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

Recent total synthesis of natural products leveraging a strategy of enamide cyclization

• Chun-Yu Mi,
• Jia-Yuan Zhai and
• Xiao-Ming Zhang

Beilstein J. Org. Chem. 2025, 21, 999–1009, doi:10.3762/bjoc.21.81

• . Optimization studies identified the tetraphenyl-substituted PyBox ligand L1 as particularly effective in controlling the stereochemistry of the polycyclization, yielding high enantioselectivity for most substrates. As illustrated in Scheme 5, tertiary enamides with a tethered electron-rich arene could undergo

• attack of the electron-rich arene on the acyliminium ion occurs from the Si-face. This stereochemical outcome is attributed to the steric discrepancy of the phenyl or tert-butyl group and the hydroxy group. The resulting tricyclic products could be further elaborated by elimination or amide reduction to

• diastereo- and enantioselectivities. The substituent on the enamide could be varied from aryl to tert-butyl groups, though the terminating aryl group still necessitates an electron-rich arene. As was found in their previous work, the steric hindrance of the phenyl or tert-butyl group was supposed to be

On the photoluminescence in triarylmethyl-centered mono-, di-, and multiradicals

• Daniel Straub,
• Markus Gross,
• Mona E. Arnold,
• Julia Zolg and
• Alexander J. C. Kuehne

Beilstein J. Org. Chem. 2025, 21, 964–998, doi:10.3762/bjoc.21.80

Dicarboxylate recognition based on ultracycle hosts through cooperative hydrogen bonding and anion–π interactions

• Wen-Hui Mi,
• Teng-Yu Huang,
• Xu-Dong Wang,
• Yu-Fei Ao,
• Qi-Qiang Wang and
• De-Xian Wang

Beilstein J. Org. Chem. 2025, 21, 884–889, doi:10.3762/bjoc.21.72

• , we report the design of ultracycles constructed from functional tetraoxacalix[2]arene[2]triazine submacrocycles. These submacrocycles feature hydroxy groups as hydrogen-bonding (HB) donors on the lower rim, which, in combination with electron-deficient triazines, create cooperative HB and anion–π

• ) solution of the compound at 4 °C, enabling structural analysis of the ultracycle. As illustrated in Figure 1, the backbone of B4aH adopts a Z-like shape with a flexible conformation. The two oxacalix[2]arene[2]triazine subcavities are positioned along the short axis in a staggered face-to-face arrangement

Recent advances in the electrochemical synthesis of organophosphorus compounds

• Babak Kaboudin,
• Milad Behroozi,
• Sepideh Sadighi and
• Fatemeh Asgharzadeh

Beilstein J. Org. Chem. 2025, 21, 770–797, doi:10.3762/bjoc.21.61

• arylphosphonates via carbon–phosphorus bond formation. In 2021, Xu et al. [52] reported an electrochemical process for synthesizing arylphosphonates through the hetero-coupling reaction of CH of arenes with a trialkyl phosphite. They have prepared 45 arene phosphonates with good to excellent yields and reported

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

• Keith G. Andrews

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

• versions. Recent advances using hexameric resorcin[4]arene-based capsules [122][123][124] (Figure 4B and C), notably by Tiefenbacher [105][125][126][127][128][129][130][131][132][133], have demonstrated substrate-controlled selectivities that vary from the bulk phase due to the stabilization of cations in

• instance, the window[1]resorcin[3]arene capsule type [135] demonstrates that the symmetry and properties of traditional symmetric capsules can be modulated, although precise control over the assembly remains difficult. Finally, we must mention the recently reported cavitand capsules of Gibb, who has

• ) Self-assembling capsules can perform hydrophobic catalysis [116][117]. (B) Resorcin[4]arene building block. (C) Hexameric resorcin[4]arene-based capsules [122] include structural water. The cavity can stabilize cations (substrates or transition states) and perform catalysis using dual activation of a

Recent advances in electrochemical copper catalysis for modern organic synthesis

• Yemin Kim and
• Won Jun Jang

Beilstein J. Org. Chem. 2025, 21, 155–178, doi:10.3762/bjoc.21.9

• elimination, produces C–H alkynylated arene 10, which then forms the final product 3 through intramolecular cyclization. Finally, the Cu(I) complex 9 produced via reductive elimination is reoxidized at the anode to regenerate the Cu(II) complex 4, completing the catalytic cycle. Yao and Shi developed the

Cu(OTf)₂-catalyzed multicomponent reactions

• Sara Colombo,
• Camilla Loro,
• Egle M. Beccalli,
• Gianluigi Broggini and
• Marta Papis

Beilstein J. Org. Chem. 2025, 21, 122–145, doi:10.3762/bjoc.21.7

• -difunctionalization of alkenes carried out with carbazates (N-aminocarbamates) and (hetero)arene nucleophiles or amines exploiting N-(tert-butyl)-N-fluoro-3,5-bis(trifluoromethyl)benzenesulfonamide (NFBS) as intermolecular hydrogen-atom-transfer reagent results in alkylarylation processes (Scheme 5) [19]. The

• involves a Friedel–Crafts alkylation of the arene followed by hydroamination (Scheme 6) [5]. The mechanism plausibly starts with the in situ formation of triflic acid from Cu(OTf)2 which leads to protonation of the oxygen atom of the alcohol with generation of the activated allyl alcohol. This latter gives

• the allyl carbenium ion VI through the loss of a molecule of water, then undergoes a Friedel–Crafts alkylation by attack of the aromatic partner. The outcome of the reaction proceeds through a Markovnikov protonation of the allylated arene VII by triflic acid, which generates the carbocation

Recent advances in organocatalytic atroposelective reactions

• Henrich Szabados and
• Radovan Šebesta

Beilstein J. Org. Chem. 2025, 21, 55–121, doi:10.3762/bjoc.21.6

• process was inspired by the biocatalytic synthesis of aromatic polyketides by polyketide synthase from poly β-carbonyl substrates. Pyrrolidine-based organocatalyst C4 was able to promote a twofold atroposelective arene-forming 6-enolendo aldol condensation (Scheme 4). Sparr also realized a central-to

Synthesis, structure and π-expansion of tris(4,5-dehydro-2,3:6,7-dibenzotropone)

• Yongming Xiong,
• Xue Lin Ma,
• Shilong Su and
• Qian Miao

Beilstein J. Org. Chem. 2025, 21, 1–7, doi:10.3762/bjoc.21.1

• , expanding its π-skeleton through the Barton–Kellogg and Scholl reactions led to the successful synthesis of a curved polycyclic arene containing three heptagons and two pentagons. Keywords: carbon schwarzites; polycyclic arenes; Scholl reaction; seven-membered carbocycle; Yamamoto coupling; Introduction

• synthesis of 1 using a Ni-mediated Yamamoto coupling reaction and the simultaneous crystallization of its two different conformers from the same solution. Expanding the π-skeleton of 1 through a Barton–Kellogg reaction followed by a subsequent Scholl reaction resulted in a new polycyclic arene (3 in Figure

Efficient synthesis of fluorinated triphenylenes with enhanced arene–perfluoroarene interactions in columnar mesophases

• Yang Chen,
• Jiao He,
• Hang Lin,
• Hai-Feng Wang,
• Ping Hu,
• Bi-Qin Wang,
• Ke-Qing Zhao and
• Bertrand Donnio

Beilstein J. Org. Chem. 2024, 20, 3263–3273, doi:10.3762/bjoc.20.270

• -67034 Strasbourg, France 10.3762/bjoc.20.270 Abstract The high potential of non-covalent arene–fluoroarene intermolecular interactions in the design of liquid crystals lies in their ability to strongly promote self-assembly, improve the order and stability of the supramolecular mesophases, and enable

• derivatives and the antiparallel stacking mode into columnar structures stabilized by arene–perfluoroarene intermolecular interactions were confirmed by the single-crystal structure of the alkoxy-free side chain analog, i.e., 1,2,4-trifluoro-3-(perfluorophenyl)triphenylene (F). UV–vis absorption and

• red-shift of the emission peak. Keywords: arene–perfluoroarene interaction; decafluorobiphenyl; fluorinated triphenylene; fluoroarene nucleophilic substitution; organolithium; Introduction Non-covalent arene–fluoroarene intermolecular interactions [1][2] are drawing increasing attention due to their

Direct trifluoroethylation of carbonyl sulfoxonium ylides using hypervalent iodine compounds

• Radell Echemendía,
• Carlee A. Montgomery,
• Fabio Cuzzucoli,
• Antonio C. B. Burtoloso and
• Graham K. Murphy

Beilstein J. Org. Chem. 2024, 20, 3182–3190, doi:10.3762/bjoc.20.263

• % yield, and comparable yields were observed for the p-tolyl and p-chlorophenyl derivatives 3n and 3o. A slight increase in yield was found with the p-anisyl derivative (3p, 61% yield), whereas the yield decreased when the arene was appended with an electron-withdrawing CF3 group (3q, 45% yield). Though

• generated using an isodensity surface of 0.001 a.u. [50]. This showed two sigma holes of different potentials, with the stronger (0.21 e) residing opposite the arene, and the slightly weaker (0.20 e) hole residing opposite the trifluoroethyl motif (Figure 3, left). These sigma-hole potentials are consistent

• arene moieties. These observations confirmed the LUMO as an appropriate lobe for nucleophilic attack via the SN2 pathway (path 2), and confirmed the LUMO+1 as an appropriate lobe for substitution via reductive elimination (path 1). As such, neither mechanism could be immediately discarded, and we were

Hypervalent iodine-mediated intramolecular alkene halocyclisation

• Charu Bansal,
• Oliver Ruggles,
• Albert C. Rowett and
• Alastair J. J. Lennox

Beilstein J. Org. Chem. 2024, 20, 3113–3133, doi:10.3762/bjoc.20.258

• via electrochemical oxidation of 4-iodotoluene at the anode, in a 5:6 HF:amine mixture to cyclise a range of phenolic ethers 33. Tolerance for substituents on both the aromatic ring and the alkene were shown, although the electronic requirements were quite narrow for reaction success. As the arene

Advances in the use of metal-free tetrapyrrolic macrocycles as catalysts

• Mandeep K. Chahal

Beilstein J. Org. Chem. 2024, 20, 3085–3112, doi:10.3762/bjoc.20.257

• used three different types of macrocycles: calix[4]pyrroles 11, 17a–c, porphyrin 18, and calix[4]arene 19 (Figure 4a). Despite the presence of –OH and –NH binding sites, both calix[4]arene 19 and porphyrin 18 showed only a negligible activity compared to calix[4]pyrroles (11, 17a–c), which provided

Extension of the π-system of monoaryl-substituted norbornadienes with acetylene bridges: influence on the photochemical conversion and storage of light energy

• Robin Schulte,
• Dustin Schade,
• Thomas Paululat,
• Till J. B. Zähringer,
• Christoph Kerzig and
• Heiko Ihmels

Beilstein J. Org. Chem. 2024, 20, 3061–3068, doi:10.3762/bjoc.20.254

• is necessary to accomplish a reasonable balance between the MOST parameters. Hence, to increase the energy density and to induce a decent red shift of the absorption, two, three or even more norbornadiene units may be combined in one integral molecule by attachment to a shared, linking arene unit

• integration of an acetylene bridge between the arene core and the norbornadiene units in compounds 1h–n may induce these effects. Herein, we present the synthesis of these target molecules and our studies of their photochemical and physicochemical properties with a focus on energy conversion and storage

• ones. This lack of correlation may indicate that several different factors and processes contribute to different extent to the course of the photoreaction, for example, steric hindrance and resulting torsion angles between the arene unit and norbornadiene, deactivation of the excited state by

Advances in radical peroxidation with hydroperoxides

• Oleg V. Bityukov,
• Pavel Yu. Serdyuchenko,
• Andrey S. Kirillov,
• Gennady I. Nikishin,
• Vera A. Vil’ and
• Alexander O. Terent’ev

Beilstein J. Org. Chem. 2024, 20, 2959–3006, doi:10.3762/bjoc.20.249

Structure and thermal stability of phosphorus-iodonium ylids

• Andrew Greener,
• Stephen P. Argent,
• Coby J. Clarke and
• Miriam L. O’Duill

Beilstein J. Org. Chem. 2024, 20, 2931–2939, doi:10.3762/bjoc.20.245

• the acyclic tetrafluoroborate (1a), triflate (1b), chloride (1c) and nitrate (1d), the anion X– occupies the position trans to the arene substituent, with the ylid in the equatorial position. In tosylates 1e and 1f, as well as the cyclic and pseudocyclic structures 2 and 3, the anion or coordinating

• , with the tosylate trans to the arene in one (θ2 = 177.8) and trans to the ylid in the other (θ1 = 169.5), which suggests that this isomerisation is fast at room temperature and the position of the anion has no significant effect on the stability of these compounds. This hypothesis is further supported

• by the absence of a trans effect. While studies by Ochiai and Suresh found that strong sigma donors X cause a lengthening and weakening of the trans I–R bond in R–I(Ar)–X iodanes [32][33], little variation is observed in the I–C(ylid) (b) and I–C(arene) (c) bonds across the range of compounds

A review of recent advances in electrochemical and photoelectrochemical late-stage functionalization classified by anodic oxidation, cathodic reduction, and paired electrolysis

• Nian Li,
• Ruzal Sitdikov,
• Ajit Prabhakar Kale,
• Joost Steverlynck,
• Bo Li and
• Magnus Rueping

Beilstein J. Org. Chem. 2024, 20, 2500–2566, doi:10.3762/bjoc.20.214

• method for the regioselective thiolation of aromatic C–H bonds by activating the thiol rather than the arene [19]. For their developed reaction, Pt electrodes were used in an undivided cell with a mixture of HFIP/DCE 3:1 at room temperature under argon. Late-stage functionalization was demonstrated for

• protocol for the installation of sulfonamide groups using commercially available SO2 and amines (Scheme 12) [20]. This method is highly appealing for industrial applications and LSF. The proposed mechanism begins with the anodic oxidation of the arene substrate. The resulting radical cation intermediate is

• leelamine, racemorphan, and analogs of sertraline and celecoxib was achieved with yields ranging from 40% to 92%. The reaction mechanism begins with the photoexcitation of the intermediate [TAC2+•]*, which oxidizes the arene substrate to form a cation radical. This radical is deprotonated and then further

HFIP as a versatile solvent in resorcin[n]arene synthesis

• Hormoz Khosravi,
• Valeria Stevens and
• Raúl Hernández Sánchez

Beilstein J. Org. Chem. 2024, 20, 2469–2475, doi:10.3762/bjoc.20.211

• from intermolecular dehydration, nowadays known as alkyl resorcin[4]arene. Forty years later in 1980, Höegberg noticed that short alkyl chain resorcin[n]arenes develop stereoisomers in the reaction mixture; however, since the condensation reaction is reversible, once the macrocycle adopts the bowl

• -shaped conformation it precipitates out of solution acting as a thermodynamic sink [5][6]. Shortly after, Cram et al. recognized the potential of resorcin[n]arenes as compounds large enough to encapsulate other simple molecules or ions and group them with other known macrocyclic arene compounds, e.g

• molecular recognition [12][46]. Despite extensive research, challenges remain in the acid-catalyzed resorcin[n]arene synthesis, for example: 1) reaction times for simple resorcin[n]arenes starting from aliphatic aldehydes and resorcinol generally require multiple days and up to a week (Scheme 1a) [9][26]; 2

Oxidation of benzylic alcohols to carbonyls using N-heterocyclic stabilized λ³-iodanes

• Thomas J. Kuczmera,
• Pim Puylaert and
• Boris J. Nachtsheim

Beilstein J. Org. Chem. 2024, 20, 1677–1683, doi:10.3762/bjoc.20.149

• of 87% and 64%, respectively. Unfortunately, the synthesis of vanillin (4q) was unsuccessful due to undesirable oxidation reactions of the electron-rich arene. The cyclopropane derivative 4r was generated from the cyclopropylmethanol in 53% yield. The acetylene derivative 4s could not be isolated due

Benzylic C(sp³)–H fluorination

• Alexander P. Atkins,
• Alice C. Dean and
• Alastair J. J. Lennox

Beilstein J. Org. Chem. 2024, 20, 1527–1547, doi:10.3762/bjoc.20.137

• on the arene were unsuccessful. Without substituents on the ring, aryl C–H activation and subsequent C–O bond formation occurred along with benzylic fluorination (7) (low efficiency). The presence of a p-methoxy group resulted in a switch in selectivity to acyloxylation 8’ as the major product. The

Synthetic applications of the Cannizzaro reaction

• Bhaskar Chatterjee,
• Dhananjoy Mondal and
• Smritilekha Bera

Beilstein J. Org. Chem. 2024, 20, 1376–1395, doi:10.3762/bjoc.20.120

• proposed strategy where the metal ion acts as the binding cation template for the intramolecular desymmetrization (Scheme 15) [82]. A similar highly efficient intramolecular Cannizzaro reaction of calix[4]arene dialdehydes was observed by Galli et al. where the 1,3-distal cone 35 significantly responded to

• [4]arene dialdehydes. Desymmetrization of dialdehydes of symmetrical crown ethers using Ba(OH)2. Synthesis of ottelione A (proposed) via intramolecular Cannizzaro reaction. Intramolecular Cannizzaro reaction for the synthesis of pestalalactone. Synthetic strategy towards nigricanin involving an

Auxiliary strategy for the general and practical synthesis of diaryliodonium(III) salts with diverse organocarboxylate counterions

• Naoki Miyamoto,
• Daichi Koseki,
• Kohei Sumida,
• Elghareeb E. Elboray,
• Naoko Takenaga,
• Ravi Kumar and
• Toshifumi Dohi

Beilstein J. Org. Chem. 2024, 20, 1020–1028, doi:10.3762/bjoc.20.90

• a cartridge filled with powdered oxone® for in situ generation of bis(trifluoroacetoxyiodo)arenes and their reaction with electron-rich arene or arylboronic acid [19] (Scheme 1B). Carboxylic acids, such as acetic acid and benzoic acid, characterized by substantial difference in pKa values when

• % yield. Notably, this strategy allowed the synthesis of (diacetoxyiodo)arenes bearing acid-sensitive Boc protecting groups (1i) and heteroaromatic moieties such as pyridyl (1j) and thienyl (1k) groups. The reaction of bis(diacetoxyiodo)arene (1l) with 1,3,5-trimethoxybenzene (2.1 equiv) under the same

• , consequently yielding the desired products in high yields. However, the common synthetic methods of diaryliodonium(III) triflates involving a strong oxidizing agent with a strong acid and an electron-rich arene often resulted in black/discolored products, indicating decomposition, poor yields, and lower

(Bio)isosteres of ortho- and meta-substituted benzenes

• H. Erik Diepers and
• Johannes C. L. Walker

Beilstein J. Org. Chem. 2024, 20, 859–890, doi:10.3762/bjoc.20.78

• distance between the ortho substituents d is slightly larger in 1,5-BCH than in ortho-benzene (Figure 7) [42]. The substituent–arene angles φ2 and φ3 are similar, but the dihedral angle θ between substituents is necessarily larger in 1,5-BCHs than the near 0° angle for ortho-benzenes. Mykhailiuk and co

• ester 136g. The latter could then be oxidised to the corresponding alcohols 137f–g. The bridgehead iodine substituent could also be harnessed in iron-catalysed Kumada coupling reactions to furnish a larger number of arene-substituted 1,5-BCHeps 138. Anderson and co-workers also reported access to

Switchable molecular tweezers: design and applications

• Pablo Msellem,
• Maksym Dekthiarenko,
• Nihal Hadj Seyd and
• Guillaume Vives

Beilstein J. Org. Chem. 2024, 20, 504–539, doi:10.3762/bjoc.20.45