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

• tendencies of electronic effect on the yield and stereoselectivity were observed as those in the reactions involving 1a, but the enantioselectivities were generally higher than those in reactions involving 1a. Electron-rich benzaldehydes 2c and 2d and sterically bulky benzaldehydes 2i and 2k generated the

• of the catalyst for the next catalytic cycle. The electron-deficient aromatic aldehydes exhibit excellent stereoselectivity due to the π-stacking interaction between their aryl group and the electron-rich malonate group. Similar π-stacking interaction-controlled stereoselectivities were observed in

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

• advancements in this area have recently been demonstrated to access conjugated alkenes, particularly cinnamic acid derivatives, with high stereoselectivity. For instance, Reeves and co-workers (2023) performed a Horner–Wadsworth–Emmons reaction of triethyl 2-fluoro-2-phosphonoacetate (390) and aldehydes to

• and using ylide 397 altered the stereoselectivity to E-isomeric products 400 and 401 [144]. Wu and co-workers (2020) employed Pd to mediate the cross-coupling reaction of sulfoxonium ylide 402 and benzyl bromides to give the corresponding (Z)-ethyl cinnamates 403–406 in good yields via carbene

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

• , thereby offering unprecedented control over chemo-, regio-, and stereoselectivity parameters in catalytic manifolds. In 2015, the Jiang group developed a palladium-catalyzed regioselective three-component C1 insertion reaction (Scheme 1) [19]. In this reaction, an o-iodoaniline 1, phenylacetylene, and

• solvent-mediated electronic and steric modulations frequently dictate reaction stereoselectivity, with even subtle solvent permutations potentially inducing complete stereochemical inversion in sensitive systems [33][34][35][36][37][38]. In 2023, He and Sessler disclosed a versatile one-pot synthesis of

Regioselective formal hydrocyanation of allenes: synthesis of β,γ-unsaturated nitriles with α-all-carbon quaternary centers

• Seeun Lim,
• Teresa Kim and
• Yunmi Lee

Beilstein J. Org. Chem. 2025, 21, 800–806, doi:10.3762/bjoc.21.63

• ]. The limited investigation of allene hydrocyanation can be attributed to the significant challenges posed by the two orthogonal π-systems in allenes. These challenges include achieving high regioselectivity and controlling (E)/(Z)-stereoselectivity, as 1,2-addition processes to allenes can generate up

• allenes, the development of hydrocyanation methodologies with a broadened substrate scope and improved regio- and stereoselectivity is of significant interest. Inspired by our study on the construction of all-carbon quaternary centers via functionalized allylaluminum reagents obtained from the copper

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

• of 9 (for Z- and E-configuration, and for Re or Si side attack) should be more or less equal and the actual stereoselectivity must hence be determined in later stages of the reaction. Ligand sites in the pre-complex 9 form a pseudo-tetragonal pyramid, with isocyanide at the apex. Atoms in the Ca–NC

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

• rate and the β-stereoselectivity of the glycosylation reaction (e.g., 63 → 65 vs 64 → 66, Figure 9) [129]. Of course, the fluorine substituent remains in the product, which may or may not be advantageous depending on the particular biological context. Let us now consider furanoses (i.e., five-membered

• negative fluorine atom and the positively charged C=O+ moiety, and σC–H → σ*C–F hyperconjugation. The fluorine atom thus shields the top face of the oxocarbenium ion, and this has flow-on effects on the rate and stereoselectivity of subsequent glycosylation reactions [139]. Another important rotatable bond

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

• secondary organocopper; copper-mediated reaction; stereoselectivity; Introduction The transition-metal-catalyzed regio- and enantioselective allylic substitution represents a pivotal methodology in organic synthesis, providing remarkable versatility for complex molecule construction [1][2][3][4]. The

• complete stereocontrol. For example, the reaction of syn-alkylcopper species 14 with 3-methylbut-2-en-1-yl bromide (15) provided the corresponding SN2 product 16 in excellent yield and stereoselectivity (SN2/SN2' = >99:1, dr = 97:3). Remarkably, the regioselectivity of these reactions could be completely

• reactions with various chiral cycloallylic phosphates 17, which consistently yielded the corresponding SN2' products 18 with high stereoselectivity. The synthetic utility and broad applicability of this methodology was prominently demonstrated through the total synthesis of biologically important natural

Asymmetric synthesis of β-amino cyanoesters with contiguous tetrasubstituted carbon centers by halogen-bonding catalysis with chiral halonium salt

• Yasushi Yoshida,
• Maho Aono,
• Takashi Mino and
• Masami Sakamoto

Beilstein J. Org. Chem. 2025, 21, 547–555, doi:10.3762/bjoc.21.43

• product was obtained in moderate diastereo- and enantioselectivity, however, chloronium salt 9c did not show significant catalytic activity, and the product was formed in nearly the same yield as that obtained without a catalyst with low stereoselectivity. From these observations, bromonium salt 9a was

• (Table 1). Solvent screening was carried out, and it was found to strongly affect the product’s stereoselectivity. Non-polar solvents yielded better results, and toluene was found to be optimal (Table 1, entries 1–6). Polar solvents such as acetonitrile prohibited halogen bonding between 9a and the

• reaction; the stereoselectivity of product 17j drastically dropped. The scope for the pre-nucleophile showed that phenyl-substituted 16b provided 17k in 94% yield with high diastereoselectivity, albeit with decreased enantioselectivities. Methyl ester 16c and tert-butyl ester 16d were also applied to the

Unprecedented visible light-initiated topochemical [2 + 2] cycloaddition in a functionalized bimane dye

• Metodej Dvoracek,
• Brendan Twamley,
• Mathias O. Senge and
• Mikhail A. Filatov

Beilstein J. Org. Chem. 2025, 21, 500–509, doi:10.3762/bjoc.21.37

• crystalline compounds significantly enhances the stereoselectivity and yield of topochemical reactions compared to those conducted in solution [10]. A key requirement for these reactions is the intermolecular distance between the two reactive double bonds. Schmidt’s rule, which governs topochemical [2 + 2

Organocatalytic kinetic resolution of 1,5-dicarbonyl compounds through a retro-Michael reaction

• James Guevara-Pulido,
• Fernando González-Pérez,
• José M. Andrés and
• Rafael Pedrosa

Beilstein J. Org. Chem. 2025, 21, 473–482, doi:10.3762/bjoc.21.34

• -Michael (ReM) reaction occurs, its enantio- and diastereoselectivity, and the influence of different experimental parameters on its scope and stereoselectivity. The reaction was studied on a 1:2 mixture of the racemic diastereoisomers syn-1 and anti-1 (prepared according to our previous protocol) [25

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

• ://creativecommons.org/licenses/by/4.0). Photomechanochemical control over stereoselectivity in the [2 + 2] dimerization of acenaphthylene. The photo in Scheme 9 was republished with permission of The Royal Society of Chemistry, from [75] (“Photomechanochemical control over stereoselectivity in the [2 + 2

New tandem Ugi/intramolecular Diels–Alder reaction based on vinylfuran and 1,3-butadienylfuran derivatives

• Yuriy I. Horak,
• Roman Z. Lytvyn,
• Andrii R. Vakhula,
• Yuriy V. Homza,
• Nazariy T. Pokhodylo and
• Mykola D. Obushak

Beilstein J. Org. Chem. 2025, 21, 444–450, doi:10.3762/bjoc.21.31

• insufficiently studied furo[2,3-f]isoindole derivatives. Ugi adducts formed from (E)-3-(furan-2-yl)acrylaldehyde, maleic acid monoanilide, isonitrile, and an amine spontaneously underwent the IMDAV reaction with a high level of stereoselectivity, leading to single pairs of enantiomers of 4,4a,5,6,7,7a-hexahydro

• investigate the possibility of obtaining related compounds in the Ugi/IMDAV reaction. It was found that the reaction of (E)-3-(thiophen-2-yl)acrylaldehyde proceeds similarly to furylacrylaldehyde and with a high level of stereoselectivity, forms a single pair of enantiomers of 4,4a,5,6,7,7a-hexahydro-3aH

The effect of neighbouring group participation and possible long range remote group participation in O-glycosylation

• Rituparna Das and
• Balaram Mukhopadhyay

Beilstein J. Org. Chem. 2025, 21, 369–406, doi:10.3762/bjoc.21.27

• exhibits comparatively less efficacy in achieving complete stereoselectivity in the glycosylation reactions. Remote participation is a still highly debated topic in the scientific community. However, implementing the participating role of the remote groups in glycosylation reactions is widely practised to

• carbohydrate moieties [20][21][22] coupled with the need for suitable anomeric stereoselectivity [23]. Over the decades, there have been widespread studies to standardise and optimise glycosylation reactions, but a standard reaction protocol still eludes the scientific community. We will give a generalised

• protecting groups as remote groups and analyse the various critical viewpoints pertaining to their distal contribution in determining the stereoselectivity of the glycosylation reactions. The comprehensive knowledge of the role of the protecting groups in glycoside reactions in the different positions

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

• standard conditions. Subsequently, radical-polar coupling between electrophilic Ni-bound α-carbonyl radical intermediate 45 and remaining nucleophilic Cu-enolate 44 provides a chiral product 42 containing vicinal quaternary stereocenters with high stereoselectivity, and all three possible stereoisomers of

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

• and sulfur dioxide afforded vinyl sulfones with excellent regio- and stereoselectivity (Scheme 9) [22]. The authors used DABCO(SO2)2 to generate sulfur dioxide, and visible light irradiation and the mandatory presence of a photocatalyst for this transformation suggested a radical mechanism. The

• -methylthiazole-2-carboxaldehyde as chelating agent, in the presence of copper triflate and the chiral diamine ligand 28. The stereoselectivity was directed by the formation of a proposed catalyst complex 29 involving two molecules of Schiff base (Scheme 22) [39]. The three-component annulation of aldehydes

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

• stereoselectivity (96% ee, >95:5 dr). No racemization was observed after 36 hours at 150 °C in o-xylene. The asymmetric synthesis of arylindolylindolinones 139 or 141 bearing both central and axial chirality was accomplished by a combination of arylindoles 137 or 140 and indolinones 138 with CPA (R)-C22 acting as

• . Experiments determining the configurational stability were done in both toluene at 120 °C and o-xylene at 150 °C for up to 36 h with retained stereoselectivity but decreasing yields at higher temperatures for prolonged periods of time. The possible activation mode explains the stereocontrol of the reaction

• intermediate Int-53. Control experiments confirmed that this structure could undergo successive reduction and oxidation through intermediate Int-54 to give benzylimine intermediate Int-55. Alternatively, a direct [1,5]-H migration of Int-53 also leads to Int-55. The stereoselectivity of the product is

Non-covalent organocatalyzed enantioselective cyclization reactions of α,β-unsaturated imines

• Sergio Torres-Oya and
• Mercedes Zurro

Beilstein J. Org. Chem. 2024, 20, 3221–3255, doi:10.3762/bjoc.20.268

• except for azadienes bearing a bulky t-Bu substituent, which led to the Michael product 27e’ albeit with low stereoselectivity. The authors proposed a plausible reaction mechanism to explain the observed stereoselectivity of the reaction. Firstly, the isocyanoacetate is deprotonated by the tertiary amine

• . Then, an intramolecular aldol reaction leads to intermediate D which undergoes final protonation to produce the desired chiral product 43f. The authors proposed that the stereoselectivity of the Michael addition product would direct the stereoselectivity of the intramolecular aldol reaction. To

• excellent enantioselectivities (97–99% ee) using also chiral phosphoric acid XIV (Scheme 17). The authors proposed a reaction mechanism in order to explain the observed stereoselectivity of the products in which through hydrogen bonding the chiral phosphoric acid provides a chiral environment where the

Synthesis of extended fluorinated tripeptides based on the tetrahydropyridazine scaffold

• Thierry Milcent,
• Pascal Retailleau,
• Benoit Crousse and
• Sandrine Ongeri

Beilstein J. Org. Chem. 2024, 20, 3174–3181, doi:10.3762/bjoc.20.262

• the ester function, as previously reported [32][33][34][35]. The corresponding adducts 5a–f were isolated with good yields from 66 to 88%. In the case of hydrazides 5e and 5f, the mixture of diastereomers (1:1 ratio) could not be separated at this stage. Although no stereoselectivity is observed, it

• strategy, the control of the stereoselectivity of the intramolecular aza-Michael addition could be envisaged with various chiral catalysts in further studies. These heterocyclic hydrazino acids, when incorporated into the peptidic structure, appear to confer an extended conformation. These interesting

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

• stereochemistry of the reaction. Linear chiral catalysts were found to offer higher stereoselectivity compared to spiro-catalysts. Under optimized conditions, the asymmetric aminofluorination of N-cinnamylbenzamides 37 using BF3·Et2O as the fluorine reagent demonstrated good yields and high stereoselectivity

Tunable full-color dual-state (solution and solid) emission of push–pull molecules containing the 1-pyrindane moiety

• Anastasia I. Ershova,
• Sergey V. Fedoseev,
• Konstantin V. Lipin,
• Mikhail Yu. Ievlev,
• Oleg E. Nasakin and
• Oleg V. Ershov

Beilstein J. Org. Chem. 2024, 20, 3016–3025, doi:10.3762/bjoc.20.251

• containing various numbers of substituents at the donor site, which differed in their electron-donating strength, was obtained. It was found that the reaction of pyridine 2 with aromatic aldehydes occurred with complete stereoselectivity – only the E-isomer was obtained as the reaction product. The

gem-Difluorovinyl and trifluorovinyl Michael acceptors in the synthesis of α,β-unsaturated fluorinated and nonfluorinated amides

• Monika Bilska-Markowska,
• Marcin Kaźmierczak,
• Wojciech Jankowski and
• Marcin Hoffmann

Beilstein J. Org. Chem. 2024, 20, 2946–2953, doi:10.3762/bjoc.20.247

• , we observed a striking illustration of this phenomenon. A Michael addition involving gem-difluorovinyl and trifluorovinyl acceptors was successfully achieved, demonstrating high stereoselectivity. This selectivity was further elucidated through theoretical calculations. Using this methodology, a

• products. These highly stable compounds were isolated after purification on silica gel in good yields (Scheme 2) and characterized by spectroscopic methods. The reaction proceeded with very high Z-stereoselectivity (Scheme 2, compounds 9a–d). In the 19F NMR spectra of crude mixtures, only trace amounts of

• remarkable stereoselectivity, a finding elucidated by DFT analysis. These results mark significant progress toward the synthesis of novel fluorinated building blocks. Our team is currently exploring the application of this methodology to amino acid substrates, aiming to contribute further to the burgeoning

Recent advances in transition-metal-free arylation reactions involving hypervalent iodine salts

• Ritu Mamgain,
• Kokila Sakthivel and
• Fateh V. Singh

Beilstein J. Org. Chem. 2024, 20, 2891–2920, doi:10.3762/bjoc.20.243

• , including di- and trisubstituted ones, were well tolerated in the reaction, providing products 24 with good stereoselectivity in moderate to good yields. Moreover, the reaction was successfully conducted with various substituted vinyl pinacol boronates and di(4-tolyl)iodonium triflate, resulting in moderate

Copper-catalyzed yne-allylic substitutions: concept and recent developments

• Shuang Yang and
• Xinqiang Fang

Beilstein J. Org. Chem. 2024, 20, 2739–2775, doi:10.3762/bjoc.20.232

• developments and illustrates the influences of copper salt, ligand, and substitution pattern of the substrate on the regioselectivity and stereoselectivity. Keywords: copper-catalysis; copper vinyl allenylidene intermediate; 1,3-enyne; 1,4-enyne; yne-allylic substitution; Introduction Copper is earth

Computational design for enantioselective CO₂ capture: asymmetric frustrated Lewis pairs in epoxide transformations

• Maxime Ferrer,
• Iñigo Iribarren,
• Tim Renningholtz,
• Ibon Alkorta and
• Cristina Trujillo

Beilstein J. Org. Chem. 2024, 20, 2668–2681, doi:10.3762/bjoc.20.224

• adduct with a relative free energy of 0.7 kcal·mol−1. Thus, the evaluation of the stereoselectivity of the designed catalyst was conducted by only studying the steps after the capture of CO2 by the catalyst. The reaction occurs in two steps (Table 1). Initially, a pre-TS assembly, with the PO compound

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