Unique halogen–π association detected in single crystals of C–N atropisomeric N-(2-halophenyl)quinolin-2-one derivatives and the thione analogue

• Mai Uchibori,
• Nanami Murate,
• Kanako Shima,
• Tatsunori Sakagami,
• Ko Kanehisa,
• Gary James Richards,
• Akiko Hori and
• Osamu Kitagawa

Beilstein J. Org. Chem. 2025, 21, 1748–1756, doi:10.3762/bjoc.21.138

• diverse C–N atropisomeric compounds possessing carboxamide, imide, lactam, sulfonamide, indole, pyrrole, imidazole, carbazole and amine skeletons have been reported by many groups [1][2][3][4][5][6][7][8][9]. C–N atropisomers are attractive compounds from the viewpoint of not only synthetic organic

• interaction as an alternative to hydrogen bonding and has been widely used as an important supramolecular tool in broad fields such as materials science, crystal engineering, liquid crystals, synthetic organic chemistry and medicinal chemistry [22][23][24][25][26]. Typically, halogen bonding has been

Preparation of a furfural-derived enantioenriched vinyloxazoline building block and exploring its reactivity

• Madara Darzina,
• Anna Lielpetere and
• Aigars Jirgensons

Beilstein J. Org. Chem. 2025, 21, 1737–1741, doi:10.3762/bjoc.21.136

• Madara Darzina Anna Lielpetere Aigars Jirgensons Latvian Institute of Organic Synthesis Aizkraukles 21, Riga, LV-1006, Latvia Faculty of Natural Sciences and Technology, Riga Technical University, 3 P. Valdena Street, Riga LV-1048, Latvia 10.3762/bjoc.21.136 Abstract N-Alloc-protected furfuryl

Convenient alternative synthesis of the Malassezia-derived virulence factor malassezione and related compounds

• Karu Ramesh and
• Stephen L. Bearne

Beilstein J. Org. Chem. 2025, 21, 1730–1736, doi:10.3762/bjoc.21.135

• with EtOAc (3 × 50 mL) and the combined organic layers were washed with water (100 mL) and brine (100 mL), and then dried over anhydrous MgSO4. The solvent was removed under reduced pressure and the residue was purified by flash chromatography on silica gel (EtOAc/hexane gradient 1:10 → 1:1, 1% AcOH

• ), followed by brine (40 mL). The organic layer was dried over anhydrous Na2SO4, and the solvent was evaporated under reduced pressure. The residue was purified by flash chromatography on silica gel using a gradient of EtOAc/hexane (1:10 → 1:1), affording compound 23 as a colorless viscous oil (425 mg, 50

• ), then washed with water (2 × 40 mL) and brine (40 mL). The organic layer was dried over anhydrous Na2SO4, and the solvent was evaporated under reduced pressure. The resulting residue was subsequently purified by flash chromatography on silica gel using a hexane/ethyl acetate mixture as the eluent. 1,3

3,3'-Linked BINOL macrocycles: optimized synthesis of crown ethers featuring one or two BINOL units

• Somayyeh Kheirjou,
• Jan Riebe,
• Maike Thiele,
• Christoph Wölper and
• Jochen Niemeyer

Beilstein J. Org. Chem. 2025, 21, 1719–1729, doi:10.3762/bjoc.21.134

• Somayyeh Kheirjou Jan Riebe Maike Thiele Christoph Wolper Jochen Niemeyer Faculty of Chemistry (Organic Chemistry) and Center for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen, 45141 Essen, Germany Faculty of Chemistry (Inorganic Chemistry), University of Duisburg-Essen

Approaches to stereoselective 1,1'-glycosylation

• Daniele Zucchetta and
• Alla Zamyatina

Beilstein J. Org. Chem. 2025, 21, 1700–1718, doi:10.3762/bjoc.21.133

• Daniele Zucchetta Alla Zamyatina Department of Natural Sciences and Sustainable Resources, Institute of Organic Chemistry, BOKU University, 1190 Vienna, Austria 10.3762/bjoc.21.133 Abstract Nonreducing disaccharides are prevalent in non-mammalian glycans and glycolipids, serving as pivotal

Continuous-flow-enabled intensification in nitration processes: a review of technological developments and practical applications over the past decade

• Feng Zhou,
• Chuansong Duanmu,
• Yanxing Li,
• Jin Li,
• Haiqing Xu,
• Pan Wang and
• Kai Zhu

Beilstein J. Org. Chem. 2025, 21, 1678–1699, doi:10.3762/bjoc.21.132

• engaged in the development of continuous-flow nitration systems. Keywords: continuous-flow; kinetics; nitration; optimization; scale up; Introduction Nitro compounds hold an extremely important position in the field of organic chemistry, mainly because they are easily obtainable and can be converted

• compound production, fundamentally involving the interaction between organic substrates and nitrating reagents. The intrinsic kinetics of nitration processes are governed by the synergistic interplay between the substrate’s molecular architecture and nitrating reagent reactivity. Distinct substrate

• , safety, and efficiency concerns, researchers have explored various types of inorganic and organic nitrating reagents to improve reaction performance through innovative chemical approaches. Patra et al. comprehensively reviewed the development and applications of organic nitrating reagents in nitration

Influence of the cation in hypophosphite-mediated catalyst-free reductive amination

• Natalia Lebedeva,
• Fedor Kliuev,
• Olesya Zvereva,
• Klim Biriukov,
• Evgeniya Podyacheva,
• Maria Godovikova,
• Oleg I. Afanasyev and
• Denis Chusov

Beilstein J. Org. Chem. 2025, 21, 1661–1670, doi:10.3762/bjoc.21.130

• hypophosphorous acid are commercially available in bulk amounts, however, their usage is understudied in organic processes. While NaH2PO2 has proved to be an efficient four-electron reductant in the catalyst-free reductive amination, the influence of cation in hypophosphite salt has not been studied yet. This

• Scientific) and readily available in bulk quantities compound. In organic synthesis, it is most commonly used in metal-catalyzed reductions where NaH2PO2 serves as a molecular hydrogen donor [6][7][8][9][10][11][12][13][14][15][16]. However, recent studies demonstrated application of hypophosphites as a

• pH 0) [19], and usage of an additional amount of base leads to stronger reductive properties. Moreover, the role of the cation could be critical for the thermal stability against disproportionation or aerobic oxidation of hypophosphite [38]; salts with larger cations are also more soluble in organic

Catalytic asymmetric reactions of isocyanides for constructing non-central chirality

• Jia-Yu Liao

Beilstein J. Org. Chem. 2025, 21, 1648–1660, doi:10.3762/bjoc.21.129

• become a hot topic in synthetic organic chemistry. Isocyanides (also termed isonitriles) are a class of highly versatile building blocks in organic synthesis, participating in a wide range of transformations including multicomponent reactions (e.g., the well-known Passerini and Ugi reactions) [13][14][15

• transformations of isocyanides for generating architectures bearing axial, planar, helical, and inherent chirality. These advances not only offer efficient routes to enantioenriched non-central chiral compounds but also significantly broaden the utility of isocyanides in organic synthesis. Nevertheless, despite

Photocatalysis and photochemistry in organic synthesis

• Timothy Noël and
• Bartholomäus Pieber

Beilstein J. Org. Chem. 2025, 21, 1645–1647, doi:10.3762/bjoc.21.128

• impact of [Ru(bpy)3]Cl2 on several research areas, including solar energy conversion [5], optosensing [6], photodynamic therapy [7][8] and bioimaging [9]. Scattered examples of [Ru(bpy)3]Cl2 being used as a photocatalyst for visible-light-driven organic synthesis appeared in the scientific literature as

• implement. Two decades later, photocatalysis and photochemistry remain among the most studied topics in modern organic synthesis. Nowadays, chemists can choose from a wide range of organometallic [12][13], organic [14][15], or heterogeneous photocatalysts [16][17] to trigger visible-light photoredox

• catalysis, and this arsenal of catalysts is constantly expanding. In this thematic issue, the Dell’Amico group describes the development of a new class of organic donor–acceptor photocatalysts that show promising activity for several transformations [18]. Additionally, Hoffmann and co-workers contributed a

Transition-state aromaticity and its relationship with reactivity in pericyclic reactions

• Israel Fernández

Beilstein J. Org. Chem. 2025, 21, 1613–1626, doi:10.3762/bjoc.21.125

• –ene reaction [58][59] constitutes a fundamental reaction in organic chemistry that has been applied to the synthesis of a number of target molecules owing to its remarkable functional group tolerance [60][61]. Despite that, the main shortcoming of this transformation is its relatively high barrier

• chemistry [91][92][93]. Among the number of dipolarophiles compatible with this [3 + 2]-cycloaddition, phosphaalkynes [94][95][96] and arsaalkynes [97] have been recently used because they allow easy access to novel heterocycles. For instance, when using organic azides as dipoles, the transformation leads

• , very recently it was found that the C≡P moiety, in particular, can be stabilized in the form of a cyaphide ligand bonded to a metal fragment [99][100]. These cyaphide complexes are proven to readily undergo 1,3-dipolar cycloaddition reactions with organic azides [99][100][101], affording novel metal

Synthesis of optically active folded cyclic dimers and trimers

• Ena Kumamoto,
• Kana Ogawa,
• Kazunori Okamoto and
• Yasuhiro Morisaki

Beilstein J. Org. Chem. 2025, 21, 1603–1612, doi:10.3762/bjoc.21.124

• substituent(s) at appropriate position(s) on the benzene rings [8]. Enantiopure planar chiral [2.2]paracyclophanes have been used as chiral auxiliaries and chiral ligands for transition metals in the fields of organic and organometallic chemistry [9][10][11][12][13][14][15][16][17][18][19][20]. In 2012

• , and then H2O was added to the reaction mixture. The organic layer was extracted three times with CH2Cl2, and the combined organic layers were washed with saturated aqueous NaHCO3 and brine. After drying over MgSO4 and filtration, the solvent was removed under reduced pressure. The residue was purified

3-Aryl-2H-azirines as annulation reagents in the Ni(II)-catalyzed synthesis of 1H-benzo[4,5]thieno[3,2-b]pyrroles

• Julia I. Pavlenko,
• Pavel A. Sakharov,
• Anastasiya V. Agafonova,
• Derenik A. Isadzhanyan,
• Alexander F. Khlebnikov and
• Mikhail S. Novikov

Beilstein J. Org. Chem. 2025, 21, 1595–1602, doi:10.3762/bjoc.21.123

• reaction, in which 2H-azirines act as the annulation reagent. Keywords: annulation; azirines; benzothiophenes; indoles; nickel catalysis; Introduction 2H-Azirines represent a valuable class of nitrogen heterocycles that are widely used as versatile building blocks in organic synthesis. In particular, the

pH-Controlled isomerization kinetics of ortho-disubstituted benzamidines: E/Z isomerism and axial chirality

• Ryota Kimura,
• Satoshi Ichikawa and
• Akira Katsuyama

Beilstein J. Org. Chem. 2025, 21, 1568–1576, doi:10.3762/bjoc.21.120

• 060-0812, Japan 10.3762/bjoc.21.120 Abstract pH-Responsive molecular switches and motors are a class of organic molecules whose three-dimensional structure can be changed by acid–base stimuli. To date, pH-responsive molecular switches have been developed using various functional groups, but further

• benzamidine derivatives as a novel pH-responsive molecular switch. Keywords: atropisomer; conformation; isomerization; molecular switch; organobase; Introduction pH-Responsive molecular motors and switches are a class of functional organic molecules capable of reversible structural and electronic changes

Synthesis of an aza[5]helicene-incorporated macrocyclic heteroarene via oxidation of an o-phenylene-pyrrole-thiophene icosamer

• Yusuke Matsuo,
• Aoi Nakagawa,
• Shu Seki and
• Takayuki Tanaka

Beilstein J. Org. Chem. 2025, 21, 1561–1567, doi:10.3762/bjoc.21.119

• and evaporation of the solvent to afford a crude product, which was recrystallized from THF to give 5 in 58% yield. Due to its poor solubility in common organic solvents, the 1H NMR spectrum could only be recorded in DMSO. At room temperature, the 1H NMR spectrum in DMSO-d6 exhibited broad signals in

• common organic solvents. Conclusion A novel o-phenylene-pyrrole-thiophene hybrid macrocycle (icosamer 4) was synthesized via Suzuki–Miyaura cross-coupling and isolated in 6% yield. Oxidation of 4 with PIFA produced a partially fused aza[5]helicene-containing macrocycle 5 in 58% yield, which was also

Facile synthesis of hydantoin/1,2,4-oxadiazoline spiro-compounds via 1,3-dipolar cycloaddition of nitrile oxides to 5-iminohydantoins

• Juliana V. Petrova,
• Varvara T. Tkachenko,
• Victor A. Tafeenko,
• Anna S. Pestretsova,
• Vadim S. Pokrovsky,
• Maxim E. Kukushkin and
• Elena K. Beloglazkina

Beilstein J. Org. Chem. 2025, 21, 1552–1560, doi:10.3762/bjoc.21.118

• Juliana V. Petrova Varvara T. Tkachenko Victor A. Tafeenko Anna S. Pestretsova Vadim S. Pokrovsky Maxim E. Kukushkin Elena K. Beloglazkina Department of Chemistry, M.V. Lomonosov Moscow State University, Leninskie Gory 1-3, 119991, Moscow, Russian Federation Organic Chemistry Department, RUDN

• generated nitrile oxide seems to be less significant. It was found that the low solubility of products containing aromatic substituents in non-polar solvents allows for their isolation by washing the crude reaction mixture with diethyl ether to remove organic impurities and then with water to eliminate

Azide–alkyne cycloaddition (click) reaction in biomass-derived solvent Cyrene^TM under one-pot conditions

• Zoltán Medgyesi and
• László T. Mika

Beilstein J. Org. Chem. 2025, 21, 1544–1551, doi:10.3762/bjoc.21.117

• and atom-economical strategies for efficiently assembling new carbon–carbon [1][2][3] and carbon–heteroatom [4][5][6] bonds. Thus, it has become the most attractive and facile methodology for creating various complex organic molecular structures from the laboratory to the industrial scale. Among these

• been characterized as an ideal solvent for click reactions, the limited solubility of most organic substrates could limit its application. Thus, the transformations of either water-insoluble or solid compounds require a solvent to establish high reaction performance, i.e. homogeneous solutions with low

• viscosity. Accordingly, the CuAAC reactions are usually performed in fossil-based common organic reaction media having high vapor pressure, toxicity, flammability, etc., which could result in several serious environmental concerns. According to the FDA guideline [14], common polar aprotic organic solvents

General method for the synthesis of enaminones via photocatalysis

• Paula Pérez-Ramos,
• Raquel G. Soengas and
• Humberto Rodríguez-Solla

Beilstein J. Org. Chem. 2025, 21, 1535–1543, doi:10.3762/bjoc.21.116

• Paula Perez-Ramos Raquel G. Soengas Humberto Rodriguez-Solla Department of Organic and Inorganic Chemistry, and Instituto Universitario de Química Organometálica Enrique Moles, University of Oviedo, Julián Clavería 8, 33006, Oviedo, Spain 10.3762/bjoc.21.116 Abstract Enaminones are key

• ; enaminones; nickel; photocatalysis; Introduction Enaminones are relevant intermediates in organic chemistry and the pharmaceutical industry [1][2][3][4][5][6]. These enamines have a carbonyl group conjugated to a carbon–carbon double bond, owing its great versatility in organic synthesis to its ability to

• act as both electrophiles and nucleophiles [7]. This makes enaminones very reactive, providing an excellent scaffold for organic synthesis. Thus, enaminones are valuable building blocks in the preparation of several carbocyclic [8][9][10][11], heterocyclic [12][13][14][15][16][17][18] as well as

Calcium waste as a catalyst in the transesterification for demanding esters: scalability perspective

• Anton N. Potorochenko and
• Konstantin S. Rodygin

Beilstein J. Org. Chem. 2025, 21, 1520–1527, doi:10.3762/bjoc.21.114

• Anton N. Potorochenko Konstantin S. Rodygin Institute of Chemistry, Saint Petersburg State University, 7/9 Universitetskaya nab., St. Petersburg, 199034, Russia 10.3762/bjoc.21.114 Abstract Esters are valuable compounds in fine organic synthesis and industry. The significant growth in the demand

• amounts of 1–5 wt %. Keywords: biodiesel; calcium oxide; carbide slag; ester; transesterification; Introduction The ester moiety in molecules is one of the most important functional groups, which is widespread in nature, products of fine organic synthesis, and large-scale chemical manufacturing [1][2][3

• fine organic synthesis. Results and Discussion The carbide slag was prepared by hydrolysis of commercially available calcium carbide (Sigma-Aldrich) and oven dried at 80 °C for 3 hours. The active catalyst CS600 was prepared by calcining the carbide slag at 600 °C for 2 hours. The composition of the

Ambident reactivity of enolizable 5-mercapto-1H-tetrazoles in trapping reactions with in situ-generated thiocarbonyl S-methanides derived from sterically crowded cycloaliphatic thioketones

• Grzegorz Mlostoń,
• Małgorzata Celeda,
• Marcin Palusiak,
• Heinz Heimgartner,
• Marta Denel-Bobrowska and
• Agnieszka B. Olejniczak

Beilstein J. Org. Chem. 2025, 21, 1508–1519, doi:10.3762/bjoc.21.113

• Grzegorz Mloston Malgorzata Celeda Marcin Palusiak Heinz Heimgartner Marta Denel-Bobrowska Agnieszka B. Olejniczak Department of Organic and Applied Chemistry, Faculty of Chemistry, University of Lodz, Tamka 12, 91-403 Łódź, Poland Department of Physical Chemistry, Faculty of Chemistry, University

• of the most important types of organic reactions with key importance for the development of methods of modern organic synthesis [1][2][3]. Therefore, conversions of 1,3-dipoles which cover not only cycloadditions but also annulation and insertion reaction attract great attention worldwide [2][3][4

• but also for the synthesis of sulfur-containing organic compounds in general [2][5][6]. Thiocarbonyl S-methanides 1 belong to the class of so-called S-centered, electron-rich 1,3-dipoles and in numerous studies, thermal decomposition of 1,3,4-thiadiazolines 2, which are easily accessible via [3 + 2

Photoredox-catalyzed arylation of isonitriles by diaryliodonium salts towards benzamides

• Nadezhda M. Metalnikova,
• Nikita S. Antonkin,
• Tuan K. Nguyen,
• Natalia S. Soldatova,
• Alexander V. Nyuchev,
• Mikhail A. Kinzhalov and
• Pavel S. Postnikov

Beilstein J. Org. Chem. 2025, 21, 1480–1488, doi:10.3762/bjoc.21.110

• Petersburg State University, 7–9 Universitetskaya Nab., Saint Petersburg, 199034, Russian Federation Department of Organic Chemistry, Lobachevsky State University of Nizhny Novgorod, Gagarina Avenue 23, Nizhny Novgorod, 603950, Russian Federation 10.3762/bjoc.21.110 Abstract The arylation of isonitriles by

• significant attention within organic and medicinal chemistry. Commonly, amide bonds are formed via the reaction of carboxylic acids or their derivatives with appropriate amines (Scheme 1A) [4]. Although this conventional approach is effective and straightforward, it usually suffers from harsh conditions and

• DIPEA as an organic base but the yield of 2aa was very low and we observed a range of byproducts, mainly amine addition instead of water (see Supporting Information File 1, 2.2 Preliminary and Additional Experiments, Figures S5 and S6). Afterwards, we evaluated the other crucial parameters for

Copper catalysis: a constantly evolving field

• Elena Fernández and
• Jaesook Yun

Beilstein J. Org. Chem. 2025, 21, 1477–1479, doi:10.3762/bjoc.21.109

• straightforward reactions. Complementarily, the Review article by Jang and Kim provides a deep understanding of recent advances in the combination of electrochemistry and copper catalysis for various organic transformations [3]. Their contribution elaborates various C–H functionalizations, olefin additions

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

• , to the best of our knowledge, this study represents one of the few examples of a heterogeneous catalysed copper-mediated C–H amination of benzoxazole. The pursuit for greener methodologies in organic synthesis and transitioning from traditional homogeneous catalysis to the use of heterogeneous

• , and the organic phase was extracted with 3.5 M aqueous ammonia solution (1 × 10 mL) and distilled water (2 × 10 mL). The organic phase was washed with brine, dried over sodium sulphate, and filtered. The solvent was removed under reduced pressure to obtain a pure product. Where required, the residue

• h, and the catalyst was then removed by filtration and recovered where required. The solvent was evaporated under reduced pressure. The resulting residue was dissolved in 10 mL of CHCl3, and the organic phase was extracted with distilled water (2 × 10 mL). The organic phase was washed with brine

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

• applications in asymmetric catalysis [1][2], molecular recognition [3], and organic electronics [4][5]. In recent years, the incorporation of heteroatoms – particularly nitrogen – into the helicene backbone, giving rise to so-called "azahelicenes", has emerged as a powerful strategy to modulate electronic

• in applications such as organic light-emitting diodes (OLEDs) [8], circularly polarized luminescence (CPL) [9], and chiral photocatalysis [10]. In the past decade, heteroatom-containing helicenes have attracted increasing attention due to their tunable optoelectronic properties and potential

• polarized organic light-emitting diodes (CP-OLEDs) based on 40 demonstrated a |gEL| of 2.2 × 10−3, a narrow emission bandwidth (FWHM = 49 nm), and a maximum external quantum efficiency (EQE) of 31.5%, placing it among the highest-performing multiple-resonance-induced thermally activated delayed fluorescence

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

• Lidia Zaharieva Vera Deneva Fadhil S. Kamounah Nikolay Vassilev Ivan Angelov Michael Pittelkow Liudmil Antonov Institute of Electronics, Bulgarian Academy of Sciences, 1784 Sofia, Bulgaria Institute of Organic Chemistry with Centre of Phytochemistry, Bulgarian Academy of Sciences, 1113 Sofia

• and systems, including gels [17], metal-organic frameworks [18][19][20][21], photocatalysts [22][23], container molecules [24][25][26], drug delivery systems [27][28][29], photoresponsive polymers [30][31][32][33][34][35][36][37], photoswitches [12][13][38][39][40][41], optical storage devices [42][43

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

• Vladimir G. Ilkin Pavel S. Silaichev Valeriy O. Filimonov Tetyana V. Beryozkina Margarita D. Likhacheva Pavel A. Slepukhin Wim Dehaen Vasiliy A. Bakulev TOS Department, Ural Federal University, 19 Mira str., Yekaterinburg 620002, Russia Department of Organic Chemistry, Perm State University, 15

• Bukireva str., Perm 614990, Russia Department of Organic & Biomolecular Chemistry, Ural Federal University, 19 Mira str., Yekaterinburg 620002, Russia Postovsky Institute of Organic Synthesis, Ural Branch of Russian Academy of Sciences, 22/20 S. Kovalevskoy str., Yekaterinburg 620108, Russia Sustainable