Search results
Search for "efficiency" in Full Text gives 1217 result(s) in Beilstein Journal of Organic Chemistry. Showing first 200.
Circumventing Mukaiyama oxidation: selective S–O bond formation via sulfenamide–alcohol coupling
Beilstein J. Org. Chem. 2026, 22, 158–166, doi:10.3762/bjoc.22.9
- slightly lower yield (88%, Table 1, entry 6). The organic base Et3N afforded 3a in 89% yield (Table 1, entry 7). These data indicate that mild inorganic bases are generally more appropriate for this transformation, with NaHCO3 offering the best combination of efficiency and practicality. Moreover
- diminished yields (68% and 88%, respectively; Table 1, entries 9 and 10). We tentatively attribute the inferior performance of NCS to its lower halogen-transfer efficiency and oxidation potential under the present conditions, which likely result in a less efficient generation of the key electrophilic sulfur
- species and in increased competitive decomposition. In contrast, the more strongly oxidizing TCCA tends to promote non-productive overoxidation pathways, thus also failing to match the efficiency of NBS. These results underscore the critical role of halogen source and oxidative strength in modulating the
Design and synthesis of an axially chiral platinum(II) complex and its CPL properties in PMMA matrix
Beilstein J. Org. Chem. 2026, 22, 143–150, doi:10.3762/bjoc.22.7
- Luminescent materials based on metal complexes have been extensively studied due to their high phosphorescence efficiency, making them promising candidates for applications in organic light-emitting diodes (OLEDs) [1][2][3][4][5], sensors [6][7][8][9], and bioimaging materials [10][11]. Among these materials
Symmetrical D–π–A–π–D indanone dyes: a new design for nonlinear optics and cyanide detection
Beilstein J. Org. Chem. 2026, 22, 131–142, doi:10.3762/bjoc.22.6
- ) efficiency [14][15][16]. Indanones are highly conjugated with a planar structure, which favors overlap between the molecules. They are building blocks for many compounds, such as organic materials for optoelectronic and NLO applications [17][18]. Research shows that the absorption wavelength of the region
Total synthesis of natural products based on hydrogenation of aromatic rings
Beilstein J. Org. Chem. 2026, 22, 88–122, doi:10.3762/bjoc.22.4
- , isoquinoline, pyridine, and related substrates can now be reduced with high efficiency and stereoselectivity, providing efficient access to saturated and partially saturated architectures vital to synthetic chemistry. Furthermore, catalytic asymmetric aromatic hydrogenation has facilitated the asymmetric total
- center and complicate catalysis. Consequently, designing cost-effective catalytic systems with enhanced efficiency, particularly for the selective hydrogenation of complex substrates, remains an essential direction for future research [33]. Hydrogenation of arenes has rapidly evolved from a specialized
- , Aggarwal and co-workers reported a concise and enantioselective synthesis of (−)-finerenone via an asymmetric hydrogen atom transfer (HAT) strategy, completing the total synthesis in just six steps with high efficiency and stereoselectivity [94]. Starting from the 2-pyridone derivative 178, the authors
Synthesis and applications of alkenyl chlorides (vinyl chlorides): a review
Beilstein J. Org. Chem. 2026, 22, 1–63, doi:10.3762/bjoc.22.1
- reported a closely related transformation building on the earlier work by Melloni (Scheme 41) [144]. The final example in their study (compound 229) illustrates that reactions involving aliphatic alkynes proceed with low efficiency and poor yields under these conditions. Notably, Mayr demonstrated that
- electronic attributes. Further improvement of the reaction was achieved by fine-tuning the Mo-metathesis catalyst (Scheme 60A–C). Schrock and Hoveyda also demonstrated that adding small amounts of HB(pin) helps remove residual water, significantly enhancing the reaction efficiency [193]. This technique can
- (Scheme 62B). Systematic optimization studies revealed that additives, such as magnesium bromide etherate or HMPA, had a pronounced impact on both reaction efficiency and stereoselectivity. In 2005, Yan reported that the direct oxidative addition of chloroform to a Mg–TiCl4 bimetallic system generates a
One-pot synthesis of ethylmaltol from maltol
Beilstein J. Org. Chem. 2025, 21, 2755–2760, doi:10.3762/bjoc.21.212
- substrate for methylation, affording O-methyl ethylmaltol (9c) in moderate yield (45%, Table 2, entry 3). Subsequent O-demethylation of 9c to ethylmaltol (1) was achieved with boron tribromide in dichloromethane in 65% yield. While an O-methyl group proved successful, the unsatisfactory overall efficiency
Sustainable electrochemical synthesis of aliphatic nitro-NNO-azoxy compounds employing ammonium dinitramide and their in vitro evaluation as potential nitric oxide donors and fungicides
Beilstein J. Org. Chem. 2025, 21, 2739–2754, doi:10.3762/bjoc.21.211
- overcome existing constraints in functional group compatibility, efficiency, and reagent scope. In this regard, the direct formation of nitrogen-nitrogen or nitrogen-oxygen bonds presents a significant challenge due to the variety of possible side processes and the low thermodynamic driving force for N–N
Recent advancements in the synthesis of Veratrum alkaloids
Beilstein J. Org. Chem. 2025, 21, 2657–2693, doi:10.3762/bjoc.21.206
- will not be shown separately. For an example for this color coding, the (−)-englerin A (11) synthesis of the Christmann group is displayed in Scheme 3, together with the symbol explanation mentioned above [12]. This visual aid helps identifying the convergency and efficiency of synthetic routes, as
Chemoenzymatic synthesis of the cardenolide rhodexin A and its aglycone sarmentogenin
Beilstein J. Org. Chem. 2025, 21, 2637–2644, doi:10.3762/bjoc.21.204
- overall synthetic efficiency of this route. Therefore, the development of more efficient syntheses of rhodexin A is of great significance. Recently, chemoenzymatic syntheses of steroids have made excellent progress, which can enormously shorten the synthetic routes and increase the overall efficiency [23
- -reduction of the butenolide motif. The low efficiency of this reaction prompted us to pursue an alternative two-step approach. First, we performed the deprotection to remove all the Bz groups of 16 by NH3/MeOH, furnishing the saccharide 17 in 95% yield. Eventually, the quick stereospecific C11 carbonyl
Thiazolidinones: novel insights from microwave synthesis, computational studies, and potentially bioactive hybrids
Beilstein J. Org. Chem. 2025, 21, 2618–2636, doi:10.3762/bjoc.21.203
- [52], acetic acid [53], or solvent-free processes [54]. Ionic liquids, such as [Bu4N][OH] [55], [bmim][OH] [56], and [Et3NH][HSO4] [57], and deep eutectic solvents (DES) [58] have been introduced to improve efficiency. Traditional methods for synthesizing these compounds, however, face several
Efficient solid-phase synthesis and structural characterization of segetalins A–H, J and K
Beilstein J. Org. Chem. 2025, 21, 2612–2617, doi:10.3762/bjoc.21.202
- from the high cost of the specialized resin and large solvent volumes required for dilution, coupled with DPPA's poor efficiency in forming sterically hindered peptide bonds involving residues like Val or Ile. Dahiya and Kaur synthesized segetalin C (3) via a solution-phase fragment coupling strategy
- and solid-phase approaches are viable for peptide synthesis, Fmoc-based SPPS offers distinct advantages in operational simplicity and efficiency for laboratory-scale production [20]. We therefore devised a streamlined solid-phase strategy for synthesizing the Vaccaria segetalis cyclopeptide family
- sequences, coupling efficiency was significantly enhanced using a 1:1 mixture of 1-hydroxybenzotriazole (HOBt) and 2-(1H-benzotriazol-1-yl)-1,1,3,3-tetramethyluronium hexafluorophosphate (HBTU) in DMF [23]. Finally, we obtained crude linear peptides with 75% to 95% yields (Table 1). The critical head-to
Silica gel with covalently attached bambusuril macrocycle for dicyanoaurate sorption from water
Beilstein J. Org. Chem. 2025, 21, 2604–2611, doi:10.3762/bjoc.21.201
- . Next, we evaluated the efficiency of the SG-NHCO-BU1 material in sorbing dicyanoaurate. First, we showed that SG-BU1 is stable under the experimental conditions (Supporting Information File 1, Figure S5C) and next, we investigated both materials for dicyanoaurate sorption. Thus, we gradually increased
- , exhibiting near-quantitative binding at millimolar concentrations [17]. The lower binding efficiency of BUs attached to the material compared to the free macrocycle in solution can likely be attributed to the heterogeneous nature of the solid-phase system. Moreover, the anion binding ability of BU1 may be
- [17]. The finding is also in agreement with our reported results on the noncovalent SG-BnBU system, which showed significantly higher sorption efficiency towards dicyanoaurate over dicyanoargentate [14]. We next examined the recyclability of the materials. Only SG-NHCO-BU1 was used in these
Visible-light-driven NHC and organophotoredox dual catalysis for the synthesis of carbonyl compounds
Beilstein J. Org. Chem. 2025, 21, 2584–2603, doi:10.3762/bjoc.21.200
- and the acylazolium complex B (Ep = −0.81 V vs SCE), single-electron transfer (SET) reduction of B was thermodynamically feasible; however, the efficiency was found to be significantly low. The oxidation potential was measured to be around [Ep = +0.72 V] vs SCE, indicating that it is sufficiently
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
- enhance synthetic efficiency, reduce costs, and provide robust solutions to challenges encountered in the synthesis of complex molecular architectures. Ryania diterpenes are natural products characterized by intricate structures and high oxidation states. Biological studies have revealed that the family
- employed therein while providing an in-depth analysis of the innovation of classical methods, the application of emerging technologies, and the enhancements in synthetic efficiency achieved through multi-strategy integration. The aim is to offer readers a clear understanding of the developmental trajectory
- the simultaneous construction of four quaternary carbon centers (C1, C4, C5, and C12) and the core AB bicyclic skeleton, markedly improving synthetic efficiency. Subsequent oxidative desymmetrization of the C14–C15 olefin in (±)-33 established the sterically hindered C11 quaternary carbon center. An α
Pentacyclic aromatic heterocycles from Pd-catalyzed annulation of 1,5-diaryl-1,2,3-triazoles
Beilstein J. Org. Chem. 2025, 21, 2524–2534, doi:10.3762/bjoc.21.194
- ring itself to also include benzophenanthridine, dibenzonaphthyridine, and benzophenanthroline heterocycles of previously unreported identity (Figure 2). In addition to studying how naphthalene, quinolone, and isoquinoline incorporation impact click and annulation efficiency, characterizing the
- isoquinoline subunits. Heterocycle subunit identity and triazole C/N connectivity influenced the annulation reaction efficiency. Aromatic π-system expansion resulting from annulation was characterized by NMR, absorption and emission spectroscopy. Five benzotriazolophenanthroline regioisomers sharing structural
Effect of a photoswitchable rotaxane on membrane permeabilization across lipid compositions
Beilstein J. Org. Chem. 2025, 21, 2498–2512, doi:10.3762/bjoc.21.192
- bilayers through the shuttling of the macrocycle carrying the ions or through a relay mechanism [10][11]. In one example, the isomerization of an azobenzene photoswitch incorporated into the axle was used to modulate the shuttling rate of the macrocycle and, consequently, the efficiency of potassium ion
Assembly strategy for thieno[3,2-b]thiophenes via a disulfide intermediate derived from 3-nitrothiophene-2,5-dicarboxylate
Beilstein J. Org. Chem. 2025, 21, 2489–2497, doi:10.3762/bjoc.21.191
- cleavage of the S–S bond and the subsequent S-alkylation reaction were successful. To suppress the side reaction and improve reduction efficiency, we next employed DMF as a polar aprotic solvent. In Table 2, entry 4, reduction of disulfide 3 in DMF at 75 °C with NaBH4 was complete within 15 min. The excess
Palladium-catalyzed regioselective C1-selective nitration of carbazoles
Beilstein J. Org. Chem. 2025, 21, 2479–2488, doi:10.3762/bjoc.21.190
- were ineffective in improving the reaction outcome (Table 1, entry 6). Other palladium complexes promoted the formation of 2a but with diminished efficiency (Table 1, entries 7 and 8). Varying the amount of AgNO3 did also not lead to a better yield (Table 1, entry 9), and alternative nitro sources also
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
- University, Liaoning Shenyang 110016, China 10.3762/bjoc.21.189 Abstract Natural products with topologically complex architectures are important sources in drug discovery. The pursuit of conciseness and efficiency in the total synthesis of natural products promotes continuous innovation and the development
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
- . Irritation of a solution of 124 in CH3OH using a medium-pressure Hg lamp resulted in the formation of methyl ester 125 as a single diastereomer with a yield of 30%. Due to the decrease in the efficiency of this reaction at higher loads (>50 mg), the thermal conditions for the Wolff rearrangement were tested
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
- all of the above criteria. For example, it can be synthesized easily and with high efficiency through the biodiesel production process, it can be reused, it is stable under storage conditions, it can be obtained from renewable resources, it is biodegradable, non-flammable etc. It is widely
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
- desired reaction [17]. Under these conditions, the reaction was performed on a 5 mmol scale without any loss of efficiency. We next evaluated the scope of the developed protocol. The electronic and steric nature of substituents had a minimal impact on the product yields and in most cases, the desired
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
- fluorescence quenching efficiency upon iodide binding compared to the rigid WDG (KPBG/KWDG = 22.78), demonstrating its potential as a highly sensitive optical probe and offering a novel strategy for engineering dynamic supramolecular receptors. Two carbazole-based macrocyclic probes, PBG (flexible benzene ring
- cavity, which may not perfectly complement iodide's size or geometry, leading to weaker interactions and a higher-energy (less stable) complex. This energy difference aligns with the observed higher binding constant (K) of PBG, demonstrating that structural flexibility enhances anion-binding efficiency
Adaptive experimentation and optimization in organic chemistry
Beilstein J. Org. Chem. 2025, 21, 2367–2368, doi:10.3762/bjoc.21.180
- analyze experiments using machine learning optimization algorithms [5][6]. Together, these capabilities are dramatically increasing the speed and efficiency of chemical optimization with respect to economic and environmental objectives [7]. The contributions in this thematic issue showcase innovative
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
- 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
- -stilbenes have 5-membered rings fused to the carbon–carbon double bond, are more photostable, and undergo reversible photoisomerization with higher efficiency (Figure 2) [75]. Notably, their cis isomer exhibits higher thermal stability than that of other commonly used photoswitches, such as azobenzene. This
- dithienylethene is in the closed form, caused by photoinduced electron transfer (PET) from the fluorescent pyrene stopper to the acceptor dithienylethene (Figure 15). Moreover, the efficiency of the PET is modulated by the macrocycle shuttling motion between the two recognition sites due to differences in
Other Beilstein-Institut Open Science Activities
