Stereoselective electrochemical intramolecular imino-pinacol reaction: a straightforward entry to enantiopure piperazines

• Margherita Gazzotti,
• Fabrizio Medici,
• Valerio Chiroli,
• Laura Raimondi,
• Sergio Rossi and
• Maurizio Benaglia

Beilstein J. Org. Chem. 2025, 21, 1897–1908, doi:10.3762/bjoc.21.147

• photochemical and electrochemical methods, have been explored. Over the past two decades a variety of light-promoted imino-pinacol coupling reactions have been developed, involving the use of catalytic transition-metal complexes [35][36], organic dyes [37][38][39], and polyaromatic compounds [40][41] as

Chiral phosphoric acid-catalyzed asymmetric synthesis of helically chiral, planarly chiral and inherently chiral molecules

• Wei Liu and
• Xiaoyu Yang

Beilstein J. Org. Chem. 2025, 21, 1864–1889, doi:10.3762/bjoc.21.145

• catalytic sites. The OH group on the phosphorus atom functions as a Brønsted acid site, while P=O serves as a Lewis base site, which enables the simultaneous activation of both nucleophiles and electrophiles in one reaction (Figure 1). The chiral properties of the catalysts are derived from the chiral

• chirality originating from the rigid conformation of molecules lacking symmetry, which do not fit into the aforementioned four categories, are termed inherent chirality. Notable examples include inherently chiral calix[4]arenes and saddle-shaped medium-sized cyclic compounds. Catalytic asymmetric synthesis

• molecules [9]. However, the exploration of catalytic asymmetric synthesis toward other forms of chiral elements has been relatively limited, with only a few notable instances having emerged recently. Similarly, since the initial introduction of CPA catalysts in asymmetric synthesis in 2004, a plethora of

Systematic pore lipophilization to enhance the efficiency of an amine-based MOF catalyst in the solvent-free Knoevenagel reaction

• Pricilla Matseketsa,
• Margret Kumbirayi Ruwimbo Pagare and
• Tendai Gadzikwa

Beilstein J. Org. Chem. 2025, 21, 1854–1863, doi:10.3762/bjoc.21.144

• enhance covalent and/or acid–base catalysis via any combination of non-covalent interactions (hydrogen bonding, π–π stacking, lipophilic interactions, etc) [4][5][6]. Inspired by enzymes, Nature's most efficient catalysts, chemists have long endeavored to synthesize catalytic materials in which multiple

• catalytic performance and/or systematically investigate the influence of a particular chemical or structural property on catalyst efficiency [23]. For examples of tailoring the pore environment in MOF-based catalysts to modulate catalytic performance, we can refer to the elegant work of Telfer and co

• -workers. In two separate reports, they synthesized well-defined MOFs composed of three different linkers: a proline-functionalized linker acted as the catalytic unit, while two auxiliary linkers were varied to alter catalyst activity and enantioselectivity [24], or product selectivity [25]. In those works

Fe-catalyzed efficient synthesis of 2,4- and 4-substituted quinolines via C(sp²)–C(sp²) bond scission of styrenes

• Prafull A. Jagtap,
• Manish M. Petkar,
• Vaishnavi R. Sawant and
• Bhalchandra M. Bhanage

Beilstein J. Org. Chem. 2025, 21, 1799–1807, doi:10.3762/bjoc.21.142

• [25]. However, these methods often require multiple synthetic steps and demanding conditions such as elevated temperatures, strong acidic or basic environments, and the use of expensive metal catalysts, which limit their broader applicability. To overcome these limitations, numerous catalytic

• strategies have been explored in recent decades for the synthesis of structurally diverse quinolines. Among them, transition-metal-catalyzed multicomponent reactions (MCRs) have emerged as particularly effective for constructing complex quinoline-based heterocycles [26][27][28]. Catalytic pathways such as

• cleavage as well as inadequate Lewis acid activation of N-methylaniline (1a′), which hinders its further cyclization into the final product 3a′. The reaction, when conducted in the absence of a catalyst, failed to proceed, thereby highlighting the crucial role of catalytic activation in facilitating the

Synthesis of chiral cyclohexane-linked bisimidazolines

• Changmeng Xi,
• Qingshan Sun and
• Jiaxi Xu

Beilstein J. Org. Chem. 2025, 21, 1786–1790, doi:10.3762/bjoc.21.140

• the substrate scope due to their complete rigidity. Cyclohexane-1,2-linked bisoxazolines (cHBOX) are a class of bisoxazoline ligands with the more flexible cyclohexane as linker [21][22]. Chiral cyclohexane-1,2-linked bisoxazolines fix transition states in catalytic asymmetric reactions, in whch the

• transition states can be regulated depending upon the structures of substrates, achieving excellent stereoselectivities among various substrates in the catalytic asymmetric aziridination of α,β-unsaturated ketones [21]. The steric effect of cHBOX ligands can be changed easily by the use of different chiral

• (1S,2S)-cyclohexane-1,2-dicarboxylic acid (3) and (1R,2R)-1,2-diphenylethane-1,2-diamine (1), hoping that the phenyl groups in the designed bisimidazoline ligands stemming from the vicinal diamine play an important role in the stereocontrol of catalytic asymmetric organic reactions [23][24][25][26

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

• ; single crystals; thiones; Introduction In the past several years, C–N atropisomers (C–N axially chiral compounds) owing to the rotational restriction around a C–N single bond have received great attention as new target molecules for catalytic asymmetric reactions. Highly enantioselective syntheses of

• halogen bonding observed in C–N atropisomeric quinazolinone I and quinazoline-thione II. Although the catalytic asymmetric synthesis of N-(2-bromo- or 2-chloro-phenyl)quinolin-2-ones 1a,b was recently attempted by Doerfler et al., the yields were moderate (33% and 48%) and the enantioselectivities were

Thermodynamics and polarity-driven properties of fluorinated cyclopropanes

• Matheus P. Freitas

Beilstein J. Org. Chem. 2025, 21, 1742–1747, doi:10.3762/bjoc.21.137

• isomer among the 1,2,3,4,5,6-hexafluorocyclohexanes [10]. Although it was initially synthesized via a multistep reaction, it is now readily obtainable through the catalytic hydrogenation of hexafluorobenzene [11]. Its Janus-face-like structure has demonstrated unprecedented potential, particularly due to

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

• ) and dissolved in ethanol (3 mL). A catalytic amount of Pd/C was then added and hydrogenolysis was conducted for 4 h with stirring under an H2-filled balloon. The reaction was monitored by TLC and, after completion of the reaction, the mixture was filtered through Celite, followed by washing of the

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

• ]. Diarylborinic acids have been shown to provide exclusive catalytic performance in the site-selective monofunctionalization of various 1,2- and 1,3-diols [60], as well as in the regioselective glycosylation of polyhydroxyglycosyl acceptors via base-promoted deprotonation of a specific hydroxy group involved in

• reduced reaction temperatures (−20 to −60 °C), N-phenyl trifluoroacetimidate (PTFA) donors are sufficiently stable to be used in glycosylation reactions at 0 °C or ambient temperature, while remaining reactive enough to glycosylate conformationally hindered nucleophiles in the presence of catalytic TMSOTf

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

• process hazards through the evaluation of thermal safety parameters and DFT calculations revealed catalytic and solvent effects of ionic liquids in nitration [9]. In addition, researchers have focused on improving nitration processes through process intensification strategies by integrating advanced

• . Packed-bed reactors (7%) and continuous stirred-tank reactors (CSTRs, 4%) are less prevalent, as their applications are often limited to specific scenarios – packed beds for catalytic nitration or multi-phase reactions. While small-scale chip and tubular reactors face inherent plugging risks in reactions

• nitration degree, with excess nitric acid driving reactivity at the cost of post-treatment complexity. Simultaneously, the molar ratio of H2SO4/HNO3 (usually 1.0–4.0) modulates acid strength and catalytic activity, necessitating effective balancing to optimize nitronium iongeneration efficiency while

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

• weakly nucleophilic secondary ammonium cation to the carbonyl group occurred with ΔEa = 11.5 kcal/mol (TS2→3). In recent DFT [39] and experimental [40] studies on the reductive amination reaction it was postulated that this protonation of amine played a key role in the catalytic cycle especially in the

• absence of an external hydrogen source. The alternative pathway to form a hemiaminal could not include the interaction of an acid with amine or aldehyde, nevertheless, the non-catalytic path had ΔEa = 32.1 kcal/mol (TS2→3'') which meant that hemiaminal definitely emerged faster via the amine protonation

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

• Jia-Yu Liao College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, 310058, China 10.3762/bjoc.21.129 Abstract Beyond the conventional carbon-centered chirality, catalytic asymmetric transformations of isocyanides have recently emerged as a powerful strategy for the efficient synthesis

• iodides (Scheme 1a) [27]. This transformation proceeded via two key steps, isocyanide insertion and desymmetric C(sp2)–H bond activation. By using phosphoramidite L1 as the chiral ligand, planar chiral pyridoferrocenes 2 were obtained in 61–99% yield with 72–99% ee. In addition, this catalytic system

• for Pd-catalyzed isocyanide insertion reactions, organocatalytic isocyanide-based multicomponent reactions have been explored for the synthesis of axially chiral compounds. In 2024, Yang and co-workers reported a catalytic asymmetric version of the Groebke–Blackburn–Bienaymé reaction [32][33][34

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

• of a dehydroalanine derivative using silane-mediated halogen atom transfer [28]. Dual catalytic approaches that merge photocatalysis with Lewis acid [29], organo- [30], or transition metal catalysis [31] have enabled access to bond formations that are otherwise challenging to achieve. In particular

Formal synthesis of a selective estrogen receptor modulator with tetrahydrofluorenone structure using [3 + 2 + 1] cycloaddition of yne-vinylcyclopropanes and CO

• Jing Zhang,
• Guanyu Zhang,
• Hongxi Bai and
• Zhi-Xiang Yu

Beilstein J. Org. Chem. 2025, 21, 1639–1644, doi:10.3762/bjoc.21.127

• decided to use the same approach to synthesize VI, but we planned to use a catalytic Heck reaction by using a stronger nucleophile. As can be seen below, stoichiometric Heck reaction for VI failed because the present vinyl group of the [3 + 2 + 1] product does not have a methyl group in the terminal

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

• this perspective article, we shall show the relationship between transition-state aromaticity and reactivity in representative pericyclic reactions. Perspective Lewis acid-catalyzed Diels–Alder cycloadditions It is well-established that catalytic amounts of a Lewis acid (LA) can significantly

• , which is translated into high reaction temperatures that severely limit the scope of the process. Nevertheless, as Diels–Alder cycloadditions, Alder–ene reactions can be efficiently accelerated (i.e., having lower barriers) upon the addition of catalytic amounts of a Lewis acid [62], which again

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

• diiodobenzene 5 using a Pd2(dba)3/PPh3/CuI catalytic system in toluene and Et3N under diluted conditions (monomer concentration = approximately 1.3 × 10−3 M) was performed. The corresponding cyclic dimer (Sp)-6 and trimer (Sp)-7 were detected mainly by thin-layer chromatography (TLC) and separated roughly using

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

• reagents for the preparation of 3-aryl-substituted benzo[4,5]thieno[3,2-b]pyrroles by the annulation of the 1H-pyrrole ring to the benzo[b]thiophene system (Scheme 1, reaction 6). The behavior of indoles as aza-analogs of the benzo[b]thiophenes under the identified catalytic annulation conditions is also

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

• intermediates in the synthesis of several derivatives with important applications in medicinal chemistry. Furthermore, many marketed drugs feature the enaminone structural moiety. In this context, we have developed a photoredox and nickel catalytic system to rapidly forge the enaminone scaffold from 3

• -bromochromones via a Michael reaction of an amine with an electron-deficient alkene moiety and subsequent photocatalyzed debromination. With this dual catalytic system, a range of structurally diverse enaminone derivatives have been achieved in good yields with total trans selectivity. Mechanistic studies

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

• for esters requires the development of scalable production methods. Heterogeneous CaO-based catalysts for the production of esters by transesterification are promising catalytic systems for the production of these desired compounds. In this work, the application of calcium carbide slag, a byproduct of

• ), the main phase of which is Ca(OH)2; the yield of fatty acid methyl esters was 28% (Table 1, entry 4). When using CaCO3, no formation of a mixture of fatty acid methyl esters was detected (Table 1, entry 5). Thus, the main phase of CaO in the CS600 catalyst was responsible for the catalytic activity

Heterologous biosynthesis of cotylenol and concise synthesis of fusicoccane diterpenoids

• Ye Yuan,
• Zhenhua Guan,
• Xue-Jie Zhang,
• Nanyu Yao,
• Wenling Yuan,
• Yonghui Zhang,
• Ying Ye and
• Zheng Xiang

Beilstein J. Org. Chem. 2025, 21, 1489–1495, doi:10.3762/bjoc.21.111

• activity than cotylenin A in cell growth inhibition assays and less toxicity in single-agent treatments [27][28]. Recently, Jiang and Renata described a chemoenzymatic approach that combines the skeletal construction by chemical methods and enzymatic C–H oxidations [29]. The synthesis employs a catalytic

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

• spectrum of the crude mixture (Supporting Information File 1, Figure S4). Despite its higher reductive potential, fac-Ir(ppy)3 gave a lower yield of 26% for 2aa compared to [Ru(bpy)3](PF6)2 (Table 1, entry 3). Inspired by the first positive results, we tested various cyanoarene-based catalytic systems

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

• by Son and co-workers illustrates recent advancements in the use of dioxazolones in synthetic transformations with copper salts [4]. The authors remark that these catalytic systems, which employ dioxazolones as electrophilic amide sources, were applied for the preparation of diverse amidated products

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

• , that still required high temperatures, but the excess of amine (2 equiv) was lowered and only a catalytic amount of acid was utilised. Similar acidic protocols were subsequently developed by Li et al. [46], in which benzoxazoles were reacted with secondary amines and amides, with higher temperature

• development of heterogeneous catalysis has faced challenges, due to uncertainties around catalytic sites, aggregation, and the leaching of active species during reactions. The use of a heterogeneous catalyst can greatly simplify the work-up process, as the catalyst can be easily removed via simple filtration

• indicate that MW irradiation enhances the catalytic activity of Cu toward the oxidative aromatisation of 2a-o, leading to the fast and complete conversion of the starting material to the desired 2-(piperidine-1-yl)benzoxazole (2a). Since both reactions were conducted at the same temperature, this

Wittig reaction of cyclobisbiphenylenecarbonyl

• Taito Moribe,
• Junichiro Hirano,
• Hideaki Takano,
• Hiroshi Shinokubo and
• Norihito Fukui

Beilstein J. Org. Chem. 2025, 21, 1454–1461, doi:10.3762/bjoc.21.107

• dibenzo[g,p]chrysene (DBC, 2) via oxidative inner-bond cleavage (Figure 1) [16][17]. CBBC 1 was first synthesized by Suszko and Schillak in 1934 using sodium dichromate as an oxidant [16]. Recently, our group developed a scalable, catalytic, and enantioselective protocol to furnish CBBC 1 [17]. Several

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