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Search for "catalyst" in Full Text gives 1867 result(s) in Beilstein Journal of Organic Chemistry. Showing first 200.
Total syntheses of highly oxidative Ryania diterpenoids facilitated by innovations in synthetic strategies
Beilstein J. Org. Chem. 2025, 21, 2553–2570, doi:10.3762/bjoc.21.198
- reaction with allyltributylstannane, yielding compound 40. After isomerization of the C11 allyl double bond and introduction of a C6 isobutenyl group, the resulting diene 42 underwent RCM catalyzed by the Hoveyda–Grubbs catalyst to form the pentacyclic skeleton 43, thus completing the C ring of the natural
- deprotection and ester hydrolysis produced carboxylic acid 101, which upon oxidative dearomatization yielded dienone 102, thus completing the D-ring. Regioselective epoxidation to 103 and reduction (using Adams' catalyst) through intermediate 104 gave lactone 105. A retro-oxa-Michael/intramolecular
Palladium-catalyzed regioselective C1-selective nitration of carbazoles
Beilstein J. Org. Chem. 2025, 21, 2479–2488, doi:10.3762/bjoc.21.190
- substrate, using silver nitrate as the nitrating agent (Table 1). After detailed optimization studies, we found that the treatment of 1a with AgNO3 in the presence of Pd2(dba)3 as the catalyst in 1,4-dioxane afforded the desired C1-nitrated product 2a in 69% isolated yield (Table 1, entry 1). Product 2a was
- failed to enhance the product 2a yield (Table 1, entry 10). Attempts to optimize the reaction temperature did not yield improvements either (Table 1, entry 11). Control experiments confirmed that both the palladium catalyst and AgNO3 are essential for the reaction to proceed, as omission of either
- palladacycle 6 as the catalyst, and the desired nitrated product 2a was obtained in 48% yield (Scheme 5c). This result supports the involvement of palladacycle intermediate 6 in the catalytic cycle. Proposed mechanism Based on our experimental results and related literature precedents [68][69][74][75][76][77
Synthesis of the tetracyclic skeleton of Aspidosperma alkaloids via PET-initiated cationic radical-derived interrupted [2 + 2]/retro-Mannich reaction
Beilstein J. Org. Chem. 2025, 21, 2470–2478, doi:10.3762/bjoc.21.189
- ] gave the desired product 10a, with catalyst I giving the best result (Table 1, entries 1–3). The necessities of irradiation and the presence of a photocatalyst were also defined (Table 1, entries 4 and 5). However, use of the other tested catalysts did not give the desired product under the reaction
- conditions (see Supporting Information File 1 for details). Next, we evaluated the effects of different solvents on the production of 10a in the presence of catalyst I. Changing the solvent to MeOH, tetrahydrofuran (THF), and dichloromethane (DCM) resulted in decreased yields and substrate conversions, and
Ex-situ generation of gaseous nitriles in two-chamber glassware for facile haloacetimidate synthesis
Beilstein J. Org. Chem. 2025, 21, 2465–2469, doi:10.3762/bjoc.21.188
- trichloroacetimidates K2CO3 was effective for the synthesis of β-acetimidates [26], whereas polystyrene-supported DBU [27] was found to be less effective and DBU was therefore the preferred catalyst. The synthesis of perbenzylated α-glucosyl trifluoroacetimidate 3 proceeded in 52% yield on a preparative scale, with DBU
The intramolecular stabilizing effects of O-benzoyl substituents as a driving force of the acid-promoted pyranoside-into-furanoside rearrangement
Beilstein J. Org. Chem. 2025, 21, 2456–2464, doi:10.3762/bjoc.21.187
- (Figure 1) [19]. The introduction of an alkyl or aryl substituent in the anomeric center prevents free interconversion between pyranose and furanose forms; however, this transformation can still occur under specific conditions, typically in the presence of an acid catalyst. Even under such conditions, the
Catalytic enantioselective synthesis of selenium-containing atropisomers via C–Se bond formations
Beilstein J. Org. Chem. 2025, 21, 2447–2455, doi:10.3762/bjoc.21.186
- pathway. In both pathways, the active chiral rhodium catalyst is regenerated through a silver salt-mediated recycling, with Ag–SePh being formed as a byproduct (Scheme 2). 2. Catalytic atroposelective synthesis of selenium-containing atropisomers by spontaneous selenosulfonylation of alkynes Vinyl
- or cationic species. In 2019, Qin and co-workers reported a methodology enabling the difunctionalization of alkynes through selenosulfonylation of a VQM intermediate under mild reaction conditions [20]. This racemic transformation proceeds without the need for any catalyst or additive, and the
- reaction yielded the desired product at room temperature with high regioselectivity and stereoselectivity (E/Z ratio >99:1). Notably, when chiral catalyst (cat.1) was used, the reaction afforded the axially chiral product 9 in 43% yield with 84% ee. The proposed mechanism proceeds as follows. Catalyst cat
Transformation of the cyclohexane ring to the cyclopentane fragment of biologically active compounds
Beilstein J. Org. Chem. 2025, 21, 2416–2446, doi:10.3762/bjoc.21.185
- ] using Co(II) catalyst 113, in the presence of PhSiH3, TsCl in MeOH resulted in the formation of a cyclopentenone derivative 111 with a yield of 43% and a small amount (<5%) of cyclopentenone derivative 112. The remaining mass balance consisted mainly of the recovered starting material. Demethylation of
- (±)-terretonin L (109) as the main product with a yield of 46%. Radical hydrochlorination of olefin 110 under more powerful oxidizing conditions (Co(II) catalyst 113, N-fluoropyridinium salt (F+) 114), resulted in the formation of cyclopentenone derivative 112 with a yield of 90%. Demethylation of the latter led
- completed by converting the exocyclic methyl ester 144 to an aldehyde145 using a one-pot DIBAL-H/Dess–Martin procedure followed by the removal of TMS protecting group using a stoichiometric Wilkinson’s catalyst (Scheme 25). The authors noted that, in the final stages of reduction and oxidation, yields were
The high potential of methyl laurate as a recyclable competitor to conventional toxic solvents in [3 + 2] cycloaddition reactions
Beilstein J. Org. Chem. 2025, 21, 2389–2415, doi:10.3762/bjoc.21.184
- functionality have been observed to exhibit notable trans diastereoselectivity in the context of cycloaddition reactions [130][131][132][133][134][135]. For this purpose, equivalent amounts of nitrone 1a and maleimide 2a were reacted with 5 mol % catalyst (Table 5) under the cycloaddition conditions determined
- of the relevant catalysts, it was found that these catalyst molecules had no significant effect on the cis/trans diastereoisomer distribution. Conclusion In conclusion, the present study reveals that methyl laurate is an excellent biocompatible solvent candidate for [3 + 2] cycloaddition reactions
- (cis + trans isomers). Catalyst survey for the synthesis of 3a (cis + trans isomers). Supporting Information Supporting Information File 4: Characterization data, copies of NMR spectra, additional Table and Figures. Funding We gratefully acknowledge the Bursa Uludağ University Scientific Research
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
- -fumaramide showed stereoselectivity. Upon photoswitching to the cis isomer, the macrocycle moved to the thiodiglycolamide site, which disrupted its ability to catalyze the reaction, leading to the loss of stereoselectivity. This work represents the first evidence of a light-responsive interlocked catalyst
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
- , followed by diastereoselective α-alkylation, produced 38. A Wittig reaction and subsequent deketalization converted the ketone in 38 to the terminal alkene 39, allowing for subsequent sequential chemoselective hydrogenations: first, hydrogenation of the exo-olefin using Wilkinson’s catalyst proceeded with
Insoluble methylene-bridged glycoluril dimers as sequestrants for dyes
Beilstein J. Org. Chem. 2025, 21, 2302–2314, doi:10.3762/bjoc.21.176
- reaction of methylene-bridged glycoluril dimer G2BCE with aromatic walls W1–W4 conducted in trifluoroacetic acid (TFA) as both solvent and acid catalyst. The new hosts G2W1–G2W4 were obtained in 28, 33, 59, and 62% yield, respectively, after washing and recrystallization processes. Hosts G2W1–G2W4 are
Enantioselective radical chemistry: a bright future ahead
Beilstein J. Org. Chem. 2025, 21, 2283–2296, doi:10.3762/bjoc.21.174
- include the use of transition metals or photoredox catalysts. In photoredox catalysis, radical generation often involves single-electron transfer (SET) to or from a photoexcited state of a photoredox catalyst, usually a metal complex or organic molecule. Two other notable strategies for radical generation
- obviating the need for both enantiomers of the ligand. Although chiral Lewis acid-mediated radical reactions were groundbreaking, they suffered from major disadvantages: (a) high catalyst loadings (stoichiometric or sub-stoichiometric), (b) large amounts of the radical initiator, (c) the need for a large
- applied in the development of enantioselective polyene cyclizations, which demonstrated the power of the catalytic strategy. In the presence of a chiral amine catalyst 16 (Scheme 3) and the mild oxidant Cu(OTf)2, polyenes with a terminal aldehyde group underwent intramolecular cyclizations affording
Pathway economy in cyclization of 1,n-enynes
Beilstein J. Org. Chem. 2025, 21, 2260–2282, doi:10.3762/bjoc.21.173
- systematically regulating reaction parameters (solvent, substituent, ligand, catalyst) in 1,n-enyne cyclizations, enabling efficient "one-to-many" transformations that drastically reduce synthetic steps and resource consumption. Review Solvent-controlled cyclization of 1,n-enynes Solvents play a multifaceted
- solvent-controlled selective syntheses of two polycyclic compounds (Scheme 6) [13]. Using PdCl2 as the catalyst and DMF as the solvent, substrate 22 underwent a 6-endo-dig cyclization and subsequent enone insertion, forming a palladium–carbon bond intermediate. Protonolysis yielded isocoumarin-fused
- afforded selective access to four indole derivatives through modulation of the alkyne's terminal substituents and nucleophile type (Scheme 14) [21][22]. The gold(I) catalyst activated the unsubstituted terminal alkynes to initiate a 5-exo-dig cyclization, generating a spiro[indoline-3,3'-pyrrolidine
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
- synthesis [18][19][20][21]. Sudhakara et al. described the advantages of using bismuth nitrate as catalyst in the synthesis of hydrazones and in the one-pot Fischer synthesis of indoles from ketones and hydrazines [22][23]. Adopting this method, hydrazone intermediates 7a–j were obtained by treatment of
- hydrazino derivatives 5a,b with ketones 6a–e in the presence of bismuth nitrate pentahydrate catalyst in refluxing methanol with good to excellent yields (method A, step 1). As regards cis–trans isomerism, compounds (E)-7a and (E)-7f were isolated in high yields (94% and 84%, respectively), however, in the
- were previously used for the synthesis of 7-nitroindole derivatives: heating in polyphosphoric acid (PPA) at 80 °C [24][25]. However, our attempt was not successful. Experiments with zinc chloride, the most commonly used Lewis acid catalyst in Fischer indole syntheses, also failed under various
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
- access triazole-fused and tetrazole-tethered benzodiazepines 7 via Ugi–azide/intramolecular click reaction under Cu-catalyst-free conditions. The 4-CR Ugi–azide reaction was modified to be a one-pot two-step reaction process to address functional group compatibility issues. By using 2-isocyanoacetate
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
- ]. Besides, electrochemical cyclization of alkynes is also an important access towards indoles. In 2016, Xu reported the electrochemical intramolecular coupling of urea derivatives to form substituted indoles (Scheme 1) [162]. Using [Cp2Fe] (5 mol %) as the redox catalyst, the intramolecular coupling of
- -metal catalyst and oxidant, was an economic and efficient protocol compared with the previous method [174][175][176][177][178][179][180][181][182][183][184]. The ruthenium-accelerated electrochemical dehydrogenative annulation of alkyne with an aniline derivative was also an efficient method to build
- for 6 h. The authors also proposed the reaction mechanism on basis of experimental results and previous literature [205][206]. Firstly, the ligand exchange between (R)-Rh1 and n-Bu4NOAc or 1-AdCO2H gave a chiral active catalyst A. The irreversible base-prompted C–H activation of A with 19a yielded a
C2 to C6 biobased carbonyl platforms for fine chemistry
Beilstein J. Org. Chem. 2025, 21, 2103–2172, doi:10.3762/bjoc.21.165
- solvent and Pd as catalyst played a vital role for achieving a high yield. Efficient subsequent esterification and quaternarization to diesterquat fabric softeners demonstrated that high-value chemicals could be produced fully biobased from GCA as the starting platform (Scheme 2). GCA can also be used as
- a C1 building block for the N-formylation of secondary amines to formamides under catalyst-free conditions and air as oxidant. This method was applied to different aromatic and aliphatic (both cyclic and acyclic) amines (Scheme 3) [31]. Already in 1955, Parham and Reiff reported the synthesis and
- electrocatalyst supported on nitrogen-doped carbon nanosheets (Cu/NCNSs). This catalyst exhibits high activity for the oxidation of various substrates, including GLY, gluconic acid (GLU), 5-hydroxymethylfurfural (HMF), benzyl alcohol (BA), furfuryl alcohol (FA), and ethylene glycol (EG) (Scheme 7) [35]. Park et
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
- reduction of diketone 28 for preparing alcohol 30 under the CBS conditions [8] with (S)-29 as the catalyst (Scheme 1) [14]. Notably, this reaction could be performed on multiple gram scales with satisfactory yield (72%) and ee value (92%). Protection of the alcohol group in 30 with TBSCl followed by
- and transformations of 43 produced hydroxyketone 44. Due to the steric hindrance of this substrate, the subsequent Suzuki cross coupling reaction with 3-boronophenol proceeded in low yield. To address this issue, Han′s group employed a novel palladacycle catalyst 45, previously developed by their
- ], the enzyme-catalyzed desymmetric enantioselective reduction of 28, afforded hydroxyketone 54 in 65% yield with >99% ee and 8–9:1 dr on multigram scale [34]. Functional group transformations of 54 in four steps produced sterically hindered allyl triflate 55. By employing the palladacycle catalyst 45
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
- , planar chirality, and “inherent chirality” are illustrated using the stereocontrol connectivity index produced following a unified 3-step process. Application of such stereochemical classification could facilitate the development of new synthetic methodologies and catalyst systems to construct diverse
- substituents. Intuitively, the intrinsic spatial separation among prochiral stereogenic elements, the reactive sites, and the stereochemical-defining substituents makes stereoinduction for non-central chirality using a chiral catalyst or reagent particularly challenging. However, a quantitative
- –B [14] (Scheme 3E) bonds. In the case of an asymmetric cross-coupling reaction (Scheme 3C) [10], both sets of the substituents on individual aryl groups are considered because neither is involved in the bond formation/cleavage. Accordingly, the catalyst-controlled atroposelective Suzuki–Miyaura
Aryl iodane-induced cascade arylation–1,2-silyl shift–heterocyclization of propargylsilanes under copper catalysis
Beilstein J. Org. Chem. 2025, 21, 1984–1994, doi:10.3762/bjoc.21.154
- techniques, indicating that the observed arylation–cyclization cascade reaction is highly stereospecific. With this result in hand, we performed copper catalyst screening (Table 3). We observed that CuCl and the CuOTf benzene complex gave similarly good yields (82–84% by NMR, Table 3, entries 2 and 4), while
- the CuBF4 acetonitrile complex was the next best choice (77% by NMR, Table 3, entry 5). Heterogenous catalysis using Cu2O gave a mixture of the arylated product 8a and protodecupration side-product 12, both in poor yields (Table 3, entry 6). Increased catalyst loading (11 mol % of [CuOTf]2∙PhH
- ) resulted in the formation of more side products (Table 3, entry 9), and we therefore decided to proceed with 5 mol % of the catalyst for the substrate scope. We also observed that, in the absence of base, even at room temperature, only the protodecupration product 12 was obtained (with up to 69% NMR yield
Photochemical reduction of acylimidazolium salts
Beilstein J. Org. Chem. 2025, 21, 1973–1983, doi:10.3762/bjoc.21.153
- transition-metal complexes such as the Grubbs’ second-generation metathesis catalyst, NHCs are now also well-established as organocatalysts. With the first application pre-dating the unambiguous characterization of a free NHC by nearly 50 years, NHCs can facilitate numerous synthetically attractive
- represents an actual chemical yield of 30%. While seemingly less efficient than the photoredox process, the successful generation of reduced species in the absence of the catalyst is a remarkable result that highlights the unique influence of the NHC fragment on the reduction potentials and photoreactivity
Asymmetric total synthesis of tricyclic prostaglandin D2 metabolite methyl ester via oxidative radical cyclization
Beilstein J. Org. Chem. 2025, 21, 1964–1972, doi:10.3762/bjoc.21.152
- -metathesis reaction smoothly in the presence of the Hoveyda–Grubbs second-generation catalyst to afford the enone 13 in 63% yield with the desired trans-configuration. Enone 13 was then subjected to the Pd/C-catalyzed hydrogenation to give the thermodynamically favored bicyclic hemiketal 21 in 92% yield as
- intermediate 22 (see Supporting Information File 1 for the details). Reasoning that the preferential coordination of the palladium catalyst with the hydroxy group at C15 and the carbonyl group at C18 in compound 22 may have deactivated the palladium catalyst [34], we protected the hydroxy group. Compound 22
- controlled by the stereoelectronic effect of the axial hydroxy group at C11 (Scheme 4) [28]. First, β-keto ester 21 was synthesized (Scheme 5). Cross-metathesis of allylic alcohol 18 and olefin 28 with the assistance of the Hoveyda–Grubbs second-generation catalyst delivered the desired product 27 in 68
Enantioselective desymmetrization strategy of prochiral 1,3-diols in natural product synthesis
Beilstein J. Org. Chem. 2025, 21, 1932–1963, doi:10.3762/bjoc.21.151
- . PPL-catalyzed desymmetrization of 10 with vinyl acetate yielded monoacetate (R)-11 in 41% yield (94% brsm) with 78% ee. Diene 12 was prepared from (R)-11 via a ten-step sequence. The following ring-closing metathesis (RCM) reaction catalyzed by Grubbs catalyst 13 converted 12 into the bicyclic
- . Alcohol 28 was obtained from 27 in two steps, and was subsequently converted to hyperione A (30) and ent-hyperione B (31) by refluxing in toluene with Shvo’s catalyst 29. Notably, the authors found that hyperione A (30) could be obtained in higher yield and enantiopurity from alcohol 28 via a two-step
- enantioselective acylation of glycerol derivatives [53]. Since then, desymmetrization strategies for prochiral 1,3-diols involving transition-metal-catalyzed acylation have been developed. Trost and co-workers then developed a Zn-based catalyst for asymmetric aldol reactions [54][55], later adapting it to the
Rhodium-catalysed connective synthesis of diverse reactive probes bearing S(VI) electrophilic warheads
Beilstein J. Org. Chem. 2025, 21, 1924–1931, doi:10.3762/bjoc.21.150
- diverse co-substrates. A high-throughput approach was used to identify promising substrate/co-substrate/catalyst combinations which were then prioritised for purification by mass-directed HPLC to yield a total of thirty reactive probes. The structural diversity of the probe set was increased by the
- multiplicity of reaction types between rhodium carbenoids and the many different co-substrate classes, and the catalyst-driven selectivity between these pathways. The probes were screened for activity against Trypanosma brucei, and four probes with promising anti-trypanosomal activity were identified
- a co-substrate (5 equiv; 16 μL of a 6.25 M solution in CH2Cl2) were added to glass vials in a 96-well reaction block, and the solvent left to evaporate after each addition. Subsequently, a dirhodium catalyst (1 mol %; 200 μL of a 1 mM solution in CH2Cl2) was also added to each vial. The final volume
Chiral phosphoric acid-catalyzed asymmetric synthesis of helically chiral, planarly chiral and inherently chiral molecules
Beilstein J. Org. Chem. 2025, 21, 1864–1889, doi:10.3762/bjoc.21.145
- framework of the diol precursors, predominantly axially chiral structures such as BINOL, H8-BINOL, SPINOL and VAPOL scaffolds, which are widely used in the development of CPA catalysts. Furthermore, the ortho-aryl substitutions of the CPA catalyst can efficiently modulate the stereochemical and electronic
- ortho-positions. The dual hydrogen-bonding interactions were critical for this reaction, ensuring that the reaction proceeded within the chiral pocket of the CPA catalyst. Moreover, the authors proposed that the extended π-substituents at the ortho-positions of CPA could engage in π–π-stacking
- interactions with the enehydrazine intermediate, which is essential for achieving high levels of stereocontrol. Using the optimal catalyst CPA 1, a series of aza[6]helicenes 3a,b was synthesized with excellent enantioselectivity and high yield. However, this method demonstrated notably reduced efficiency and
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