiv National University, Svobody Sq. 4, 61077 Kharkiv, Ukraine 10.3762/bjoc.21.163 Keywords: multicomponent reactions; The synthesis of complex molecules is a cornerstone of modern
- optimization of promising lead structures has therefore inspired the development of powerful synthetic strategies. A glance at Web of Science reveals that one-pot methods and multicomponent reactions (MCRs) [1] have attracted steadily increasing attention within the scientific community over the past 25 years
- (Figure 1). According to a quick Web of Science [2] keyword search of "multicomponent reaction" and "one-pot reaction" (Figure 1A) and "multicomponent reaction" (Figure 1B) filtered by publication year, the impressive sum of 136,658 publications on multicomponent (Figure 1A) and one-pot reactions and
Discovery of cytotoxic indolo[1,2-c]quinazoline derivatives through scaffold-based design
Beilstein J. Org. Chem. 2025, 21, 2062–2071, doi:10.3762/bjoc.21.161
- )-one scaffold 1 was synthesized according to the optimized protocol developed by Bergman et al. [9]. Position 12 of indolo[1,2-c]quinazolin-6(5H)-one (1) (Scheme 1) corresponded to of the indole C3 position, which is typically used as a nucleophilic center for functionalization via reactions with
- introduce the carboxylic acid group a sequence of formylation/oxidation reactions was used. Vilsmeier–Haack reaction of 1 afforded 6-oxoindolo[1,2-c]quinazoline-12-carbaldehyde (2) (Scheme 1). All attempts to oxidize the aldehyde group of 2 to the corresponding carboxylic acid were hampered by the oxidative
Bioinspired total syntheses of natural products: a personal adventure
Beilstein J. Org. Chem. 2025, 21, 2048–2061, doi:10.3762/bjoc.21.160
- capability have been increasing all the time by discovering and inventing a vast number of new organic reactions and methodologies [6]. However, could mankind become really stronger than Mother Nature one day? This question seems to have no answer as future is unpredictable. Maybe, Mother Nature could be our
- , monocerin and 12-hydroxymonocerin were presumably generated from their corresponding precursors through similar oxidation and oxa-Michael addition reactions. Given the fact that quinone methides served as a powerful platform for the development of rich useful organic transformations, especially, through
- underwent dehydroxylation protocol involving base-promoted mesylate elimination and catalytic hydrogenation reactions, providing 31a. Reduction of lactam and ester in one pot with LiAlH4 and acid-promoted hydrolysis of ketal protection to ketone furnished 32a. Finally, oxidation of the primary alcohol to
Switchable pathways of multicomponent heterocyclizations of 5-amino-1,2,4-triazoles with salicylaldehydes and pyruvic acid
Beilstein J. Org. Chem. 2025, 21, 2030–2035, doi:10.3762/bjoc.21.158
- , 61072, Kharkiv, Ukraine Enamine Ltd., Winston Churchill Street 78, Kyiv 02094, Ukraine Faculty of Chemistry, V. N. Karazin Kharkiv National University, Svobody sq., 4, 61022, Kharkiv, Ukraine 10.3762/bjoc.21.158 Abstract Switchable multicomponent reactions involving 3-substituted-5-amino-1,2,4
- -triazoles, pyruvic acid, and salicylaldehydes were studied under different conditions. Upon conventional heating, benzotriazolooxadiazocine-5-carboxylic acids were formed in the three-component reactions as single reaction products. Upon ultrasonic activation or mechanical stirring at room temperature, the
- multicomponent reaction of the same starting materials led to the formation of only tetrahydrotriazolopyrimidine derivatives. Keywords: 5-amino-1,2,4-triazole; heterocyclization; multicomponent reaction; salicylaldehyde; ultrasonication; Introduction Multicomponent reactions (MCRs) are a powerful tool for the
α-Ketoglutaric acid in Ugi reactions and Ugi/aza-Wittig tandem reactions
Beilstein J. Org. Chem. 2025, 21, 2021–2029, doi:10.3762/bjoc.21.157
- ; quinoxalinone derivative; Ugi reaction; Introduction Multicomponent reactions are powerful tools in organic chemistry that enable the synthesis of structurally complex and multifunctional compounds from three or more starting materials in a single synthetic step. They are widely used in drug discovery because
- reactions, widely used as a green alternative for the synthesis of active pharmaceutical ingredients [7] and opens up the possibility of creating new compounds from the class of peptidomimetics [8][9][10], which often exhibit diverse biological effects [11] including antidiabetic [12], antiviral [13
- for the preparation of benzodiazepinone derivatives, which showed promising psychotropic effects [20][21][22][23][24], using a tandem combination of Ugi/azide–alkyne cycloaddition reactions. From this point of view, azido amines are promising reagents for use in the Ugi reaction, opening up the
Understanding the origin of stereoselectivity in the photochemical denitrogenation of 2,3-diazabicyclo[2.2.1]heptene and its derivatives with non-adiabatic molecular dynamics
Beilstein J. Org. Chem. 2025, 21, 2007–2020, doi:10.3762/bjoc.21.156
- Leticia A. Gomes Steven A. Lopez Department of Chemistry and Chemical Biology, Northeastern University, Boston, Massachusetts, 02115, United States 10.3762/bjoc.21.156 Abstract Photochemical denitrogenation reactions of bicyclic azoalkanes produce strained bicyclic compounds of interest to
- synthetic organic chemists. We report a computational study on the mechanism of diazabicyclo[2.2.1]heptenes to address long standing mechanistic questions. Indeed, the mechanism of these reactions has been disputed for over six decades. We employed non-adiabatic molecular dynamics (NAMD) simulations
- ; stereoselectivity; Introduction Photochemical reactions utilize light as a sustainable energy source and are considered to be ‘green’ reactions [1][2]. Organic chromophores absorb light, accessing higher-lying excited state(s) that exhibit distinct reactivities, leading to bond breaking and formation, irreversibly
Measuring the stereogenic remoteness in non-central chirality: a stereocontrol connectivity index for asymmetric reactions
Beilstein J. Org. Chem. 2025, 21, 1995–2006, doi:10.3762/bjoc.21.155
- remained an intuitive and empirical practice, particularly for reactions that create non-central chirality. We put forward a stereocontrol connectivity index to parameterize asymmetric reactions according to the bond connectivity relationships between the prochiral stereogenic elements, the reactive sites
- , and the stereochemical-defining substituents. The indices can be generated based on analysis of the chemical structures of the starting materials and products, without mechanistic insights of the transformation. Representative examples of reactions that establish point chirality, axial chirality
- chiral molecules. Keywords: asymmetric reactions; axial chirality; catalysis; planar chirality; stereocontrol; Introduction Chirality is a ubiquitous and fundamental phenomenon in nature and thus holds an irreplaceable position in organic synthesis. At its most rudimental definition, chirality in a
Other Beilstein-Institut Open Science Activities
