Formaldehyde surrogates in multicomponent reactions

• Cecilia I. Attorresi,
• Javier A. Ramírez and
• Bernhard Westermann

Beilstein J. Org. Chem. 2025, 21, 564–595, doi:10.3762/bjoc.21.45

• first reacts with the aniline under cobalt(III) catalysis, and the resulting intermediate C then attacks the thionium ion A. Quinolines of general structure II are formed after the loss of methyl sulfide from intermediate D, followed by final cyclization of intermediate E (Scheme 8, path II

• various substitution patterns in the aromatic ring, allowing a high variety of quinolines of general structure I and II. In a related work, quinolines of structure I (Scheme 8) could be obtained by similar reaction pathways. Jadhav et al. proposed a three-component cascade reaction between anilines

• was carried out via copper catalysis or iodine–acid catalysis. Interestingly, when aliphatic amines are employed (R3 = n-Pr, n-Bu, product 8) only the N atoms are incorporated in the structure of the final product, probably because the high temperature favors the elimination of the alkyl group. The

Study of the interaction of 2H-furo[3,2-b]pyran-2-ones with nitrogen-containing nucleophiles

• Constantine V. Milyutin,
• Andrey N. Komogortsev and
• Boris V. Lichitsky

Beilstein J. Org. Chem. 2025, 21, 556–563, doi:10.3762/bjoc.21.44

• structure of used N-nucleophile various types of a heterocyclic system can be obtained. A large number of examples of reactions with substituted amines have been reported in the literature. Generally, this process includes opening of the furanone ring followed by cyclization to the pyrrolone moiety [6][7][8

• recyclization can be extended for the synthesis of relative isoxazolone 11. In this case the reaction of furanone 1c with hydroxylamine hydrochloride 12 also was carried out in refluxing EtOH for 8 h (Scheme 7). All prepared products 8, 10 and 11 are solid crystalline compounds whose structure was proved by 1H

• units was isolated (Scheme 9). The structure of synthesized compound 13 was unambiguously confirmed by X-ray diffraction. Conclusion In summary, we studied the interaction of 2H-furo[3,2-b]pyran-2-one derivatives with various amines and hydrazines. It was demonstrated that, depending on the nature of

Vinylogous functionalization of 4-alkylidene-5-aminopyrazoles with methyl trifluoropyruvates

• Judit Hostalet-Romero,
• Laura Carceller-Ferrer,
• Gonzalo Blay,
• Amparo Sanz-Marco,
• José R. Pedro and
• Carlos Vila

Beilstein J. Org. Chem. 2025, 21, 533–540, doi:10.3762/bjoc.21.41

• 3aa–ca in good yields (47–69%). On the other hand, the reaction with tetrahydro-4H-pyran-4-one (1d) occurred with a significant decrease in yield, dropping to 11%. The yield is also affected by the number of carbon atoms of the starting cyclic ketone 1. In the case of structure 3ea, which involves 2

• chromatography. Diastereoisomeric ratio (dr) determined by 1H NMR of the crude reaction mixture. Plausible mechanism and X-ray structure of compound 5aca. Optimization of the reaction conditions.a Supporting Information Supporting Information File 14: Detailed experimental procedures, characterization data, and

Cryptophycin unit B analogues

• Thomas Schachtsiek,
• Jona Voss,
• Maren Hamsen,
• Beate Neumann,
• Hans-Georg Stammler and
• Norbert Sewald

Beilstein J. Org. Chem. 2025, 21, 526–532, doi:10.3762/bjoc.21.40

• connected to the homing device by a linker. For covalent attachment of the drug to the linker a suitable functional group is needed such as an amino, hydroxy, carboxy or sulfhydryl group [7]. Since the cryptophycins’ discovery, considerable efforts were made for the establishment of structure–activity

• of, firstly, m-chloro-p-(methylamino) derivative 1 to dissect the structure–activity relationship between the primary (IC50(CCRF-CEM) = 0.58 nM), secondary, and tertiary amine (IC50(CCRF-CEM) = 54 pM) derivatives [20]. Secondly, p-(dimethylamino) derivative 2 was synthesised to investigate the effect

• control of equivalents and pH, or Leuckart–Wallach-like reaction with ammonium formate and Pd/C [25] provided monomethylaniline 7 in 37% and 35% yield, respectively. The absolute structure of monomethylaniline 7 was confirmed by single-crystal X-ray diffraction measurements (Figure 2). Compound 7

Deep-blue emitting 9,10-bis(perfluorobenzyl)anthracene

• Long K. San,
• Sebastian Balser,
• Brian J. Reeves,
• Tyler T. Clikeman,
• Yu-Sheng Chen,
• Steven H. Strauss and
• Olga V. Boltalina

Beilstein J. Org. Chem. 2025, 21, 515–525, doi:10.3762/bjoc.21.39

• photochemical reaction. Its structure was elucidated by NMR spectroscopy and single crystal X-ray diffractometry. The latter revealed no π–π interaction between neighboring ANTH cores. A combination of high photoluminescence quantum yield (PLQY) of 0.85 for 9,10-ANTH(BnF)2, its significantly improved

• ratio was found to be 1.74 (theoretical = 1.75), confirming the composition to be ANTH(BnF)2. Slow evaporation of a CH2Cl2 solution of 9,10-ANTH(BnF)2 at 2 °C afforded off-white plates suitable for X-ray diffraction. The structure shown in Figure 2 (top panel) confirmed the 9,10-substitution pattern

• , whereas 9,10-ANTH(BnF)2 loses vibronic structure in the emission spectrum. This may be the result of different conformations upon relaxation [31]. The HOMO–LUMO gap (Eg) decreases from ANTH (3.28 eV) to 9,10-ANTH(BnF)2 (3.05 eV). A decrease in Eg is regarded as one of the methods for improving the

Unprecedented visible light-initiated topochemical [2 + 2] cycloaddition in a functionalized bimane dye

• Metodej Dvoracek,
• Brendan Twamley,
• Mathias O. Senge and
• Mikhail A. Filatov

Beilstein J. Org. Chem. 2025, 21, 500–509, doi:10.3762/bjoc.21.37

• E. M. Kosower in 1978. In this study, we report the topochemical cycloaddition of diethyl 2,6-dichloro-1,7-dioxo-1H,7H-pyrazolo[1,2-a]pyrazole-3,5-dicarboxylate (Cl2B), initiated by visible light. Crystal structure analysis confirmed that the reactive double bonds are parallel and coplanar, in line

• compounds used thus far is likely due to reliance on their ability to undergo π-stacking interactions, which facilitate face-to-face packing. Therefore, the discovery of a new type of structure capable of undergoing this reaction, as reported here, represents a significant advancement, enabling the

• development of a novel scaffold for topochemically active monomers. Bimanes Bimanes, a class of bicyclic compounds first synthesized by Kosower and Pazhenchevsky in 1978 [16], are based on a 1H,7H-pyrazolo[1,2-a]pyrazole-1,7-dione scaffold. The general structure of a bimane is depicted in Figure 1a. The term

Synthesis of N-acetyl diazocine derivatives via cross-coupling reaction

• Thomas Brandt,
• Pascal Lentes,
• Jeremy Rudtke,
• Michael Hösgen,
• Christian Näther and
• Rainer Herges

Beilstein J. Org. Chem. 2025, 21, 490–499, doi:10.3762/bjoc.21.36

• azobenzenes, spiropyranes and diarylethenes in organic solvents [3][13][15]. There are two strategies of applying diazocines in photopharmacology. The first one exploits the structural similarity of the tricyclic diazocine framework to the tricyclic structure of, e.g., tetrahydrodibenzazocines [16][17] and

• because the design of a photoswitchable agent usually starts with a known, non-switchable drug or a known biological molecule, which is already carefully "optimized" either by pharmaceutical industry or by nature. Hence, there is a high risk that any change in structure will also lead to a reduction in

• substitution. Substituents such as halogen atoms must be introduced into the N-acetyl diazocine structure during the synthesis of the building blocks. In the present work we start from mono- and dihalogenated N-acetyl diazocine 2–4 (Figure 2) and focus on the further derivatization via cross-coupling reactions

Electrochemical synthesis of cyclic biaryl λ³-bromanes from 2,2’-dibromobiphenyls

• Andrejs Savkins and
• Igors Sokolovs

Beilstein J. Org. Chem. 2025, 21, 451–457, doi:10.3762/bjoc.21.32

• extractive workup followed by reversed-phase chromatography and its structure was unambiguously confirmed by X-ray crystallography (Table 1, graphic). Gratifyingly, a two-fold increase in the yield was achieved by a slight reduction of the current density to j = 8 mA·cm−2 (entry 2 vs entry 1 in Table 1). A

• : Representative jp vs v0.5 slope values for oxidation of Martin’s bromane precursor 6 (ref. [17]). D: Plausible reaction mechanism. Optimization of electrochemical oxidation/cyclization conditions.a Supporting Information Crystallographic data for the structure reported in this paper have been deposited with the

Beyond symmetric self-assembly and effective molarity: unlocking functional enzyme mimics with robust organic cages

• Keith G. Andrews

Beilstein J. Org. Chem. 2025, 21, 421–443, doi:10.3762/bjoc.21.30

• exploiting emergent geometric rules and post-assembly modifications; (3) improved screening and collection of detailed structure–activity-relationship (SAR) data for modular systems to allow systematic design, rational and computational development, and identification of novel activity. These developments

• constriction (ground-state destabilization) are also possible [140][168][169][170]. The metals can sometimes participate in redox catalysis [171], and may be stabilized by the cage structure [160][172][173][174]. The organic part of the MOC has also been levied as a hydrogen-bond donor to activate an

• chemistry [200]. “Switchable” metal-organic cages [212] use a stimulus like light to change ligand geometries. This often triggers disassembly since new geometries can lead to new thermodynamic minima, though where geometric changes are tolerated within the original structure the stimuli can trigger guest

Unraveling aromaticity: the dual worlds of pyrazole, pyrazoline, and 3D carborane

• Zahra Noori,
• Miquel Solà,
• Clara Viñas,
• Francesc Teixidor and
• Jordi Poater

Beilstein J. Org. Chem. 2025, 21, 412–420, doi:10.3762/bjoc.21.29

• compared to the C–C bond by 2.4 kcal/mol further supports the above statement [44]. Next, we have compared the above o-carborane-fused pyrazoles with a series of reference systems with the aim to better understand the electronic structure of the fused heterocycle and its aromaticity (Figure 3). First, the

The effect of neighbouring group participation and possible long range remote group participation in O-glycosylation

• Rituparna Das and
• Balaram Mukhopadhyay

Beilstein J. Org. Chem. 2025, 21, 369–406, doi:10.3762/bjoc.21.27

• characterisation of the isolated samples significantly arduous and faulty. Therefore, the syntheses of these important carbohydrates through chemical means became inevitable to elucidate the structure unambiguously and to get hold of their biological implications with minimal doubt [17]. The oligosaccharide

Synthesis, structure, ionochromic and cytotoxic properties of new 2-(indolin-2-yl)-1,3-tropolones

• Yurii A. Sayapin,
• Eugeny A. Gusakov,
• Inna O. Tupaeva,
• Alexander D. Dubonosov,
• Igor V. Dorogan,
• Valery V. Tkachev,
• Anna S. Goncharova,
• Gennady V. Shilov,
• Natalia S. Kuznetsova,
• Svetlana Y. Filippova,
• Tatyana A. Krasnikova,
• Yanis A. Boumber,
• Alexey Y. Maksimov,
• Sergey M. Aldoshin and
• Vladimir I. Minkin

Beilstein J. Org. Chem. 2025, 21, 358–368, doi:10.3762/bjoc.21.26

• determined. The structure of 2-(3,3-dimethyl-3H-benzo[g]indolin-2-yl)-5,6,7-trichloro-1,3-tropolone was determined by X-ray diffraction analysis. The compounds obtained are capable of switching emission at 420–440 nm and 476–530 nm upon successive exposure to CN− and Hg2+ ions in an acetonitrile solution. 2

• ; Introduction 1,2-Benzoquinones represent unique building blocks for various classes of heterocyclic systems. Their structure depends on the reactivity of the initial heterocycles and 1,2-benzoquinones, as well as on the reaction conditions. In the series of 2-methylquinolines [1], 2-methylquinoxalines [2], 2

• reaction of o-chloranil with benzoannelated derivatives of 2,3,3-trimethylindolenine, a comprehensive evaluation of the structure of the compounds obtained using quantum chemical methods, X-ray diffraction analysis, two-dimensional correlation NMR spectroscopy, as well as investigation of their ionochromic

Synthesis, characterization, antimicrobial, cytotoxic and carbonic anhydrase inhibition activities of multifunctional pyrazolo-1,2-benzothiazine acetamides

• Ayesha Saeed,
• Shahana Ehsan,
• Muhammad Zia-ur-Rehman,
• Erin M. Marshall,
• Sandra Loesgen,
• Abdus Saleem,
• Simone Giovannuzzi and
• Claudiu T. Supuran

Beilstein J. Org. Chem. 2025, 21, 348–357, doi:10.3762/bjoc.21.25

• oxygen atom [50]. Preferential N-alkylation (over O-alkylation) of 1,2-benzothiazine scaffolds has also been carried out by Ahmad and co-workers in 2014 and Szczęśniak-Sięga and companions in 2018 [37][51]. Structure elucidation of all the synthesized derivatives was carried out using 1H, 13C NMR, and

Synthesis of new condensed naphthoquinone, pyran and pyrimidine furancarboxylates

• Kirill A. Gomonov,
• Vasilii V. Pelipko,
• Igor A. Litvinov,
• Ilya A. Pilipenko,
• Anna M. Stepanova,
• Nikolai A. Lapatin,
• Ruslan I. Baichurin and
• Sergei V. Makarenko

Beilstein J. Org. Chem. 2025, 21, 340–347, doi:10.3762/bjoc.21.24

• data, they luminesce in DMSO solution when irradiated with light at wavelengths of 352 and 283 nm. Compounds 7a–f are capable of existing as lactim–lactam tautomers due to the presence of an amide fragment in their structure (Scheme 7). At the same time, the 1H and 13C NMR spectra of compounds 7a–f

• phase and visualized under UV light (λ 254 nm). X-ray structure determination X-ray diffraction studies of single crystals of compounds 5a, 5b, 6b, 6c, and 7a were carried out on a Bruker D8 QUEST diffractometer. The cell parameters and experimental data were obtained at 100 K (graphite monochromator

• , λMo Kα = 0.71073 Å, ω and φ scanning in 0.5° steps) at the distributed spectral-analytical center of shared facilities for study of structure, composition and properties of substances and materials of FRC Kazan scientific center of Russian academy of sciences. Crystals of compounds suitable for X-ray

Antibiofilm and cytotoxic metabolites from the entomopathogenic fungus Samsoniella aurantia

• Rita Toshe,
• Syeda J. Khalid,
• Blondelle Matio Kemkuignou,
• Esteban Charria-Girón,
• Paul Eckhardt,
• Birthe Sandargo,
• Kunlapat Nuchthien,
• J. Jennifer Luangsa-ard,
• Till Opatz,
• Hedda Schrey,
• Sherif S. Ebada and
• Marc Stadler

Beilstein J. Org. Chem. 2025, 21, 327–339, doi:10.3762/bjoc.21.23

• [6], which has to the best of our knowledge not been studied before on its secondary metabolism. The current study deals with the isolation and characterization of the major bioactive principles of the ex-holotype strain of Samsoniella aurantia. Results and Discussion Structure elucidation Compound 1

• ]+ (calculated 446.1962). The UV–vis spectrum of 1 (Figure S3, Supporting Information File 1) revealed a prominent absorption peak (λmax) at 434 nm in the visible region reflected by being yellow-colored and suggesting the presence of an extended conjugated π-system in its structure. The 1H NMR and 1H–1H COSY

• fungus Beauveria bassiana [11]. Further confirmation of the depicted structure of 1 was obtained via its HMBC spectrum (Figure 2, Figure S8, Supporting Information File 1) that revealed key correlations from the two aromatic protons H-5'/H-9' to the C-3' and in turn a key correlation for H-3' to the

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

• unsaturated ring structure derived from squaric acid [47], has attracted attention due to its ability to promote single-electron transfer [48]. These compounds exhibit significant NIR fluorescence, making them valuable in applications such as biomolecule probing. Additionally, squaraine derivatives are well

• superoxide (O2•−) are simultaneously produced by the same photocatalytic system. In order to favor their combination leading to the peroxynitrite anion (ONOO−), the NO-releasing structure is incorporated in a polymeric structure 66 which generates micellar nanoparticles. The substituent R’ in the

Molecular diversity of the reactions of MBH carbonates of isatins and various nucleophiles

• Zi-Ying Xiao,
• Jing Sun and
• Chao-Guo Yan

Beilstein J. Org. Chem. 2025, 21, 286–295, doi:10.3762/bjoc.21.21

• yields. The single crystal structure of the compound 6e was determined by X-ray diffraction (Figure 3). The similar reaction of more nucleophilic tri(tert-butyl)phosphine and MBH carbonate of isatin resulted in a mixture of products. After carefully screening the reaction conditions, we found that DABCO

• also led to the development of a synthetic protocol for the convenient synthesis of 30 diversely substituted oxindole derivatives. Single crystal structure of compound 5a. Single crystal structure of compound 5j. Single crystal structure of compound 6e. Single crystal structure of compound 7a. Single

• crystal structure of compound 8a. Reaction of arylamines and MBH carbonates of isatins. Reaction conditions: MBH carbonate of isatin (0.1 mmol), aromatic amine (0.1 mmol), DMAP (0.02 mmol, 20 mol %), toluene (5.0 mL), rt, 1 h; yields refer to isolated yields. Reaction of arylamines and MBH maleimides of

Oxidation of [3]naphthylenes to cations and dications converts local paratropicity into global diatropicity

• Abel Cárdenas,
• Zexin Jin,
• Yong Ni,
• Jishan Wu,
• Yan Xia,
• Francisco Javier Ramírez and
• Juan Casado

Beilstein J. Org. Chem. 2025, 21, 277–285, doi:10.3762/bjoc.21.20

• systems in which charge defects are responsible for conductivity in their corresponding conducting polymers. Acenes are the archetypal structure of small polycyclic aromatic hydrocarbons with a π-electron structure expanded over a sequence of linearly fused benzenes [4]. Whereas acenes, up to substituted

• is using energetic parameters unequivocally associated to individual bonds. This is the case of the vibrational force constants [22]. They are defined as the second derivative of the molecular energy, in the minimum energy molecular structure, with respect to the nuclear displacement coordinates

• perimeter, whereas up to three independent ring currents are expected for the m-22+ structure. To visualize these results, we have analyzed the ACID plots for the neutral and cationic species of m-1 and m-2 [20][26]. Figure 8 shows these plots for the dications, while those of the neutral and radical cation

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

• consisting of four molecules, every two of them are stacked with the plane-to-plane distance of 3.45 Å (Figure 1c), displaying a lamellar π–π stacking motif in the overall packing structure (Figure S1 in Supporting Information File 1) [26][27][28][29]. The X-ray structure is well consistent with a model

• micrometers, as demonstrated by SEM. These results provide not only an easy access to highly emissive BPP derivatives with potential as organic fluorescent materials, but also an insight to design derivatives of other PAHs with enhanced fluorescence and charge transfer character. Single crystal structure of

Effect of substitution position of aryl groups on the thermal back reactivity of aza-diarylethene photoswitches and prediction by density functional theory

• Misato Suganuma,
• Daichi Kitagawa,
• Shota Hamatani and
• Seiya Kobatake

Beilstein J. Org. Chem. 2025, 21, 242–252, doi:10.3762/bjoc.21.16

• and frequency calculations of closed-ring isomers (closed) and transition states (TS) were carried out using Gaussian 16 Rev. C.01 program package. The TS structure was optimized using Opt = TS keyword with Berny algorithm. To obey unrestricted Kohn–Sham solution, the broken-symmetry guess was

Visible-light-promoted radical cyclisation of unactivated alkenes in benzimidazoles: synthesis of difluoromethyl- and aryldifluoromethyl-substituted polycyclic imidazoles

• Yujun Pang,
• Jinglan Yan,
• Nawaf Al-Maharik,
• Qian Zhang,
• Zeguo Fang and
• Dong Li

Beilstein J. Org. Chem. 2025, 21, 234–241, doi:10.3762/bjoc.21.15

• properties that can modify the activity and pharmacokinetic profiles of drugs [7]. Prominent examples include pantoprazole, a widely used proton-pump inhibitor (PPI) featuring a CF2H group; deracoxib, another drug that also incorporates a CF2H moiety in its structure; and a MET inhibitor specifically

Streamlined modular synthesis of saframycin substructure via copper-catalyzed three-component assembly and gold-promoted 6-endo cyclization

• Asahi Kanno,
• Ryo Tanifuji,
• Satoshi Yoshida,
• Sota Sato,
• Saori Maki-Yonekura,
• Kiyofumi Takaba,
• Jungmin Kang,
• Kensuke Tono,
• Koji Yonekura and
• Hiroki Oguri

Beilstein J. Org. Chem. 2025, 21, 226–233, doi:10.3762/bjoc.21.14

• structure of 16 was confirmed by serial X-ray crystallography using an X-ray free-electron laser (XFEL) [deposition number CCDC 2352718) [54][55]. We then performed a Strecker-type reaction on the aldehyde 16 to construct an α-aminonitrile 17. To our delight, the key intermediate, 2,3-diaminobenzofuran 11

• a fluorescent intermediate 18, and subsequent ring opening allowed a streamlined one-pot access to the substructure of THIQ alkaloids 14 in a good yield of 60% from 11. The structure of the resulting 14 was elucidated through comprehensive two-dimensional NMR spectroscopy, complemented by NOE

• Strecker reaction and cyclization to form the 2,3-diaminobenzofuran moiety, and gold(I)-promoted cascade sequence via 6-endo hydroamination, spontaneous dehydrogenative oxidation followed by ring opening. Carbon numbering was assigned in accordance with natural products. The structure of 16 was determined

Heteroannulations of cyanoacetamide-based MCR scaffolds utilizing formamide

• Marios Zingiridis,
• Danae Papachristodoulou,
• Despoina Menegaki,
• Konstantinos G. Froudas and
• Constantinos G. Neochoritis

Beilstein J. Org. Chem. 2025, 21, 217–225, doi:10.3762/bjoc.21.13

• structure was obtained, revealing certain geometrical features. Keywords: 2-amino-substituted heterocycles; cyanoacetamide; Gewald reaction; multicomponent reaction (MCR); pyrimidine; Introduction The term “net-zero carbon” is becoming increasingly common as we consider a future marked by a rising global

• was observed at an average wavelength of 384 nm for 5a–e, 439 nm for 6a–e and 430 nm for 7a–e (see Supporting Information File 1 for detailed information). In support of the proposed scaffold 7b, we were able to solve its crystal structure (Figure 3). An intermolecular bifurcated hydrogen bond network

• pyrimidine scaffold. Representative fluorescence spectrum of compounds 5b (λex = 330 nm) and 6e (λex = 430 nm) at 0.2 M in DMSO. Molecular geometry observed within the crystal structure of compound 7b (CCDC 2376493). Strategies towards targeted adducts: A) Niementowski quinazoline synthesis utilizing

Hydrogen-bonded macrocycle-mediated dimerization for orthogonal supramolecular polymerization

• Wentao Yu,
• Zhiyao Yang,
• Chengkan Yu,
• Xiaowei Li and
• Lihua Yuan

Beilstein J. Org. Chem. 2025, 21, 179–188, doi:10.3762/bjoc.21.10

• of noncovalent interactions that work independently from each other [5][6][7][8]. Generating such motifs with orthogonal propensity is appealing not only for the construction of supramolecular polymers with the ability to modulate their structure and properties in multiple ways through adjustment of

• , particularly π-stacking interactions between the aromatic rings in a parallel fashion from both host and guest, which is demonstrated by the crystal structure of the key element of the recognition motif. Results and Discussion Backdrop for design considerations Our interest in macrocycle-mediated

• structure would also be found in the solid state. Fortunately, single crystals of the complex H1 ⊃ G1 were obtained by slow evaporation of chloroform/acetone solvent (1:1, v/v) into a small amount of methanol over the course of two weeks. Indeed, analysis of the crystal structure of the complex revealed a

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

• copper-coordinated azomethine ylide 39. Subsequently, the chiral products 35–37 are produced through the reaction between the metalated azomethine ylide 39 and the quinone intermediate 38. The reaction pathway, either 1,4-addition or 1,6-addition, depends on the structure of the hydroquinone 34. The less

• of analogous substrates demonstrates that a bidentate nitrogen structure and a free N–H group are essential for this transformation. The catalytic cycle begins with the coordination of 8-aminoquinoline 71 to Cu(II) catalyst 74, providing an arylcopper complex 76 (Figure 13). This is followed by a