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Search for "B" in Full Text gives 3144 result(s) in Beilstein Journal of Organic Chemistry. Showing first 200.

Microwave-enhanced additive-free C–H amination of benzoxazoles catalysed by supported copper

  • Andrei Paraschiv,
  • Valentina Maruzzo,
  • Filippo Pettazzi,
  • Stefano Magliocco,
  • Paolo Inaudi,
  • Daria Brambilla,
  • Gloria Berlier,
  • Giancarlo Cravotto and
  • Katia Martina

Beilstein J. Org. Chem. 2025, 21, 1462–1476, doi:10.3762/bjoc.21.108

Graphical Abstract
  • changes in the position and shape of the νNH2 and δNH2 bands are observed, which are an indirect indication of the interaction of the amino group with the metal (curve b) [51]. On the other hand, major changes are observed in the spectrum of 5 wt % Si –MonoAm-Cu(II) (curve d). These are particularly
  • comparing the corresponding FESEM images of the fresh and used catalyst (see Figure 7a and b). EDS maps show a homogeneous dispersion of copper on the catalyst with this dispersion being maintained after the catalysts is used (panels a and b of Figure 8). Conclusion The study demonstrates that the efficient
  • the reaction started, the reactor was pressurized with 5 bar of air (for experimental MW setup see Supporting Information File 1). Reaction of benzimidazole with piperidine. a) Reaction scheme including intermaidates and b) conversion and selectivity plot of the C2-amination of benzoxazole with
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Published 15 Jul 2025

Wittig reaction of cyclobisbiphenylenecarbonyl

  • Taito Moribe,
  • Junichiro Hirano,
  • Hideaki Takano,
  • Hiroshi Shinokubo and
  • Norihito Fukui

Beilstein J. Org. Chem. 2025, 21, 1454–1461, doi:10.3762/bjoc.21.107

Graphical Abstract
  • stable figure-eight conformation A to a metastable bathtub conformation B with a small energy difference of approximately 2 kcal mol–1 [21]. In this paper, we discuss the effect of the transformation of the carbonyl groups on the conformational change of the figure-eight structure. We thus intentionally
  • . The racemization dynamics of 5 was investigated by DFT calculations at the B3LYP/6-31G(d) level of theory, employing the Gaussian 16 software package and the global reaction route mapping (GRRM17) [23] program (Figure 4). The interconversion between figure-eight conformation (M,M)-B and bathtub
  • conformation (Sa,Sa)-A is feasible with a small activation barrier of 9.9 kcal mol−1. The figure-eight conformer (M,M)-B untwists to adopt an achiral conformation C with the exo-alkene units rotated inwards in opposite directions. These conformational changes are almost identical to those of CBBC 1. However
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Published 14 Jul 2025

Advances in nitrogen-containing helicenes: synthesis, chiroptical properties, and optoelectronic applications

  • Meng Qiu,
  • Jing Du,
  • Nai-Te Yao,
  • Xin-Yue Wang and
  • Han-Yuan Gong

Beilstein J. Org. Chem. 2025, 21, 1422–1453, doi:10.3762/bjoc.21.106

Graphical Abstract
  • helical architectures, have attracted considerable attention due to their intrinsic chirality and tunable optoelectronic properties. Among them, nitrogen-doped helicenes (azahelicenes) and their heteroatom-co-doped counterparts – such as B/N-, O/N-, S/N-, and Se/N-doped helicenes – have emerged as highly
  • helicenes. Particular attention is given to multi-heteroatom systems co-doped with elements such as boron, oxygen, sulfur, and selenium, highlighting their influence on CPL performance and structure–property relationships. We classify the nitrogen-doped helicenes into only N-containing helicenes, B,N
  • , thereby advancing their application in multifunctional chiral photonic and sensing platforms. In 2025, Gryko’s group synthesized a series of heterohelicenes 34a–c, featuring a 1,4-dihydropyrrolo[3,2-b]pyrrole (DHPP) core [48] (Table 10). The compounds exhibit similar absorption and emission profiles
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Published 11 Jul 2025

Tautomerism and switching in 7-hydroxy-8-(azophenyl)quinoline and similar compounds

  • Lidia Zaharieva,
  • Vera Deneva,
  • Fadhil S. Kamounah,
  • Nikolay Vassilev,
  • Ivan Angelov,
  • Michael Pittelkow and
  • Liudmil Antonov

Beilstein J. Org. Chem. 2025, 21, 1404–1421, doi:10.3762/bjoc.21.105

Graphical Abstract
  • positions (2–6) in 7OHQ in respect of the value for the unsubstituted 7OHQ; changes of ΔE(K-E) (b), ΔE(KE-E) (c), and ΔE(KK-K) (d), all in kcal/mol, in 1 as a function of the substitution at a different position (2–6) in the 7-hydroxyquinoline part in respect of the corresponding values for unsubstituted 1
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Published 10 Jul 2025

Reactions of acryl thioamides with iminoiodinanes as a one-step synthesis of N-sulfonyl-2,3-dihydro-1,2-thiazoles

  • Vladimir G. Ilkin,
  • Pavel S. Silaichev,
  • Valeriy O. Filimonov,
  • Tetyana V. Beryozkina,
  • Margarita D. Likhacheva,
  • Pavel A. Slepukhin,
  • Wim Dehaen and
  • Vasiliy A. Bakulev

Beilstein J. Org. Chem. 2025, 21, 1397–1403, doi:10.3762/bjoc.21.104

Graphical Abstract
  • Chemistry for Metals and Molecules, Department of Chemistry, KU Leuven, Celestijnenlaan 200F, Leuven B-3001, Belgium 10.3762/bjoc.21.104 Abstract A one-step method has been developed for the preparation of 2,3-dihydro-2-sulfonyl-3,4,5-substituted 1,2-thiazoles by the reaction of acryl thioamides and
  • used for the synthesis of a number of 2,3-dihydro-N-sulfonyl-1,2-thiazoles 3 (Scheme 2, method A). The conditions described in entry 12 (Table 1; Scheme 2, method B) are also noteworthy, since they do not require the preliminary synthesis of iodonium salts 2, which saves time and effort, however, the
  • ). Using the optimal reaction conditions (method A), twenty-seven 2,3-dihydro-N-sulfonyl-1,2-thiazoles 3 were synthesized in 69–96% yields (Scheme 2, method A). According to method B (Scheme 2), five compounds 3aa–ae were obtained in moderate yields (40–70%). The formation of the final compounds starts by
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Published 10 Jul 2025

N-Salicyl-amino acid derivatives with antiparasitic activity from Pseudomonas sp. UIAU-6B

  • Joy E. Rajakulendran,
  • Emmanuel Tope Oluwabusola,
  • Michela Cerone,
  • Terry K. Smith,
  • Olusoji O. Adebisi,
  • Adefolalu Adedotun,
  • Gagan Preet,
  • Sylvia Soldatou,
  • Hai Deng,
  • Rainer Ebel and
  • Marcel Jaspars

Beilstein J. Org. Chem. 2025, 21, 1388–1396, doi:10.3762/bjoc.21.103

Graphical Abstract
  • new natural products, pseudomonins D–G (1–4) isolated alongside other three known compounds, pseudomonine (5), pseudomonin B (6) and salicylic acid (7), were elucidated based on high-resolution mass spectrometry, 1D and 2D NMR analyses. The absolute configurations of the threonine residue in compounds
  • isolation of five phenolic siderophores with some of them exhibiting antimicrobial properties, including pseudomonins A–C and pseudomobactins A and B [15]. In this study we report the isolation and structural characterization of two previously undescribed as natural products (1 and 2) and two new compounds
  • (3 and 4) isolated alongside three known compounds, pseudomonine (5), pseudomonin B (6) and salicylic acid (7) [15] from the Pseudomonas sp. UIAU-6B strain by altering the fermentation conditions using an open system shaker at room temperature [16][17][18]. Results and Discussion The bacterial strain
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Published 04 Jul 2025

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

Graphical Abstract
  • reactions were carried out at 80 °C and at (a) 3.8 kbar, 1 h, (b) 2.8 kbar, 30 × 1 min cycles, (c) 2.8 kbar, 40 × 1 min cycles. The yields were determined by GC. High pressure-initiated large scale syntheses of N-aryl- and N-alkylpyrroles at about 100 g scale. Optimization of the HHP-initiated synthesis of
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Published 02 Jul 2025

Oxetanes: formation, reactivity and total syntheses of natural products

  • Peter Gabko,
  • Martin Kalník and
  • Maroš Bella

Beilstein J. Org. Chem. 2025, 21, 1324–1373, doi:10.3762/bjoc.21.101

Graphical Abstract
  • ], oxetanocin A [22], oxetin [23], merrilactone A [24], dictyoxetane [25] and mitrephorone A [26], which were isolated by 2005, but the collection is still being expanded and more recent additions include dichrocephone B from 2013 [27], compositacin D from 2017 [28], hawaiienol A from 2018 [29] or dendroterpene
  • categorised into 6 synthetic strategies as depicted in Scheme 1: a) C–O bond-forming cyclisations, b) C–C bond-forming cyclisations, c) [2 + 2] cycloadditions between carbonyls and alkenes, d) ring expansions, e) ring contractions and f) O–H insertions. In the following subchapters, these strategies will be
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Published 27 Jun 2025

Recent advances in amidyl radical-mediated photocatalytic direct intermolecular hydrogen atom transfer

  • Hao-Sen Wang,
  • Lin Li,
  • Xin Chen,
  • Jian-Li Wu,
  • Kai Sun,
  • Xiao-Lan Chen,
  • Ling-Bo Qu and
  • Bing Yu

Beilstein J. Org. Chem. 2025, 21, 1306–1323, doi:10.3762/bjoc.21.100

Graphical Abstract
  • transfer (HAT) in photocatalytic reactions. These radicals display exceptional selectivity and efficiency in abstracting hydrogen atoms from C–H, Si–H, B–H, and Ge–H, positioning them as invaluable tools in synthetic chemistry. This review summarizes the latest advancements in the photocatalyzed generation
  • and the relatively green chemistry of generating amidyl radicals. Amidyl radicals offer several advantages that enhance their applicability in organic synthesis: 1) The BDE of amidyl N–H bond is more than 105 kcal/mol, relative to the bond (C–H, Si–H, B–H, and Ge–H) which BDE is lower than 100 kcal
  • amidyl radicals from HRP: (a) direct single-electron oxidation of amide HRP in the presence of photocatalyst and a base via a proton-coupled electron transfer (PCET) process by the cleavage of the N–H bond; (b) single-electron reduction of HRP catalyzed by photocatalyst via a single-electron transfer
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Published 27 Jun 2025

Recent advances and future challenges in the bottom-up synthesis of azulene-embedded nanographenes

  • Bartłomiej Pigulski

Beilstein J. Org. Chem. 2025, 21, 1272–1305, doi:10.3762/bjoc.21.99

Graphical Abstract
  • antiaromatic character of the pentagon, in contrast to pristine azulene. This results in a significantly red-shifted optical absorption at 997 nm. Therefore, compound 24 should be considered a formally antiaromatic extended indeno[1,2-b]fluorene, rather than a ‘true’ extended azulene. Similarly, Müllen and co
  • with a low singlet−triplet gap. Nanographene 26, which also contains the indeno[1,2-b]fluorene structural motif, displays an extremely narrow energy gap of 0.27 eV and exhibits a pronounced open-shell biradical character, with biradical character index close to 1 (y0 = 0.92). Very recently, a similar
  • products containing either two (63) or four azulene subunits (64). Analysis of NICS values revealed that the formally antiaromatic character indeno[1,2-b]fluorene units remain dominant in fused PAHs 63 and 64 resulting also in a biradical character. Considering these factors, PAHs 63 and 64 should be
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Published 26 Jun 2025

Recent advances in oxidative radical difunctionalization of N-arylacrylamides enabled by carbon radical reagents

  • Jiangfei Chen,
  • Yi-Lin Qu,
  • Ming Yuan,
  • Xiang-Mei Wu,
  • Heng-Pei Jiang,
  • Ying Fu and
  • Shengrong Guo

Beilstein J. Org. Chem. 2025, 21, 1207–1271, doi:10.3762/bjoc.21.98

Graphical Abstract
  • radical A. This is followed by the conversion of a substrate containing C(sp3)–H bonds adjacent to an oxygen atom into an alkyl radical intermediate B. The alkyl radical intermediate then adds to the C=C bond of N-arylacrylamide, generating a second alkyl radical intermediate C, which undergoes
  • . This alkyl radical then adds across the C–C double bond in the enyne, forming an alkyl radical intermediate B, which reacts with the C–C triple bond to generate a vinyl radical intermediate C. Depending on the substitution effect at the 3-position of the acrylamide moiety, the intermediate undergoes
  • -determining step. Based on these results, a detailed mechanism was proposed (Scheme 10) in which a copper-assisted homolysis of DCP generates a cumyloxyl radical A, which initiates the formation of an imidoyl radical B from the isocyanide. This radical then undergoes homolytic cleavage to yield an alkyl
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Published 24 Jun 2025

Optimized synthesis of aroyl-S,N-ketene acetals by omission of solubilizing alcohol cosolvents

  • Julius Krenzer and
  • Thomas J. J. Müller

Beilstein J. Org. Chem. 2025, 21, 1201–1206, doi:10.3762/bjoc.21.97

Graphical Abstract
  • chlorides 2 and 2-methyl-N-benzylbenzothiazolium salts 3 in 1,4-dioxane as a solvent at room temp for 0.5 to 1 h produces representative aroyl-S,N-ketene acetals 1 in mostly excellent yield (Scheme 3). For comparison, the yields of the products 1 under standard (A) and new modified (B) conditions are listed
  • in Table 1. The yield of compounds 1 after flash chromatography on silica gel under modified conditions (B) are significantly higher than under standard conditions (A). The results demonstrate the broad applicability of the optimized reaction conditions. Acid chlorides with electron-withdrawing (-CN
  • ) and will be applied in future sequences for the generation of (hetero)aroyl-S,N-ketene acetals. Experimental Synthesis of compound 1i according to conditions B (typical procedure): 4-Fluorobenzoyl chloride (2e, 0.590 mL, 4.99 mmol, 1.00 equiv) and benzothiazolium salt 3a (1.76 g, 5.50 mmol, 1.10 equiv
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Published 20 Jun 2025

Synthesis of β-ketophosphonates through aerobic copper(II)-mediated phosphorylation of enol acetates

  • Alexander S. Budnikov,
  • Igor B. Krylov,
  • Fedor K. Monin,
  • Valentina M. Merkulova,
  • Alexey I. Ilovaisky,
  • Liu Yan,
  • Bing Yu and
  • Alexander O. Terent’ev

Beilstein J. Org. Chem. 2025, 21, 1192–1200, doi:10.3762/bjoc.21.96

Graphical Abstract
  • Alexander S. Budnikov Igor B. Krylov Fedor K. Monin Valentina M. Merkulova Alexey I. Ilovaisky Liu Yan Bing Yu Alexander O. Terent'ev N. D. Zelinsky Institute of Organic Chemistry of the Russian Academy of Sciences, 47 Leninsky prosp., 119991 Moscow, Russian Federation M. V. Lomonosov Moscow State
  • radicals and product 3 can be described by several pathways. The direct oxidation of 2 by Cu(II) A leads to the formation of P-centered radical E and Cu(I) B. Under air atmosphere, the formed Cu(I) species B can react with molecular oxygen resulting in the formation of peroxycopper intermediate C [75][76
  • hydroperoxide transfer from copper complex D with the formation of intermediate H and, therefore, regenerating Cu(I) B. Alternatively, the latter can be formed by oxidation of benzylic radical G with the formation of carbocation I. However, given that in the absence of oxygen the β-ketophosphonate was formed
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Published 20 Jun 2025

Selective monoformylation of naphthalene-fused propellanes for methylene-alternating copolymers

  • Kenichi Kato,
  • Tatsuki Hiroi,
  • Seina Okada,
  • Shunsuke Ohtani and
  • Tomoki Ogoshi

Beilstein J. Org. Chem. 2025, 21, 1183–1191, doi:10.3762/bjoc.21.95

Graphical Abstract
  • electrophilic functionalization. a) Synthesis of methylene-alternating copolymers of fully π-fused propellanes. DCE, 1,2-dichloroethane. b) 1H NMR (500 MHz, top) and 13C (126 MHz, bottom) NMR spectra of [4.3.3]_CH2OH and [4.3.3]_linear in CDCl3 at room temperature. Gas adsorption (filled circles) and desorption
  • (open circles) isotherms of [3.3.3]_oligo (dark red), [3.3.3]_linear (red), [3.3.3]_branch (orange), [4.3.3]_oligo (purple), [4.3.3]_linear (blue), and [4.3.3]_branch (green). a) CO2 at 298 K and b) N2 at 77 K. Formylation of naphthalene-fused propellanes. Properties of methylene-alternating
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Published 18 Jun 2025

Enhancing chemical synthesis planning: automated quantum mechanics-based regioselectivity prediction for C–H activation with directing groups

  • Julius Seumer,
  • Nicolai Ree and
  • Jan H. Jensen

Beilstein J. Org. Chem. 2025, 21, 1171–1182, doi:10.3762/bjoc.21.94

Graphical Abstract
  • SMARTS pattern match than highlighted in Tomberg and colleagues [9]. The matching SMARTS pattern from Tomberg et al. [9] is shown in (a), whereas our algorithm resulted in the match shown in (b). An example highlighting the difficulties in prioritizing the SMARTS patterns. All three patterns match the
  • black cross. B: Distribution of correct (green), semi-correct (yellow), and wrong (red) predictions for the same molecules, evaluated with an energy threshold of 1.0 kcal·mol−1. Molecules with five potential reaction sites that are predicted wrong by the QM workflow. The experimentally observed and
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Published 16 Jun 2025

A multicomponent reaction-initiated synthesis of imidazopyridine-fused isoquinolinones

  • Ashutosh Nath,
  • John Mark Awad and
  • Wei Zhang

Beilstein J. Org. Chem. 2025, 21, 1161–1169, doi:10.3762/bjoc.21.92

Graphical Abstract
  • reaction followed by the cleavage of the alkyl group to give intermediate II as a free amine. Annulation of II with CDI gave product B which is an HIV reverse transcriptase inhibitor (Scheme 1B) [17]. We have reported a three-component [3 + 2] cycloaddition followed by IMDA reaction for making heterocyclic
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Published 13 Jun 2025

Synthetic approach to borrelidin fragments: focus on key intermediates

  • Yudhi Dwi Kurniawan,
  • Zetryana Puteri Tachrim,
  • Teni Ernawati,
  • Faris Hermawan,
  • Ima Nurasiyah and
  • Muhammad Alfin Sulmantara

Beilstein J. Org. Chem. 2025, 21, 1135–1160, doi:10.3762/bjoc.21.91

Graphical Abstract
  • derivatives named alphabetically starting from the original borrelidin 1, designated as borrelidin A (Table 1, entry 1). A rare nitrile moiety at C12 of the macrolide ring in borrelidin A is present in most members of the borrelidin family (Table 1, entries 4, 5, 7–11, 13–16, and 18), except for borrelidin B
  • , N-acetylborrelidin B, borrelidin CR2, borrelidin I, and borrelidin N (Table 1, entries 2, 3, 6, 12, and 17). Borrelidin B (Table 1, entry 2), a tetrahydroborrelidin derivative with an aminomethyl group instead of the nitrile in position 12 of the macrolide, was isolated from the marine-derived
  • Streptomyces sp. RL09-241-NTF-B strain [17]. The discovery of borrelidin B, along with the novel introduction of an N-acetyl group in borrelidin B (N-acetylborrelidin B, Table 1, entry 3), expanded the borrelidin family. N-Acetylborrelidin B was obtained from Streptomyces mutabilis sp. MII [18], a marine
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Published 12 Jun 2025

Investigations of amination reactions on an antimalarial 1,2,4-triazolo[4,3-a]pyrazine scaffold

  • Henry S. T. Smith,
  • Ben Giuliani,
  • Kanchana Wijesekera,
  • Kah Yean Lum,
  • Sandra Duffy,
  • Aaron Lock,
  • Jonathan M. White,
  • Vicky M. Avery and
  • Rohan A. Davis

Beilstein J. Org. Chem. 2025, 21, 1126–1134, doi:10.3762/bjoc.21.90

Graphical Abstract
  • C20H2635ClN6NaO2, 439.1620; found, 439.1616. (A) Position numbering on the pyrazine ring of 1,2,4-triazolo[4,3-a]pyrazine. (B) Illustration of ipso- and tele-substitution products for reactions of nucleophiles with 5-halogenated 1,2,4-triazolo[4,3-a]pyrazine, where X = halogen and Nuc = nucleophile. Key COSY
  • (–), HMBC (→) and ROESY (↔) correlations for compound 2. Thermal ellipsoid plot of compound 2. Thermal ellipsoid plots for compounds 7 (A), 10 (B) and 15 (C). Treatment of 1 with phenethylamine (PEA) under two different reaction conditions, (i) or (ii), gave 2 in 70% and 82% yield, respectively. Reagents
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Published 10 Jun 2025

Gold extraction at the molecular level using α- and β-cyclodextrins

  • Susana Santos Braga

Beilstein J. Org. Chem. 2025, 21, 1116–1125, doi:10.3762/bjoc.21.89

Graphical Abstract
  • -CD·HAuBr4·DBC, showing the packing mode and dimensions of the complex. (b) Capped-stick and space-filling representation of the β-CD channels extending along the c-axis, which are occupied by alternating DBC and [AuBr4]− anions. Solvent molecules and hydrogen atoms have been omitted for the sake of clarity
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Published 06 Jun 2025

A versatile route towards 6-arylpipecolic acids

  • Erich Gebel,
  • Cornelia Göcke,
  • Carolin Gruner and
  • Norbert Sewald

Beilstein J. Org. Chem. 2025, 21, 1104–1115, doi:10.3762/bjoc.21.88

Graphical Abstract
  • broad doublets instead of double-doublets (Figure 2a,b). The lack of a second coupling constant indicates a conformation in between a chair and a boat with a dihedral angle ϕ near 90°, which is necessary for a coupling constant to be around 0 Hz. Half-chair or twist-boat conformations are well known for
  • -S) and 3J(H2,H3,pro-R). Therefore, a half-chair conformation with ϕ(H2,H3,pro-S) = 90° and ϕ(H6,H5,pro-R) = 270° resulting in 3J(H2,H3,pro-S) = 3J(H6,H5,pro-R) ≈ 0 Hz and 3J(H2,H3,pro-R) = 5.0 Hz as well as 3J(H6,H5,pro-S) = 5.7 Hz (as shown in Figure 2a,b) would be the most suitable explanation
  • for H2 and H6. 1H NMR spectra with both signal sets for the chair and half-chair configuration as well as Newman projection for both protons H2 and H6 with corresponding dihedral angles ϕ for a) (2R,6S)-9, b) saponification product (2R,6S)-10. 1H NMR spectra with signal set for the chair configuration
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Published 04 Jun 2025

Supramolecular assembly of hypervalent iodine macrocycles and alkali metals

  • Krishna Pandey,
  • Lucas X. Orton,
  • Grayson Venus,
  • Waseem A. Hussain,
  • Toby Woods,
  • Lichang Wang and
  • Kyle N. Plunkett

Beilstein J. Org. Chem. 2025, 21, 1095–1103, doi:10.3762/bjoc.21.87

Graphical Abstract
  • help assemble higher order supramolecular hypervalent iodine macrocycles [16][17][18]. Examples of hypervalent iodine macrocycles (HIMs) include those synthesized by Ochiai [16], Tykwinski and Zhdankin [17], and our group’s extension of those works (Figure 1A and B) [18][19]. The main driving force for
  • 7.750 ppm (compound 1, proton b, Figure 3A) shifting upfield and the multiplet at 7.60 ppm (protons c and d, Figure 3A) shifting downfield and merging into a single multiplet when approximately 1:1 ratio of HIM to salt was added as shown in Figure 4. Additional titration data are provided in Supporting
  • macrocycle and not to the electrophilic, yet oxygen-rich, core of the macrocycle. (A) Our previous work: Assembly and disassembly of phenylalanine hypervalent iodine macrocycles (Phe HIM) through anion coordination. (B) Another work on π-extended hypervalent iodine macrocycle and their supramolecular
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Published 30 May 2025

Salen–scandium(III) complex-catalyzed asymmetric (3 + 2) annulation of aziridines and aldehydes

  • Linqiang Wang and
  • Jiaxi Xu

Beilstein J. Org. Chem. 2025, 21, 1087–1094, doi:10.3762/bjoc.21.86

Graphical Abstract
  • carboxylate groups followed by a ring opening of the aziridine ring, forming azomethine ylide intermediates A. The intermediates A further undergo a [2 + 3] annulation (or cycloaddition) with aldehydes 2 through endo transition state TS to generate intermediates B, which release products 3 with regeneration
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Published 28 May 2025

Recent advances in synthetic approaches for bioactive cinnamic acid derivatives

  • Betty A. Kustiana,
  • Galuh Widiyarti and
  • Teni Ernawati

Beilstein J. Org. Chem. 2025, 21, 1031–1086, doi:10.3762/bjoc.21.85

Graphical Abstract
  • vinylphenylboronic acid to synthesize the solid-supported phenylboronic acid catalyst (cat 1) which was used to convert cinnamic acid (7) to its corresponding amide 12 in moderate yield. The reaction involves dicarboxylate complex 135 formed through Lewis acid B–O=C interaction (Scheme 41A) [23]. The catalyst could
  • be reused multiple times without significant loss of activity. Using B(C6F5)3 as catalyst, Wu and co-workers (2021) developed a borane-catalyzed Fischer esterification of cinnamic acids with methanol to afford the corresponding methyl cinnamates 136 and 137 via (C6F5)3B–O=C interaction (138) (Scheme
  • -branched (L/B) selectivity of >20:1. The reaction involves the formation of palladium hydride (Pd–H) 270 as the key species followed by alkyne and CO insertion reactions via 271 and 272 (Scheme 68A) [116]. On the one hand, Jia and co-workers (2021) utilized environmentally benign water as the hydrogen
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Published 28 May 2025

Biobased carbon dots as photoreductants – an investigation by using triarylsulfonium salts

  • Valentina Benazzi,
  • Arianna Bini,
  • Ilaria Bertuol,
  • Mariangela Novello,
  • Federica Baldi,
  • Matteo Hoch,
  • Alvise Perosa and
  • Stefano Protti

Beilstein J. Org. Chem. 2025, 21, 1024–1030, doi:10.3762/bjoc.21.84

Graphical Abstract
  • solution was examined, for solubility reasons. a) CDs-mediated 1,2-difunctionalization of alkenes by alkyl halides R–Y and b) light-driven reduction of triarylsulfonium salts in the presence of CDs. Carbon dots tested in this project and their main (photo)physical characteristics. Emission parameters for
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Published 26 May 2025

Synthesis of pyrrolo[3,2-d]pyrimidine-2,4(3H)-diones by domino C–N coupling/hydroamination reactions

  • Ruben Manuel Figueira de Abreu,
  • Robin Tiedemann,
  • Peter Ehlers and
  • Peter Langer

Beilstein J. Org. Chem. 2025, 21, 1010–1017, doi:10.3762/bjoc.21.82

Graphical Abstract
  • instance, deazapurines represent heterocyclic fused pyrimidine bases which have found special attention, due to their widespread occurrence in natural alkaloids exhibiting various biological properties. For example, cadeguomycin (A), tubercidin (B), and toyocamycin (C) show antibiotic properties, while
  • activities. Development of drugs based on pyrrolopyrimidines: A: Cadeguomycin. B: Tubercidin. C: Toyocamycin. D: Batzelladine A. E: Sangivamycin. F: Pemetrexed. G: Immucillin H. H: TAK-285 (tyrosine kinase inhibitor). UV–vis absorption (left) and emission (right, λex = 300 nm) spectra of compounds 4a, 4j, 4k
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Published 22 May 2025
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