Experimental and DFT studies on the regioselective methanolysis of 5-azido-9-oxabicyclo[6.1.0]nonan-4-yl 4-nitrobenzoate isomers

• İlknur Polat,
• Selçuk Eşsiz and
• Emine Salamci

Beilstein J. Org. Chem. 2026, 22, 547–556, doi:10.3762/bjoc.22.40

• process, highlighting its precision and efficiency. Keywords: azides; 8-azidocyclooct-4-en-1-yl 4-nitrobenzoate; DFT; epoxycyclooctane azide; methanolysis; Introduction Organic azides are very important precursors for the preparation and synthesis of various nitrogen-containing compounds, as well as

• methodologies for the preparation of this class of compounds are of considerable interest. Azides have traditionally been used as protected primary amine equivalents. Therefore, in our previous studies, we employed azides containing eight-membered rings as precursors in the synthesis of C8-aminocyclitols [12

• ][13][14][15][16][17][18][19]. The ring-opening reactions of bicyclic epoxides are of significant importance and scientific interest due to their high ring strain, their strategic role in the construction of complex molecular architectures, and their utility in the synthesis of natural products

Melifoliox B, a novel phloroglucin derivative isolated from Melicope barbigera (Rutaceae) and synthesis of new oxidation products from melifoliones A and B

• Horst Weber,
• Kim-Thao Tran-Cong,
• Bernhard Mayer,
• Guido J. Reiss,
• Iryna S. Konovalova,
• Marc S. Appelhans,
• Kenneth R. Wood and
• Claus M. Passreiter

Beilstein J. Org. Chem. 2026, 22, 535–546, doi:10.3762/bjoc.22.39

• synthesis of 4 and its possible isomer 3, the required compounds 1 and 2 were synthesized as a mixture of the isomers starting from chromene 5, briefly heated in a closed microwave apparatus with catalytic amounts of acetic acid. Forced heating of 5 in acetic acid or use of stronger acids lead to the

• diacetate (EDDA). However, synthesis of 2 was difficult. Despite numerous attempts, we only were able to get mixtures of both melifoliones with minor amounts of 2. Since all attempts to separate both isomers on a preparative scale failed, we were only able to record NMR spectra from a very small quantity of

• -position in regard to the OH-group at C-10b (Table 2). Synthesis of melifoliones Melifolione A (1) was prepared according to the method of Wang and Lee [5] by heating phloroacetophenone and citral with ethylene-diammonium diacetate (EDDA) in DMF. However, reaction of the educts in pyridine at 60 °C led to

Get a better glimpse on sequential photoreactions of trisnorbornadienes with ¹⁹F NMR spectroscopy

• Julian Felix Maria Hebborn,
• Ben Eric Merten,
• Thomas Paululat and
• Heiko Ihmels

Beilstein J. Org. Chem. 2026, 22, 527–534, doi:10.3762/bjoc.22.38

• comparison of the synthesis and photophysical properties of the fluoro-substituted norbornadiene 1f with the ones of the parent compound 1b revealed that the yield of the Suzuki–Miyaura coupling reaction is significantly lower for the former [22], presumably because of the steric hindrance induced by the

• 19F NMR spectroscopy, further structural optimization is necessary for application purposes. Experimental Synthesis 1,3,5-Tris(bicyclo[2.2.1]hepta-2,5-dien-2-yl)-2,4,6-trifluorobenzene (1f) A mixture of 1,3,5-tribromo-2,4,6-trifluorobenzene (212 mg, 575 µmol), 4,4,5,5-tetramethyl-2-(bicyclo[2.2.1

• cycloreversion of 2a. Synthesis and photochromic reaction of trisnorbornadiene 1f to the trisquadricyclane 2f0,3 (numbering of quadricyclanes 2fm,n: m = number of norbornadiene units, n = number of quadricyclane units). Stepwise photoreaction of 1f to 2f0,3 (numbering of quadricyclanes 2fm,n: m = number of

Modern synthetic pathways towards eribulin and its subunits

• Sebastian Dominik Graf

Beilstein J. Org. Chem. 2026, 22, 495–526, doi:10.3762/bjoc.22.37

• approaches is rigorously ongoing. Recent procedures mainly focus on more efficient and scalable techniques for the assembly of the 4 key fragments of eribulin. But also new pathways for the total synthesis have emerged in the last decade. In this review the latest advancements towards the construction of

• eribulin are summarized. Keywords: breast cancer; drug manufacturing; eribulin; Halaven; total synthesis; Introduction Eribulin (1) is a truncated derivative of halichondrin B (2), a complex natural product originally isolated from the marine sponge Halichondria okadai (Figure 1) [1][2][3][4][5]. Already

• described the total synthesis of the marine natural product [19] and shortly thereafter, also its simplified structure, 1, was assembled and showed similar anticancer behavior [19][21]. Since 2010, the mesylate salt of 1 is approved by the U.S. Food and Drug Administration (FDA) for the treatment of

Synthesis and uranyl(VI) extraction performance of a calix[4]pyrrole–tetrahydroxamic acid receptor

• Sara Karnib,
• Rana Baydoun,
• Wissam Zaidan,
• Nancy AlHaddad,
• Omar El Samad,
• Bilal Nsouli,
• Francine Cazier-Dennin and
• Pierre-Edouard Danjou

Beilstein J. Org. Chem. 2026, 22, 486–494, doi:10.3762/bjoc.22.36

• extractants. Here, we report the design and synthesis of PCP HA, a phenoxycalix[4]pyrrole scaffold functionalized with four hydroxamic acid (HA) groups, and evaluate its uranium(VI) extraction potential. PCP HA was synthesized from its ester precursor (PCP E) via hydroxyaminolysis using KOH, achieving a 95

• capable of remediating uranium from aqueous environments [38][39]. Results and Discussion PCP HA synthesis and characterization Various strategies have been developed for the synthesis of hydroxamic acid derivatives over the years [40]. Classical and most popular routes involve the direct reaction of

• aldehydes [45], alcohols [46], and amides [47] have also been reported. However, the literature states that there is no particular reagent or reaction condition that can serve as a general rule for the synthesis of hydroxamic acids [48]. In this study, the direct reaction of hydroxylamine with the PCP ester

Synthesis of a HDAC inhibitor–nanogold probe for cryo-EM visualization in class I HDAC co-repressor complexes

• Wiktoria A. Pytel,
• John W. R. Schwabe and
• James T. Hodgkinson

Beilstein J. Org. Chem. 2026, 22, 480–485, doi:10.3762/bjoc.22.35

• LE1 7RH, UK 10.3762/bjoc.22.35 Abstract Class I histone deacetylases (HDACs 1–3) serve as catalytic subunits within seven multiprotein co-repressor complexes, each of which has distinct functions in the cell. We report the synthesis of a HDAC inhibitor–nanogold probe, derived from the class I HDAC

• synthesize a nanogold-conjugated HDAC inhibitor and evaluate its applicability in single-particle cryo-EM to unambiguously determine the positioning and orientation of the HDAC active site within the CoREST complex. Results and Discussion Design and synthesis of a HDAC inhibitor–nanogold probe For the basis

• routes (Scheme 1) [14][15][18]. Intermediates 5–7 were prepared in a manner analogous to Smalley et al. [14]. The first step in the linker synthesis for Au–(CI-994) involved a monoprotection of nonanedioic acid with a benzyl group to give 5 which proceeded in moderate yield due to the formation of the

Recent advances in the stereoselective synthesis of distal biaxially chiral molecules

• Fanxing Zhou,
• Chen Zhang,
• Lingyu Sun,
• Yiyun Fang,
• Siming Zheng,
• Lina Hu,
• Mengyang Shen,
• Zhen Zhao,
• Wei Xu,
• Yunqiang Sun and
• Zi-Qiang Rong

Beilstein J. Org. Chem. 2026, 22, 461–479, doi:10.3762/bjoc.22.34

• distal axial chiralities are widely applied in chiral ligands, natural products, and anticancer agents, with their unique spatial configurations endowing them with distinctive functions and values. Although significant progress has been made in the asymmetric synthesis of distal biaxial chirality

• biaxial chirality, multistep sequential generation, and conversion from central to biaxial chirality, with the aim of providing new perspectives and methodologies for further development in this area. Keywords: axially chiral compounds; stereoselective synthesis; Introduction In recent years, axially

• "-ternaphthalene compounds [35]. This work significantly advanced the development of bi- and multiaxial chirality. The synthesis of multiaxial chiral molecules requires appropriate steric hindrance to elevate the rotational energy barrier of each chiral axis [36], and the spatial interactions between axes are

Structural reassignment of compound 968, an allosteric glutaminase inhibitor

• Lindsey A. Albertelli,
• Sainabou Jallow,
• Chun Li and
• Scott M. Ulrich

Beilstein J. Org. Chem. 2026, 22, 455–460, doi:10.3762/bjoc.22.33

• isomer 2 in agreement with the reports of Martinez and Koslov. Since the only reaction reported to give the benzo[c]phenanthridine isomer 1 is the three-component reaction that instead produces the isomeric benzo[c]acridine 2, we believe that the synthesis of benzo[c]phenanthridine isomer 1 remains

• diffractometer. Nuclear magnetic resonance spectra were recorded on a JEOL ECX400 spectrometer. Glutaminase assays were measured on a Tecan Infinite M nano spectrophotometer. Reagents and solvents for chemical synthesis were used without additional purification. Chemical synthesis 3-Bromo-4

Concept-driven strategies in target-oriented synthesis

• David Yu-Kai Chen,
• Chao Li and
• Yefeng Tang

Beilstein J. Org. Chem. 2026, 22, 451–454, doi:10.3762/bjoc.22.32

• history of science. Indeed, organic compounds have an unparalleled track record in elucidating the mysteries behind a wide range of physical, chemical, and biological phenomena, and advances in chemical synthesis have been instrumental in these explorations. Specifically, target-oriented syntheses of

• advancements, and strategic innovations. However, while efficiency and practicality remain essential design considerations in targeted synthesis, it is worth pondering whether the pursuit of efficiency (along with its associated elements) truly captures the underlying scientific essence of target-oriented

• synthesis. It is widely acknowledged that the initial allure of target-oriented synthesis often arose from the intellectually and aesthetically captivating strategies involved, with the mastery of synthetic design best exemplified through the perplexing structural relationships between target molecules and

A facile and practical method for the synthesis of trans-(±)-taxifolin and its derivatives via Darzens reaction

• Bo Peng,
• Panpan Yang,
• Maaz Khan,
• Xiaotong Lin,
• Jiang Wu,
• Peng Fu and
• Qingqing Wu

Beilstein J. Org. Chem. 2026, 22, 443–450, doi:10.3762/bjoc.22.31

• Pharmacy, Shenzhen Technology University, Shenzhen 518118, China 10.3762/bjoc.22.31 Abstract The synthesis of racemic trans-taxifolin (trans-(±)-taxifolin) and its derivatives and subsequent chiral separation is the most prevalent chemical method to obtain enantiomerically pure taxifolin and its

• yields (20–41%) and proceeds without the use of explosive peroxides (such as H2O2), which are commonly employed in methods reported earlier. The avoidance of explosive peroxides in the present method enables safe operation, easy scale-up, and also the synthesis of taxifolin derivatives with oxidant

• -sensitive groups, largely expanding the substituent scope compared with the previous method. Keywords: Darzens reaction; derivatives; scale-up; synthesis; taxifolin; Introduction Taxifolin is a sub-member of the flavonoid family with outstanding bioactive performance [1]. Several in vitro and in vivo

Synthesis and stereochemical analysis of dynamic planar chiral oxa[7]orthocyclophene

• Yukiho Hashimoto,
• Yuuya Kawasaki,
• Kazunobu Igawa and
• Katsuhiko Tomooka

Beilstein J. Org. Chem. 2026, 22, 436–442, doi:10.3762/bjoc.22.30

• oxacyclophene enabled the efficient and divergent synthesis of C6-substituted derivatives. The stereochemical analysis of the oxacyclophenes revealed that the iodo- and methyl-substituted derivatives have reasonable stereochemical stability. The planar chirality of the methyl-substituted oxacyclophene was

• -substituted oxacyclophenes 1ab (X = O, Y = Me), 1ac (X = O, Y = Ph), and 1ad (X = O, Y = I), in which 1ad was used as the key intermediate for the synthesis of 1ab and 1ac via Kumada–Tamao coupling with Grignard reagents (Figure 2). Results and Discussion Retrosynthesis and synthesis of the C6-iodo

• of propargyl alcohol 3 and the alkyne moiety in 3 can be introduced by an alkynylation of the formyl group of aldehyde 4. Thus, we started this synthesis from O-protected 2-bromobenzyl alcohol derivative 5 for the introduction of the propanal moiety of 4 by a Heck reaction with allyl alcohol. The

Synthesis and anti-cancer activity of naphthalimide–organylselanyl conjugates

• Rajkumar Ravi and
• Selvakumar Karuthapandi

Beilstein J. Org. Chem. 2026, 22, 416–435, doi:10.3762/bjoc.22.29

• naphthalimide has also been explored to a considerable extent [45][46]. In general, the tert-butyl group has attracted considerable attention in drug design and synthesis due to its lipophilic character [47][48]. From the above-mentioned point of view, we have changed both sides of the substitution with a new

• Discussion Chemistry Scheme 1 illustrates the synthesis of naphthalimide-organylselanyl conjugates 7 and 8. The incorporation of the organoselenide moiety into the naphthalimide scaffold was achieved via a nucleophilic substitution reaction. The bromine atom in the bromonaphthalimide precursor 12, prepared

• compounds, making it a viable alternative for introducing long alkyl chains into selenium-containing systems towards lysosomal membrane permeability (vide supra) [42][43][44]. After synthesis, compounds 7 and 8 were thoroughly characterised using multinuclear NMR spectroscopy ¹H, ¹³C, and ⁷⁷Se NMR

Cone p-aminocalix[4]arenes enriched with ‘clickable’ alkyne or azide functionalities

• Ilia Korniltsev,
• Vasily Bazhenov,
• Alexander Gorbunov,
• Dmitry Cheshkov,
• Stanislav Bezzubov,
• Vladimir Kovalev and
• Ivan Vatsouro

Beilstein J. Org. Chem. 2026, 22, 399–415, doi:10.3762/bjoc.22.28

• Compounds, Sh. Entuziastov 38, 105118 Moscow, Russia Kurnakov Institute of General and Inorganic Chemistry, Russian Academy of Sciences, Leninskii pr. 31, 119991 Moscow, Russia 10.3762/bjoc.22.28 Abstract Efficient approaches have been developed for the synthesis of heteromultifunctional cone calix[4

• thermodynamic and kinetic stability of the capsules and the guest exchange processes [55][56][57][58][59][60]. This has made dimerization of tetraureacalix[4]arenes one of the most explored self-organization processes in calixarene supramolecular chemistry, which has been used in the template synthesis of

• herein report on the synthesis approaches to a series of cone p-aminocalix[4]arenes having propargyl or 2-azidoethyl groups at the narrow rims (Figure 1). The newly synthesized compounds may be thus treated as novel building blocks in calixarene chemistry capable of step-wise orthogonal transformations

Design, synthesis and biological evaluation of 2,5-diaryloxazolo[4,5-d]pyrimidin-7-ylamines as selective cytotoxic agents against HeLa cells

• Maryna V. Kachaeva,
• Agnieszka B. Olejniczak,
• Marta Denel-Bobrowska,
• Victor V. Zhirnov,
• Yevheniia S. Velihina,
• Stepan G. Pilyo and
• Volodymyr S. Brovarets

Beilstein J. Org. Chem. 2026, 22, 390–398, doi:10.3762/bjoc.22.27

• lines such as HepG2 (liver), HeLa (cervix), A549 (lung), and glioblastoma models rely on enhanced nucleotide metabolism to sustain rapid DNA/RNA synthesis. Oxazolopyrimidines can inhibit these overactive enzymes in cancer cells, while normal cells (with lower demand) are less affected. This explains why

• potential. Therefore, further functionalization of 2,4-diaryl[1,3]oxazolo[4,5-d]pyrimidines at position 7 of the structure-forming core was carried out in this work. Results and Discussion Chemistry The synthesis of 1,3-oxazolo[4,5-d]pyrimidine derivatives 1–9 was accomplished according to the previously

• ][1,5]diazocin-8-one) are commercially available reagents from Sigma-Aldrich. Aminoethylamines were synthesized according to the literature method [16] and used as racemic mixtures. General procedure for the synthesis of oxazolo[4,5-d]pyrimidines 1–9 A solution of 0.01 mol of the corresponding 7

Dialkylaminoalkylation of β-ketosulfones via ring-opening of 3-sulfonylpyrrolidines

• Evgeny M. Buev,
• Alexander V. Pavlushin,
• Vladimir S. Moshkin and
• Vyacheslav Y. Sosnovskikh

Beilstein J. Org. Chem. 2026, 22, 383–389, doi:10.3762/bjoc.22.26

• antiandrogen cancer treatment [8][9] (Figure 1). Moreover, aminosulfones remain a privileged scaffold in the ongoing development of new methods for the synthesis of pharmaceuticals [10][11][12], with multiple research compounds showing promising bioactivities such as MMP inhibition [13], antiinflammatory

• effects [14], сoagulation enzyme factor (FXa) inhibition [15] and antidepressant properties [16]. Considering the approaches to the synthesis of γ-aminosulfones, we focused our attention on the implementation of an aminoalkylation as a powerful and versatile tool for the synthesis of aliphatic amines [17

• commonly achieved by a classic nucleophilic substitution of a leaving group at the β-position relative to the N-protected nitrogen (Figure 2a). While this approach addresses most needs of targeted synthesis, developing alternative methods from inexpensive starting materials via domino-processes, allowing

Electrosynthetic access to unsymmetrical oxaza[8]helicenes with high chiral stability and strong circularly polarized luminescence (CPL)

• Tin Zar Aye,
• Rubal Sharma,
• Muthu Karuppasamy,
• Daiya Suzuki,
• Haruka Nakajima,
• Yoshitane Imai,
• Mitsuhiro Arisawa,
• Mohamed S. H. Salem and
• Shinobu Takizawa

Beilstein J. Org. Chem. 2026, 22, 372–382, doi:10.3762/bjoc.22.25

• Heterohelicenes are compelling chiral π-conjugated scaffolds for optoelectronic and chiral-photonic technologies because their helical frameworks and doped heteroatoms endow them with various photophysical, chiroptical, and electronic merits. However, unsymmetrical heterohelicenes remain rare, as their synthesis

• unsymmetrical oxaza[8]helicenes Building on Zhang’s facile acid-mediated carbazole synthesis [53], in which aniline derivatives react with p-benzoquinone to afford 3-hydroxycarbazoles [54], we employed a closely related substrate. Specifically, N-(p-tolyl)phenanthren-3-amine (2) – prepared from 3

• dashed lines for (P)-configuration of 5a (black), 5b (blue), 6a (green), and 6b (red). Recent examples of hetero[8]helicenes: (A) symmetric hetero[8]helicenes; (B) unsymmetrical hetero[8]helicenes; (C) short-step electrosynthetic access to new unsymmetrical oxaza[8]helicenes. Short-step synthesis of

Non-central chirality in organic chemistry

• Ken Tanaka and
• Naohiko Yoshikai

Beilstein J. Org. Chem. 2026, 22, 370–371, doi:10.3762/bjoc.22.24

• Ken Tanaka Naohiko Yoshikai Department of Chemical Science and Engineering, Institute of Science Tokyo, O-okayama, Meguro-ku, Tokyo 152-8550, Japan Graduate School of Pharmaceutical Sciences, Tohoku University, Aoba-ku, Sendai 980-8578, Japan 10.3762/bjoc.22.24 Keywords: asymmetric synthesis

• complementary roles played by non-central chiral molecules in contemporary organic chemistry. First, they continue to serve as demanding benchmarks for asymmetric synthesis, probing how far stereochemical information can be transmitted and controlled when the stereogenic element is spatially or conceptually

Recent advances in the cleavage of non-activated amides

• Eun-Sol Choi and
• Hyo-Jun Lee

Beilstein J. Org. Chem. 2026, 22, 352–369, doi:10.3762/bjoc.22.23

• twisted amides have revolutionized amide-bond activation, their preparation often requires multistep synthesis or the installation of strongly electron-withdrawing groups, thereby limiting their broad applicability. Thus, the selective activation and transformation of non-twisted, non-activated amides

• substitution, making its selective transformation a long-standing challenge in organic synthesis. While strategies for activating twisted amides, bearing electron-withdrawing and sterically demanding substituents on nitrogen, are now well established, general and efficient methods for modifying conventional

• for activation of non-activated amides. Esterification of amides catalyzed by CeO2. Hydrolysis of amides catalyzed by Nb2O5. Manganese-catalyzed esterification of tertiary amides. Tungsten-catalyzed transamidation of hindered tertiary amides. Palladium-catalyzed transamidation of amides. Synthesis of

Synthesis of tricyclic fused pyrrolidine nitroxides from 2-alkynylpyrrolidine-1-oxyls

• Mark M. Gulman,
• Yuliya F. Polienko,
• Sofia Yu. Trakhininа,
• Yuri V. Gatilov,
• Tatyana V. Rybalova,
• Sergey A. Dobrynin and
• Igor A. Kirilyuk

Beilstein J. Org. Chem. 2026, 22, 344–351, doi:10.3762/bjoc.22.22

• framework is impossible is one of the ways to improve properties of ORCA. Feasibility of the synthesis of rigid 3b,4,5,6,6a,7-hexahydropyrrolo[2',3':3,4]pyrrolo[1,2-c][1,2,3]triazole and 3b,4,5,6,6a,7-hexahydropyrrolo[2',3':3,4]pyrrolo[1,2-b]pyrazole ring systems with incorporated nitroxide moiety from 2

• -2-ethynylpyrrolidine-1-oxyls with nucleophilic agents can lead to the formation of condensed systems involving the substituent at position 3 of the pyrrolidine ring [16]. Alkynes are broadly used in the synthesis of various heterocyclic compounds, and participation of neighboring functional groups

• Huisgen cycloaddition or via one-pot Michael addition–cyclocondensation reaction with hydrazine with subsequent intramolecular alkylation of the resulting pyrazoles. Results and Discussion Synthesis We have earlier reported on the synthesis of 2-alkynylpyrrolidine-1-oxyls 2a–c via addition of the

Ring contraction and ring expansion reactions in terpenoid biosynthesis and their application to total synthesis

• Nicolas Kratena,
• Nicolas Heinzig and
• Peter Gärtner

Beilstein J. Org. Chem. 2026, 22, 289–343, doi:10.3762/bjoc.22.21

• . This review aims to explore intriguing examples of such ring-size alterations in all aspects of terpenoid synthesis. The current state-of-the-art regarding proposed biosynthetic pathways for terpenoids with unusual carbon skeleta, occurring either during initial cyclisation or subsequent oxidative

• editing; terpenoids; total synthesis; Introduction The vast richness of structural diversity in terpenoid natural products has fascinated organic chemists for more than a century now [1][2][3][4][5]. With more sophisticated techniques for isolation and characterisation emerging over the decades

• secured. Organic synthetic chemistry can help to fill gaps or evaluate, support or revise initially implausible proposed biogenesis routes by attempting to mimic these transformations (= bioinspired or biomimetic synthesis) [11][12][13][14][15][16][17][18]. In general, the biogenesis of unique carbon

Spirobarbiturates with a pyrrolizidine moiety: synthesis, structure and biological evaluation

• Arthur A. Puzyrkov,
• Andrew S. Drachuk,
• Ekaterina A. Popova,
• Alexander V. Stepakov and
• Vitali M. Boitsov

Beilstein J. Org. Chem. 2026, 22, 274–288, doi:10.3762/bjoc.22.20

• 21st century, this research culminated in the approval of the first drug whose active molecule contained a spirobarbiturate scaffold – zoliflodacin© (Scheme 1) [7]. Due to the significance of spirobarbiturates, numerous approaches have been devised for their synthesis [13][14][15][16][17][18][19

• ]. Advances in this area of organic synthesis include the preparation of barbiturates containing spiro-fused cyclohexane, cyclopentane, tetrahydrooxepine, and tetrahydroquinoline moieties via [3 + 2], [4 + 2], and [5 + 2] annulation reactions involving arylidene and alkylidene barbiturates [20][21][22][23

• barbiturates [25]. Other methods include the DBU-mediated stereospecific cyclopropanation of barbiturate-based olefins with benzyl chlorides, developed by Chang’s group for the synthesis of spirobarbiturate-cyclopropanes [26]. Another interesting structural fragment is the pyrrolizidine heterocycle, which is a

Arene activation via π-bond localization: concepts and opportunities

• Paul Meiners,
• Julian J. Melder and
• Tobias Morack

Beilstein J. Org. Chem. 2026, 22, 257–273, doi:10.3762/bjoc.22.19

• transformations for the synthesis of complex, three-dimensional molecular architectures with tailored physicochemical properties. Despite notable advances in dearomative methodologies over the past decades, the selective and controlled disruption of the aromatic core continues to represent a fundamental challenge

• as well as transition metal coordination to aromatic fragments in an η2-, η3-, and η4-fashion. The structural and reactivity consequences of these perturbations are analyzed in detail, and representative examples of stoichiometric and, where available, catalytic applications in synthesis are

• exposure to reaction conditions that more labile systems could not tolerate. Crucially, most reagents used in organic synthesis react preferentially with the arene ligand rather than the metal center [45]. Building on the electronic blueprint established by the osmium system, Harman introduced a new

A mild and atom-efficient four-component cascade strategy for the construction of biologically relevant 4-hydroxyquinolin-2(1H)-one derivatives

• Dmitrii A. Grishin,
• Kseniia I. Sharkovskaia,
• Ilya G. Kolmakov,
• Daria A. Ipatova,
• Rostislav A. Petrov,
• Nikolai D. Dagaev,
• Dmitry A. Skvortsov,
• Maria G. Khrenova,
• Valeriy V. Andreychev,
• Sergei A. Evteev,
• Yan A. Ivanenkov,
• Roman L. Antipin,
• Olga А. Dontsova and
• Elena K. Beloglazkina

Beilstein J. Org. Chem. 2026, 22, 244–256, doi:10.3762/bjoc.22.18

• and selective synthesis of previously inaccessible 4-hydroxyquinolin-2(1H)-one derivatives. Utilizing readily available 6-halo-4-hydroxyquinolinones, aromatic aldehydes, Meldrum’s acid, and alcohols under ʟ-proline catalysis, the reaction proceeds via in situ formation of arylidene-substituted Meldrum

• , offering high atom economy, operational simplicity, and remarkable versatility [9][10][11][12][13]. Owing to their flexibility in combining diverse building blocks, MCRs have found widespread application in the synthesis of biologically active compounds. This versatility significantly shortens synthetic

• against Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa [34]. The diversity of pharmacological activities renders 4-hydroxyquinoline-2(1H)-one derivatives highly valuable targets in medicinal chemistry, driving continued interest in their synthesis and exploration [23]. However, the

Configuration–packing synergy enabling integrated crystalline-state RTP and amorphous-state TADF

• Ruiyan Wang and
• Yunan Wu

Beilstein J. Org. Chem. 2026, 22, 224–236, doi:10.3762/bjoc.22.16

• EL spectra were measured under ambient conditions. Synthesis The synthetic route to 1 is shown in Scheme 1 and comprises imide formation followed by a Suzuki–Miyaura cross coupling. Synthesis of 5-bromo-2-(p-tolyl)isoindoline-1,3-dione (PI-Br, 4) In the first step, 2 (2.00 g, 8.81 mmol) was carefully

• dried crude product was purified by column chromatography using a solvent mixture of dichloromethane and n-hexane in a 1:2 volume ratio. The purified product 4 was obtained as a white solid in a yield of 2.53 g (91%). Synthesis of 5-(3-(9H-carbazol-9-yl)phenyl)-2-(p-tolyl)isoindoline-1,3-dione (1) For

• the synthesis of compound 1, 5-bromo-2-(p-tolyl)isoindoline-1,3-dione (4, 1.00 g, 3.16 mmol) was first dissolved in 80 mL of tetrahydrofuran (THF) in a 250 mL three-necked round-bottomed flask. The solution was again purged with nitrogen gas for 30 minutes to create an inert atmosphere and ensure that

Synthesis of diaryl phosphates using phytic acid as a phosphorus source

• Kazuya Asao,
• Seika Matsumoto,
• Haruka Mori,
• Riku Yoshimura,
• Takeshi Sasaki,
• Naoya Hirata,
• Yasuyuki Hayakawa and
• Shin-ichi Kawaguchi

Beilstein J. Org. Chem. 2026, 22, 213–223, doi:10.3762/bjoc.22.15

• soil. It can potentially serve as a phosphorus source in the syntheses of organic phosphates; however, this approach has not been utilized for the preparation of phosphate esters. In this study, we report the first successful synthesis of phosphate esters using phytic acid as a phosphorus source. Crude

• rely on phosphate rock but instead uses biomass as a phosphorus source. Keywords: diaryl phosphates; phosphate esters; phosphate ester synthesis; phosphorus recovery; phytic acid; Introduction Phytic acid (myo-inositol-1,2,3,4,5,6-hexakisphosphate, Scheme 1) is a phosphorus-rich molecule, which is

• -free synthetic methods have been reported for the synthesis of phosphorus compounds (Figure 2A) [35][36][37][38][39][40][41]. Cummins’s group demonstrated that phosphoric acid and condensed phosphoric acid can be reduced using trichlorosilane. The resulting intermediate, the bis(trichlorosilyl