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

• Linqiang Wang and
• Jiaxi Xu

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

• ). Other rare-earth salts, including Y(OTf)3, La(OTf)3, Sm(OTf)3, Tb(OTf)3, Er(OTf)3, and Lu(OTf)3, were also screened, but no better results were observed (Table 1, entries 6–11). In addition, different ligands L2–L4 were evaluated (Table 1, entries 12–14). The enantiomer of product 3aa was obtained in 28

• % yield with 31% ee and >20:1 diastereomeric ratio in the presence of ligand L2 (Table 1, entry 12). However, ligands L3 and L4 were completely inactive. Thus, further optimizations were performed with 10 mol % of Sc(OTf)3 and L1. The reaction was conducted at different temperatures for 12 h for saving

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

• product 245 or the corresponding Z-isomeric product 246, both in good yields. Alkenyl sulfides have also been used for the preparation of cinnamic acid esters. For example, Wu and co-workers (2020) studied the Pd-catalyzed carbonylation of alkenyl sulfides in the presence of NHC ligands via C–S cleavage

Pd-Catalyzed asymmetric allylic amination with isatin using a P,olefin-type chiral ligand with C–N bond axial chirality

• Natsume Akimoto,
• Kaho Takaya,
• Yoshio Kasashima,
• Kohei Watanabe,
• Yasushi Yoshida and
• Takashi Mino

Beilstein J. Org. Chem. 2025, 21, 1018–1023, doi:10.3762/bjoc.21.83

• amination of allyl esters using isatin as a nucleophile. In this reaction, bisphosphine-type ligands such as BINAP and SEGPHOS derivatives, as well as P,N-type ligands like oxazoline-type ligands, were utilized as chiral ligands [26]. On the other hand, several groups have recently reported new chiral

• ligands with axial chirality for Pd-catalyzed asymmetric allylic substitution reactions. For example, the Zhou group reported a P,olefin-type chiral ligand 3 with C–C bond axial chirality for this reaction (Figure 2) [27]. Additionally, we have recently reported chiral ligands with C–N bond axial

• chirality, such as N-alkyl-N-cinnamyl-type chiral ligands 4 [28][29] and 5 [30], and a P,olefin-type chiral ligand 6 [31] with a cinnamoyl group instead of a cinnamyl group. In particular, the chiral ligand 6 is effective in the Pd-catalyzed asymmetric allylic substitution reaction of allylic esters with

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

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

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

• efficient for related transformations [28][29]. However, only a yield of 15% of the desired product 4a was obtained after stirring for 15 hours, due to low conversion of the starting material. Subsequently, different mono- and bidentate ligands were tested. DPEphos was found to be the most potent ligand

• , leading to 43% isolated yield with full conversion of starting material and different byproducts derived from decomposition. Interestingly, no conversion of the starting material could be observed with the other ligands. In the following, different solvents, temperatures and bases were tested, but did not

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

Recent advances in controllable/divergent synthesis

• Jilei Cao,
• Leiyang Bai and
• Xuefeng Jiang

Beilstein J. Org. Chem. 2025, 21, 890–914, doi:10.3762/bjoc.21.73

• literatures focusing on key regulatory factors for product divergent formation, in which controlling chemical selectivity primarily relies on ligands, metal catalysts, solvents, time, temperature, acids/bases, and subtle modifications of substrates. To gain a deeper understanding of the mechanisms underlying

• review systematically examines, how these multidimensional control elements (including ligands, metal catalysts, solvents, time, temperature, acids/bases, and subtle modifications of substrates) synergize to achieve predictable product diversification. In addition, mechanistic insights are discussed

• , enabling programmable access to structurally distinct molecular architectures from identical substrate precursors through precise manipulation of metal coordination [16][17][18]. This sophisticated approach capitalizes on the stereoelectronic tunability of ancillary ligands to dictate reaction pathways

Light-enabled intramolecular [2 + 2] cycloaddition via photoactivation of simple alkenylboronic esters

• Lewis McGhie,
• Hannah M. Kortman,
• Jenna Rumpf,
• Peter H. Seeberger and
• John J. Molloy

Beilstein J. Org. Chem. 2025, 21, 854–863, doi:10.3762/bjoc.21.69

• ). Efficient EnT catalysis could be achieved with neutral trigonal planar systems 1a–d, while BMIDA substrate 1e was also effective presumably due to the proposed hemilabile nature of the MIDA protecting group in acetonitrile [58]. More electron-donating ligands such as 1,8-diaminonaphthalene (BDAN, 1f) were

Chitosan-supported CuI-catalyzed cascade reaction of 2-halobenzoic acids and amidines for the synthesis of quinazolinones

• Xuhong Zhao,
• Weishuang Li,
• Mengli Yang,
• Bojie Li,
• Yaoyao Zhang,
• Lizhen Huang and
• Lei Zhu

Beilstein J. Org. Chem. 2025, 21, 839–844, doi:10.3762/bjoc.21.67

• promote this cascade reaction for the synthesis of quinazolinones without the need for additional ligands or additives (Scheme 1a) [7][10]. Since then, various copper-based catalysts, both homogeneous and heterogeneous, have been explored (Scheme 1b) [11][12][13][14][15][16]. For example, Wang’s group

4-(1-Methylamino)ethylidene-1,5-disubstituted pyrrolidine-2,3-diones: synthesis, anti-inflammatory effect and in silico approaches

• Nguyen Tran Nguyen,
• Vo Viet Dai,
• Luc Van Meervelt,
• Do Thi Thao and
• Nguyen Minh Thong

Beilstein J. Org. Chem. 2025, 21, 817–829, doi:10.3762/bjoc.21.65

• well as ADMET properties. All compounds satisfied these criteria, indicating favorable oral bioavailability. Molecular docking analysis showed that compounds 5a–e act as ligands for inducible nitric oxide synthase (iNOS), especially with Cys200 and Ser242 via hydrogen bonds. In addition, van der Waals

• ligands (Figure 4 and Figure 5). Additionally, dexamethasone (DEX) was employed as an experimental control for comparative purposes [34][35][36]. The docking scores (DS), reported in Table 5 as binding affinities, reveal that negative DS values correspond to stronger binding affinities between the ligand

• that all ligands consistently interacted with Cys200 and Ser242, key residues in the enzyme's active site, underscoring their critical role in ligand stabilization. In addition to hydrogen bonding, extensive van der Waals interactions were observed, particularly involving residues such as Thr190

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

• efficiency of reactions [14][15][16][17][18][19][20][21]. Organophosphorous compounds are essential materials with broad applications in medicinal chemistry, synthesis, agriculture, as ligands, and intermediates to prepare complex compounds. Due to their importance, scientists have introduced many studies in

Development and mechanistic studies of calcium–BINOL phosphate-catalyzed hydrocyanation of hydrazones

• Carola Tortora,
• Christian A. Fischer,
• Sascha Kohlbauer,
• Alexandru Zamfir,
• Gerd M. Ballmann,
• Jürgen Pahl,
• Sjoerd Harder and
• Svetlana B. Tsogoeva

Beilstein J. Org. Chem. 2025, 21, 755–765, doi:10.3762/bjoc.21.59

• applications of calcium complexes with axially chiral BINOL phosphate ligands have been reported in recent years [28][32][33][34][35][36][37][38], as well as complexes with other chiral phosphoric acid ligands [39]. Since then, other main group metal complexes with BINOL phosphate ligands have been discovered

• hydrocyanation of hydrazone 1 towards product 2 (Table 1) using an achiral model calcium-based catalyst (4, Figure 1) with monodentate biphenyl phosphate ligands. This model catalyst 4, derived from the literature-known phosphoric acid BIPO4-H 3 [51], was synthesized by reacting 3 with Ca(OiPr)2 under inert

• conditions. The product was isolated as colorless crystals in good yield of 81% (Scheme 1). Complex 4 crystallizes as a C2-symmetric chiral mononuclear complex in which Ca is bound to two monodentate phosphate ligands (Figure 1). Four MeOH ligands complete the slightly distorted octahedral coordination

Orthogonal photoswitching of heterobivalent azobenzene glycoclusters: the effect of glycoligand orientation in bacterial adhesion

• Leon M. Friedrich and
• Thisbe K. Lindhorst

Beilstein J. Org. Chem. 2025, 21, 736–748, doi:10.3762/bjoc.21.57

• ) is depicted as ribbon diagram and the ligands are displayed as stick models (glycoclusters 1 and 2: EE: blue; ZZ: violet; EZ: green; ZE: red). Superposition of the isomers shows the similarity of the binding of the terminal mannoside antenna within the FimH CRD and the different orientations of the

• ), resulting half-lifes (τ1/2) and activation energies (Ea) for the thermal ZZ to EE isomerization of glycoclusters 1 [24] and 2 and thermal Z to E isomerization of the glycoantennas 3, 4, and 5 at 37 °C. The top-ranked results of the molecular modeling study of the various isomers of the ligands 6βGlc3αMan 1

Synthesis of HBC fluorophores with an electrophilic handle for covalent attachment to Pepper RNA

• Raphael Bereiter and
• Ronald Micura

Beilstein J. Org. Chem. 2025, 21, 727–735, doi:10.3762/bjoc.21.56

• -cyanophenylacetonitrile afforded HBC 4 and HBC-like ligands 5 and 6 as bright orange solids. Finally, the bromo group was introduced under Appel conditions with carbon tetrabromide and triphenylphosphine to give the fluorophores 7, 8, and 9, with linker lengths of two, three, and five atoms. Unfortunately, this strategy

• usefulness of this type of bifunctional fluorescent ligands in RNA affinity purification has recently been demonstrated by our group [11]. Conclusion Covalent fluorescent light-up aptamers (coFLAPs) are opening new avenues for RNA imaging [11]. In this work, we describe robust synthetic routes for twelve HBC

• mixture was poured on a silica gel column and the product was eluted using 0–1% methanol in dichloromethane. In vitro reaction of BrC3 or MsOC3 ligands with Pepper RNA. In a manner analogous to [11], a typical alkylation reaction was carried out in a volume of 60 µL. Pepper RNA (0.15 nmol) was dissolved

Acyclic cucurbit[n]uril bearing alkyl sulfate ionic groups

• Christian Akakpo,
• Peter Y. Zavalij and
• Lyle Isaacs

Beilstein J. Org. Chem. 2025, 21, 717–726, doi:10.3762/bjoc.21.55

• [n])), and those prepared by metal ligands and H-bonding self-assembly processes [1][2][10][11][12][13][14][15][16][17][18][19][20]. Macrocycles have played key roles in important real-world products including the household deodorizer FebreezeTM, glucose monitors, and as solubilizing excipients [21

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

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

• phosphoramidite ligands significantly advanced this field, with contributions from numerous research groups including Hartwig, Helmchen, Carreira, Alexakis, and You [19]. In general, soft nucleophiles that typically possess conjugate acids with pKa values less than 25 have been utilized in most Pd and Ir

• their exploration of phosphoramidite ligands with various organometallic nucleophiles [24][25]. The field was further advanced by the research group of Hoveyda, who made substantial contributions by introducing bidentate N-heterocyclic carbene (NHC)-based chiral ligands, achieving high selectivity with

Synthesis of electrophile-tethered preQ₁ analogs for covalent attachment to preQ₁ RNA

• Laurin Flemmich and
• Ronald Micura

Beilstein J. Org. Chem. 2025, 21, 483–489, doi:10.3762/bjoc.21.35

• Laurin Flemmich Ronald Micura Institute of Organic Chemistry, Center for Molecular Biosciences Innsbruck (CMBI), Innrain 80-82, 6020 Innsbruck, Austria 10.3762/bjoc.21.35 Abstract The preQ1 cIass-I riboswitch aptamer can utilize 7-aminomethyl-7-deazaguanine (preQ1) ligands that are equipped with

• such reactive preQ1 and (2,6-diamino-7-aminomethyl-7-deazapurine) DPQ1 ligands. The readily accessible key intermediates of preQ0 and DPQ0 (both bearing a nitrile moiety instead of the aminomethyl group) were reduced to the corresponding 7-formyl-7-deazapurine counterparts. These readily undergo

• vitro and in living cells using rationally designed electrophile-tethered derivatives of preQ1 (1) and its Watson–Crick diamino-faced counterpart DPQ1 (2, Scheme 1A). These ligands (compound classes 3 and 4, Scheme 1A) were tailored to target a conserved guanine nucleobase within a natural preQ1-binding

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

• spectroscopy (Scheme 1). During the reaction progress, the C=C bonds of bpe ligands undergo pedal-like motion prior to photodimerization [63]. For the single-crystal irradiation, the slow reactivity can be attributed to the hindered pedal motion in the single crystals, likely due to the presence of

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

• the cage framework to polarize adjacent aryl–hydrogen bonds in the ligands by enough to coordinate and activate substrates (Figure 5E) [190]. Here, the use of bulky counteranions reinforces the cationic cage interior, which is enhanced further by use of lower polarity solvents, and the pKa of confined

• transform the ligands can result in changes in cage topology distribution [204]. Self-assembly can also prescribe limitations on the symmetry of cages [36]. Notably, Clever has recently reported the first Pd2(ABCD) MOC [205], which may signal the possibility of using low-symmetry cavities [206][207][208

• -based porous organic cages have been a popular choice for study [377][379][406][407][408], as have MOCs [208][376][386]. Much focus remains on the prediction (and automation) [409] of the formation of cavities by probing combinations of, e.g., amines/aldehydes or metals/ligands to identify structures

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

• , exceptional thermal and chemical stability, and robust synthetic versatility [16][17] – make carborane derivatives essential components in various fields. These include pharmaceuticals [18][19][20][21][22], boron neutron capture therapy (BNCT) [23][24][25][26], organometallic ligands [27], and functional

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

• own a large span of colors depending on the nature of the metal and the ligands but also on the various oxidation states these compounds can attain. This property results on the absorption of a visible-light photon complementary to the observed color and has been extensively exploited in photoredox

• of lower-energy photons in second- and third-row transition metals compared to their first-row counterparts [13]. These phenomena are specifically improved when potent π-acceptor ligands are used due to their low-energy π* antibonding orbitals resulting in a bathochromic shift of the MLCT absorption

• -row d6 metal complexes such as Fe(II) complexes and positions Cr(0) as a promising alternative in photoredox applications under low-energy red-light conditions. The enhanced performance of these Cr(0) complexes is attributed to their strong ligand field, provided by the isocyanide ligands, which

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

• enantioselectivity is the introduction of serine-derived bisoxazoline ligands L8 (sBOX). Upon coordination with a copper catalyst, these ligands present second-sphere ester groups, which facilitate the additional stabilization of noncovalent interactions at the penta-coordinated Cu(III) intermediate 82 in the

• reactions of copper catalysts without ligands face limitations owing to slow electron transfer kinetics, irreversible copper plating, and competing substrate oxidation. To overcome these challenges, Sevov et al. developed a ligand-free, Cu-catalyzed electrochemical Chan–Lam coupling using a ferrocenium salt

Nickel-catalyzed cross-coupling of 2-fluorobenzofurans with arylboronic acids via aromatic C–F bond activation

• Takeshi Fujita,
• Haruna Yabuki,
• Ryutaro Morioka,
• Kohei Fuchibe and
• Junji Ichikawa

Beilstein J. Org. Chem. 2025, 21, 146–154, doi:10.3762/bjoc.21.8

• , entry 3). Reducing the catalyst loading to 5 mol % slightly affected the yield of 3bb, which was 90% (Table 1, entry 4). Next, we evaluated various additives with 5 mol % of Ni(cod)2 to stabilize regenerated zero-valent nickel species (Table 1, entries 5–8). While phosphine ligands such as triphenyl

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

• counteranion. The use of a carbamate among the substrates instead of the amine allowed the synthesis of propargylcarbamates 11. This reaction, effective only for the aromatic aldehydes, did not require other co-catalysts or ligands (Scheme 8) [21]. Three-component reactions of alkynes, alkyltrifluoroborates

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

• compounds comprising a stereogenic plane or axis is much less developed. Axially chiral compounds are well known as chiral ligands in asymmetric catalysis, with notable examples of binaphthyl-based derivatives such as BINAP, SEGPHOS, or binaphthyl-based phosphoric acid derivatives, which are among the

• purities, solid yields and very good diastereomeric ratios. The hydroxy group present in products 156 and 158 could be transformed to provide axially chiral phosphines that could be utilized as chiral ligands in transition-metal-catalyzed reactions. Testing both substrates 156 and 158 for conformational