Origami with small molecules: exploiting the C–F bond as a conformational tool

• Patrick Ryan,
• Ramsha Iftikhar and
• Luke Hunter

Beilstein J. Org. Chem. 2025, 21, 680–716, doi:10.3762/bjoc.21.54

• oriented antiparallel to another dipole within the molecule, or in which the fluorine atom is located close to a positively charged atom, will be stabilised. Third, the C–F bond has a low-lying σ* antibonding orbital, the larger lobe of which is located behind the carbon atom. This empty orbital is

• fluorinated motif with its gauche-aligned C–F bonds [22]. We will now consider what happens when fluorine is introduced into the middle of an alkyl chain. If two fluorines are attached to the same carbon (i.e., a 1,1-difluoro pattern), a subtle but important perturbation occurs to the shape of the alkyl chain

• this phenomenon is provided by Bent’s rule [24], which predicts that the C–F bonds will have greater p character and the C(F2)–C bonds will have greater s character, with an accompanying deviation of the central carbon atom away from a perfectly tetrahedral shape. A functional outcome of C–C(F2)–C

Recent advances in allylation of chiral secondary alkylcopper species

• Minjae Kim,
• Gwanggyun Kim,
• Doyoon Kim,
• Jun Hee Lee and
• Seung Hwan Cho

Beilstein J. Org. Chem. 2025, 21, 639–658, doi:10.3762/bjoc.21.51

• significance of this transformation lies in its unique ability to efficiently create a stereogenic center while forming new carbon–carbon or carbon–heteroatom bonds (e.g., C–N, C–O, and C–S) with excellent selectivities. The field of metal-catalyzed allylic substitution has evolved significantly since its

• into a powerful and versatile tool in asymmetric synthesis, capable of employing a wide array of organometallic reagents that furnish the desired compounds with high efficiency and selectivity. The regioselective asymmetric construction of stereogenic carbon centers from prochiral allylic substrates

• largely depends on the choice of the nucleophilic organometallic species (Scheme 2). For example, the asymmetric copper-catalyzed allylic alkylation utilizing organometallic species 5 bearing a primary carbon–metal bond predominantly constructs the stereogenic center derived from electrophiles. The

Entry to 2-aminoprolines via electrochemical decarboxylative amidation of N‑acetylamino malonic acid monoesters

• Olesja Koleda,
• Janis Sadauskis,
• Darja Antonenko,
• Edvards Janis Treijs,
• Raivis Davis Steberis and
• Edgars Suna

Beilstein J. Org. Chem. 2025, 21, 630–638, doi:10.3762/bjoc.21.50

• addressed. Initially, we hypothesized that 11a may form by a single-electron oxidation/decarboxylation (Kolbe reaction) of 9a to generate carbon-centered radical, followed by hydrogen abstraction from solvent. To verify the hypothesis, an electrolysis of acid 9d was performed under optimized conditions

• observed by LC–MS when the electrolysis was performed in 5:1 MeCN/D2O (Scheme 2, reaction 2). The considerably higher O–H bond dissociation energy (119 kcal/mol) [12] as compared to that of the C–H bond in MeCN (86 kcal/mol) [13] renders the hydrogen atom abstraction from water by a carbon-centered radical

• column chromatography. Cyclic voltammetry studies CV experiments were carried out in an SVC-2 (ALS, Japan) three-electrode cell using a PalmSens4 (PalmSens). A glassy carbon disk (diameter: 1.6 mm) served as the working electrode and a platinum wire as the counter electrode. The glassy carbon disk was

Semisynthetic derivatives of massarilactone D with cytotoxic and nematicidal activities

• Rémy B. Teponno,
• Sara R. Noumeur and
• Marc Stadler

Beilstein J. Org. Chem. 2025, 21, 607–615, doi:10.3762/bjoc.21.48

• molecular ion at m/z 633.2077 [M + H]+ (calcd. for C38H32O9+: 633.2119). This implies that compound 4 has 390 more atomic mass units than massarilactone D, suggesting the presence of three additional cinnamoyl groups. The presence of three cinnamoyl moieties was supported by carbon signals observed at δC

• signals observed at δH 6.92 (dddd, J = 8.5, 7.1, 5.6, 1.5 Hz, H-3'), 1.81 (dq, J = 7.1, 1.2 Hz, 3H-4'), and 1.77 (q, J = 1.2 Hz, 3H-5') as well as carbon resonances depicted at δC 165.6 (C-1'), 141.0 (C-3'), 128.8 (C-2'), 14.7 (C-4'), and 12.0 (C-5'). Due to the upfield shifts of H-3 (δH 3.82, dd, J = 5.1

Total synthesis of (±)-simonsol C using dearomatization as key reaction under acidic conditions

• Xiao-Yang Bi,
• Xiao-Shuai Yang,
• Shan-Shan Chen,
• Jia-Jun Sui,
• Zhao-Nan Cai,
• Yong-Ming Chuan and
• Hong-Bo Qin

Beilstein J. Org. Chem. 2025, 21, 601–606, doi:10.3762/bjoc.21.47

• synapse growth and inhibits acetylcholinesterase. (±)-Simonsol C (Figure 1) has received considerable attention due to the presence of an aryl- and allyl-containing quaternary carbon center, which is common in natural products such as galanthamine and morphine. To construct the quaternary carbon in

• carbon center. In the first report on the total synthesis of simonsol C (Scheme 1), in 2016 Banwell’s group employed an intramolecular Heck reaction as key step to furnish the aryl-containing quaternary center and simultaneously construct the benzofuran skeleton [7]. This synthesis involved a total of 12

• ] and has been used in syntheses of natural products containing aryl quaternary carbon centers [9][10]. Unlike the intramolecular alkylation strategy of a phenol derivative, which can only be applied in basic dearomatization reactions, our approach using an α-iodophenol ether as precursor of the

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

• carbon atom, due to the readiness for losing a water molecule. Formaldehyde is commonly used in its polymeric form (paraformaldehyde) or in a 37% aqueous solution (formalin). The exceptional solubility of formaldehyde in water or biobased solvents, such as ethanol and glycerol, enhances the feasibility

• . Application of glyoxylate derivatives in post-cyclization reactions as a C1 building block Glyoxylate derivatives have been used in Ugi- and Passerini-type reactions, since the adduct generated in both cases has two reactive centers for post-cyclization possibilities: the ester moiety and the α-carbon to the

• ][101][102][103][104]), or with a carbanion generated by a strong base in an Ugi/Dieckmann cyclization [105]. In all these cases, the glyoxylate derivative incorporates two carbon atoms into the final product, thus serving as a C2-building block. Similarly, the ester group increases the acidity of 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

• established by X-ray analysis. The proposed mechanism of the considered processes is outlined at Scheme 8. Initially, the free nitrogen nucleophile is reversibly generated from the corresponding hydrochloride or acetate. Next, acid-catalyzed addition of the amine component to the carbon atom of the aroyl

Asymmetric synthesis of β-amino cyanoesters with contiguous tetrasubstituted carbon centers by halogen-bonding catalysis with chiral halonium salt

• Yasushi Yoshida,
• Maho Aono,
• Takashi Mino and
• Masami Sakamoto

Beilstein J. Org. Chem. 2025, 21, 547–555, doi:10.3762/bjoc.21.43

• , which formed the corresponding products in high to excellent enantioselectivities. In this paper, the asymmetric synthesis of β-amino cyanoesters with contiguous tetrasubstituted carbon stereogenic centers by the Mannich reaction through chiral halonium salt catalysis is presented, which provided the

• corresponding products in excellent yields with up to 86% ee. To the best of our knowledge, the present paper is the first to report the asymmetric construction of β-amino cyanoesters with contiguous tetrasubstituted carbon stereogenic centers by the catalytic Mannich reaction. Keywords: asymmetric catalysis

• tetrasubstituted carbon stereogenic centers [42][43][44][45][46]. In 2011, Shibasaki, Matsunaga and co-workers reported strontium or magnesium-catalyzed stereodivergent asymmetric Mannich reactions of an α-isothiocyanato ester with ketimines, which provided the products in excellent yields and

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

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

• reacts with hydrazine hydrate and is heated to reflux, forming a pyrazolinone 2. This product is then chlorinated at the α-carbon, introducing a leaving group, to yield 3. The parent pyrazolinone 3 is subsequently treated with a base (either K2CO3 or N,N-diisopropylethylamine) to form the bimane 4. For

• is 0(0°), indicating that the reacting double bonds are coplanar and parallel. Furthermore, the intermolecular distances between the reacting carbons are identical. The distance between two carbon double bonds in Cl2B (B) was determined to be 3.487(4) Å (Table 1). The key question is why did Cl2B

• refined isotropic on calculated positions using a riding model with their Uiso values constrained to 1.5 times the Ueq of their pivot atoms for terminal sp3 carbon atoms and 1.2 times for all other carbon atoms. Disordered moieties were refined using bond length restraints and displacement parameter

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

• provided the corresponding amino-substituted N-acetyl diazocine 21 (Scheme 1). Another option for carbon–heteroatom bond formation reactions are copper-catalyzed Ullmann-type reactions, which have already been applied to the parent diazocine [36][37]. The attempted synthesis of azide-functionalized N

Organocatalytic kinetic resolution of 1,5-dicarbonyl compounds through a retro-Michael reaction

• James Guevara-Pulido,
• Fernando González-Pérez,
• José M. Andrés and
• Rafael Pedrosa

Beilstein J. Org. Chem. 2025, 21, 473–482, doi:10.3762/bjoc.21.34

• organometallic catalysis [15], enzymatic catalysis [16], aminocatalysis [17][18][19], and hydrogen-bonding catalysis [20][21][22]. The Michael addition reaction is a versatile synthetic methodology that allows the formation of new carbon–carbon and carbon–heteroatom bonds through the coupling of electron-poor

• recorded in CDCl3 or acetone-d6. Chemical shifts for protons are reported in ppm from tetramethylsilane as an internal reference. Chemical shifts for carbons are reported in ppm from tetramethylsilane and referenced to the solvent's carbon resonance. Specific rotations were measured using a 5 mL cell with

Photomechanochemistry: harnessing mechanical forces to enhance photochemical reactions

• Francesco Mele,
• Ana M. Constantin,
• Andrea Porcheddu,
• Raimondo Maggi,
• Giovanni Maestri,
• Nicola Della Ca’ and
• Luca Capaldo

Beilstein J. Org. Chem. 2025, 21, 458–472, doi:10.3762/bjoc.21.33

• yield of 79%. Scanning electron microscopy (SEM) analysis revealed the deformation and reduction in size of SAOED particles upon milling. Interestingly, carbon determination experiments revealed that SAOED is quickly poisoned by organic matter, thus hampering recyclability. This can be to some extent

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

• -tetrafluorobenzene as an internal standard. Isolated yields are given in parentheses. A: Background and iR drop-corrected CVs of 5 mM 4a at different scan rates (solvent: HFIP, working electrode: glassy carbon, supporting electrolyte: 0.1 M TBA-BF4). B: Plot of the peak current densities (jp) vs v0.5. C

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

• therefore non-aromatic. Even when fused with benzene via a C–C bond, pyrazoline remains non-aromatic, which is the case of indazoline. Icosahedral carboranes are globular molecular clusters made of carbon and boron, displaying 3D aromaticity [12][13][14][15]. Their unique properties – such as aromaticity

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

• glycochemists. The protecting building blocks on the glycosides contribute significantly in attaining the required stereochemistry of the resulting glycosides. Strategic installation of suitable protecting groups in the C-2 position, vicinal to the anomeric carbon, renders neighbouring group participation

• , whereas protecting groups in the distal C-3, C-4, and C-6 positions are often claimed to exhibit remote group participation with the anomeric carbon. Neighbouring group participation and remote group participation are being widely studied to help the glycochemists design the synthetic protocols for

• the inversion at the anomeric sp3 carbon centre by the attack of the acceptor moiety. Crich β-mannosylations are classic illustrations for the same [38][39]. On the other hand, the stability of the carbocation contributes towards the reaction to proceed via the dissociative two-step SN1 reaction

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

• spectrum of 7a, a correlation of the NH proton with the bridging carbon atoms C(3a'), C(9b'), and the quaternary carbon atom C(1') of the indolenine fragment is observed with δH 136.6 ppm, 134.0 ppm, and 53.6 ppm, respectively (Supporting Information File 2, Figure S20). The most important HMBC

• , no correlations of the down-field proton with the carbon atoms of the indolenine fragment are observed (Supporting Information File 2, Figures S21 and S22). Thus, in CDCl3, compound 7a is predominantly in the (OH) tautomeric form. The structure of 2-(3,3-dimethyl-3H-benzo[g]indolin-2-yl)-5,6,7

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

• methylene at 67.7–68.0 ppm, one N-methyl at 38.1–38.2 ppm, and one carbonyl carbon signal at 166.5–167.6 ppm. Also for compounds 7i–n, distinct 13C NMR chemical shifts were observed: two methylene carbon resonances at 54.7–68.2 ppm, one N-methyl at 37.9–38.0 ppm, and two carbonyl carbon signals at 165.2

• –166.7 ppm. Aromatic carbon chemical shifts for both sets of derivatives 7a–h and 7i–n were found in the range of 109.1–156.0 ppm. In vitro antimicrobial and SAR analysis Microbroth single dose antimicrobial assays were performed against different pathogens including susceptible Staphylococcus aureus

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

• spectrum to two sp3 carbon atoms at δC 67.8 (C-2') and 72.6 (C-3'), respectively. These results suggested that compound 1 possesses a tetramic acid moiety similar to prototenellin D (Figure 1), a precursor in the biosynthesis of tenellin [10], a 2-pyridone derivative purified from the entomopathogenic

• ketocarbonyl carbon at δC 192.9 (C-1') confirming the presence of a hydroxy group at C-3' and to be as depicted in Figure 1. Further key HMBC correlations were recognized including those from an olefinic proton at δH 5.51 (d, J = 9.6 Hz, H-11) to one allylic methyl group at δH 1.77 (d, J = 1.2 Hz, H3-16) and

• one doublet methyl group at δH 0.94 (d, J = 6.6 Hz, H3-15) indicating its presence in the middle between both methyl groups. The latter together with a terminal triplet methyl group at δH 0.80 (t, J = 7.4 Hz, H3-14) further revealed key correlation to one tertiary and one secondary sp3 carbon atoms at

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

• the substrate, an activated ester 25, subsequently generating carbon-centered radicals without the need for sacrificial electron donors via a decarboxylation process. In reacting with electron-deficient alkenes or alkynes 26, these radicals further yield tetralin and dialin moieties 27, respectively

• , and heptamethin derivatives. The length of the polymethin chain has a pronounced effect on their absorption properties, with the addition of each conjugated carbon–carbon double bond causing a red shift of about 100 nm in the absorption spectrum. The formation of J-aggregates allows cyanin compounds

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

• derivatives. At first, a Lewis base attack at the α-position of the MBH nitrile of isatin resulted in the intermediate A with elimination of carbon dioxide and tert-butoxide ion. Secondly, the product 3 was produced by the SN2 substitution of the Lewis base by the arylamine. When MBH maleimides of isatin were

• used in the reaction, a direct Michael addition of the arylamine to the C=C bond of the maleimide unit and sequential elimination of carbon dioxide and tert-butoxide ion gives the intermediate B, which in turn undergoes an allylic rearrangement to afford the product 5. In this process, no extra

• addition of Lewis base is needed. When triphenylphosphine or tri(n-butyl)phosphine were involved in the reaction, the similar SN2’ substitution of tri(n-butyl)phosphine with the elimination of carbon dioxide and tert-butoxide anion gives the phosphonium salt C. Then, the deprotonation of phosphonium salt C

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

• Electrochemistry Cyclic voltammetry experiments were conducted with a three-electrode geometry operating with a glassy carbon as the working electrode. A Pt-coil counter electrode. and an Ag wire, as the pseudo-reference, were used. Potential values are given with respect to the ferrocene/ferrocenium (Fc/Fc

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

• Islam S. Marae Jingyun Tan Rengo Yoshioka Zakaria Ziadi Eugene Khaskin Serhii Vasylevskyi Ryota Kabe Xiushang Xu Akimitsu Narita Organic and Carbon Nanomaterials Unit, Okinawa Institute of Science and Technology Graduate University, 1919-1 Tancha, Onna-son, Kunigami-gun, Okinawa 904-0495, Japan

Synthesis of disulfides and 3-sulfenylchromones from sodium sulfinates catalyzed by TBAI

• Zhenlei Zhang,
• Ying Wang,
• Xingxing Pan,
• Manqi Zhang,
• Wei Zhao,
• Meng Li and
• Hao Zhang

Beilstein J. Org. Chem. 2025, 21, 253–261, doi:10.3762/bjoc.21.17

• Zhenlei Zhang Ying Wang Xingxing Pan Manqi Zhang Wei Zhao Meng Li Hao Zhang School of Chemistry and Material Engineering, Anhui Provincial Key Laboratory of Green Carbon Chemistry, Engineering Research Center of Biomass Conversion and Pollution Prevention of Anhui Educational Institutions, Biomass

• prevented their widespread use on a large scale. Recently, research efforts have focused on exploring alternative reagents that offer the advantages of being odorless and more stable than thiols. These alternatives include sulfonyl chloride [26], sulfonyl hydrazine [27], carbon disulfide [28], and sodium

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

• generated and followed using the keyword Guess (mix, always). The frequency calculation for the TS was carried out to confirm that there is only one imaginary frequency corresponding to the stretching vibration between the nitrogen and the carbon atoms at the reactive site. The frequency calculation for