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

• internal rotation in 11 via TS8 and reaction with TMSCN to give adduct 13 (see Figure 3). Distances and bond lengths are given in pm. Catalyst 7 is replaced in TS 11-12 by concerted electrophilic intramolecular substitution with formal trimethylsilyl cation as electrophile. Please note the surprisingly

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

• to avoid precipitation of the compounds 7, 8, 9, and 11 during long (>12 h) incubation times). In view of these results, we further focused on HBC derivatives with the high-yielding C3 handle and sought a variation of the electrophile. Thus, adapted Appel reaction conditions using N-chlorosuccinimide

• RNA. Key is the functionalization of the original N-(2-hydroxyethyl) moiety into a reactive handle providing a mild electrophile (LG), such as, e.g., N-(3-bromopropyl) or N-(3-mesyloxypropyl) [11]. Pepper aptamer reacts with different HBC derivatives. Chemical structures of the HBC derivatives used

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

• dependent on both the leaving group of the allylic electrophile and the choice of the supporting ligand. When (+)-1,2-bis{(2S,5S)-2,5-diphenylphospholano}ethane {(S,S)-Ph-BPE} (L1) was employed as the supporting chiral ligand, initially allylic chloride was found to provide the desired product 32 with

• the competing transition states showed that the chiral α-borylalkylcopper species 37 could approach the olefinic moiety of allylic electrophile 35 from either the re- or si-face. The re-face approach is energetically favored, minimizing steric interactions between the bulky aryl substituent of NHC

• ligand L3 and the allylic electrophile 35. In contrast, a si-face attack leads to a higher-energy transition state due to significant steric repulsion. Enantioselective hydroallylation of vinyltrifluoromethyl compounds The direct functionalization of 1-trifluoromethylalkenes 38 through copper catalysis

Photocatalyzed elaboration of antibody-based bioconjugates

• Marine Le Stum,
• Eugénie Romero and
• Gary A. Molander

Beilstein J. Org. Chem. 2025, 21, 616–629, doi:10.3762/bjoc.21.49

• transformations is a strong electrophile that can react with Tyr, for instance, if such an amino acid is located near the reactive site. In addition, command of the DAR might have some limits, as the distance between the catalyst and the mAbs is not well defined, meaning that the photoredox reaction might not

• method allows the same photocatalyst and electrophile to be involved in two different but selective bioconjugations of mAbs. It remains limited to reactions involving oxidative mechanistic pathways with 1O2. Cys In 2016, Bräse et al. developed a photomediated disulfide rebridging method, exploiting the

Formaldehyde surrogates in multicomponent reactions

• Cecilia I. Attorresi,
• Javier A. Ramírez and
• Bernhard Westermann

Beilstein J. Org. Chem. 2025, 21, 564–595, doi:10.3762/bjoc.21.45

• products (products 2 to 5, Scheme 4). In other cases, under acidic and thermal conditions, DMSO can undergo a Pummerer-type process in which, upon activation of the sulfoxide oxygen, a reactive methyl(methylene)sulfonium ion (MMS) is formed (Scheme 5) that acts as an active electrophile. Depending on the

Vinylogous functionalization of 4-alkylidene-5-aminopyrazoles with methyl trifluoropyruvates

• Judit Hostalet-Romero,
• Laura Carceller-Ferrer,
• Gonzalo Blay,
• Amparo Sanz-Marco,
• José R. Pedro and
• Carlos Vila

Beilstein J. Org. Chem. 2025, 21, 533–540, doi:10.3762/bjoc.21.41

• ] as electrophiles. It is noteworthy that the development of such vinylogous functionalizations of this nitrogen heterocycle with a fluorine-containing electrophile may be of interest to pharmaceutical and medicinal chemists. Results and Discussion 4-(Alkenyl)-5-aminopyrazoles 3 were selected as

• electrophile activation. In certain reactions, we isolated compound A, the hydrate of methyl trifluoropyruvate. We hypothesized that preventing the formation of this byproduct could improve the reaction yield by using molecular sieves (entries 17 and 18, Table 1). However, when molecular sieves were added, the

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

• 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

• of the electrophile. We thus identified aldehydes 9 and 10 as suitable branching points, which were easily derivatized to their aminomethyl-modified preQ1 analogs by reductive amination (Scheme 3). Their syntheses by Raney-Ni reduction of nitriles 7 and 8, previously described by Gangjee and co

• . First, the alkyl handles bearing a primary hydroxy group were introduced and then converted into the electrophile of choice. More specifically, to furnish compounds 4b–d, precursor 9 was treated with the corresponding amino alcohols in the presence of a desiccant. The imines formed were subjected to

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

• nucleophile and electrophile) [5][6][7][8][9][10][11][12]. Crucially, enzymes organize their polarization – they achieve both components in tandem. Supramolecular chemists have made significant advances in cavity catalysis [13][14][15][16][17][18][19][20][21][22][23][24] – albeit slowly [25] – but have

• electrophile [175]. In terms of polarization, since cages are invariably charged [36], a few MOCs have demonstrated charge stabilization of transition states (Figure 5B). A key example uses the highly successful Raymond gallium-based cages, exploited by Raymond, Bergman and Toste [21][37][107][155][165][168

• triad (red) was hoped to activate the benzyl alcohol nucleophile, but it does not activate (polarize) the electrophile (substrate ester group). (B) One of Rebek’s “clefts” [108][109]. The rigidly organized carboxylic acids both bind the substrate and the transition state for hydrolysis of an acetal. (A

Dioxazolones as electrophilic amide sources in copper-catalyzed and -mediated transformations

• Seungmin Lee,
• Minsuk Kim,
• Hyewon Han and
• Jongwoo Son

Beilstein J. Org. Chem. 2025, 21, 200–216, doi:10.3762/bjoc.21.12

• 1.0 equiv of 19 were used. Copper-catalyzed asymmetric hydroamidation of vinylarenes. a4 mol % + 2 mol % catalyst was used. b4 mol % + 4 mol % catalyst was used. cSlow addition of the amide electrophile solution. Copper-catalyzed anti-Markovnikov hydroamidation of alkynes. Copper-catalyzed preparation

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

• Figure 11. Initially, the Cu(II) catalyst 50 coordinates with substrate 47 and amine electrophile 48 to generate Cu(II) intermediate 51, which is then oxidized by the iodine radical to form Cu(III) complex 52. Cu(III) complex 52 undergoes electron transfer to produce radical cation intermediate 53

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

• ring was obtained using the same reaction as previously reported for PHn (Figure 1) [45], between 2,2’-dilithiobiphenyl derivatives but this time with the electrophile decafluorobiphenyl C6F5–C6F5 instead of C6H5–C6F5 (Fn, n = 3–12, Scheme 1). The presence of the terminal fluoroarene group in Fn

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

• reviews [17][18]. Review Hydrogen bond donors: bifunctional thioureas and squaramides The use of bifunctional catalysts is commonplace in organocatalyzed transformations [19][20][21][22][23]. These catalysts are able to activate an electrophile and a nucleophile simultaneously and in IEDADA reactions they

Enantioselective regiospecific addition of propargyltrichlorosilane to aldehydes catalyzed by biisoquinoline N,N’-dioxide

• Noble Brako,
• Sreerag Moorkkannur Narayanan,
• Amber Burns,
• Layla Auter,
• Valentino Cesiliano,
• Rajeev Prabhakar and
• Norito Takenaka

Beilstein J. Org. Chem. 2024, 20, 3069–3076, doi:10.3762/bjoc.20.255

• propargyltrichlorosilane and significantly activates the C1–H1 bond (1.11 Å). It is noteworthy that the nitrogen atom can also interact with the Si atom of propargyltrichlorosilane which is a stronger electrophile compared to the H1 atom. However, the bulky groups around nitrogen and three chlorine atoms coordinated to Si

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

• also tried to perform a substitution reaction by treating compounds 1a and 2a with tert-BuLi, employing methyl iodide as the electrophile. However, similar to previous reactions, this did not yield substitution products at the alpha position, but to the addition–elimination reaction products. More

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

• K2CO3 at 55 °C to yield the corresponding products 62 in good to excellent yield (Scheme 25) [76]. It was observed that both electronic as well as steric effects on the aryl electrophile and phenol nucleophile were well tolerated. Further, this study was used for the one-pot synthesis of diaryl ethers

Synthesis of spiroindolenines through a one-pot multistep process mediated by visible light

• Francesco Gambuti,
• Jacopo Pizzorno,
• Chiara Lambruschini,
• Renata Riva and
• Lisa Moni

Beilstein J. Org. Chem. 2024, 20, 2722–2731, doi:10.3762/bjoc.20.230

• reacts with an isocyanide and an electron-rich aniline in a three-component Ugi-type reaction to give an α-aminoamidine. This compound might undergo an additional visible light-mediated oxidation to furnish a second iminium intermediate, which acts as electrophile in an intramolecular electrophilic

Stereoselective mechanochemical synthesis of thiomalonate Michael adducts via iminium catalysis by chiral primary amines

• Michał Błauciak,
• Dominika Andrzejczyk,
• Błażej Dziuk and
• Rafał Kowalczyk

Beilstein J. Org. Chem. 2024, 20, 2313–2322, doi:10.3762/bjoc.20.198

• reactivity by chiral quaternary ammonium salt in the asymmetric variant of the phase-transfer catalysis. Nevertheless, no product was formed despite several conditions being examined. Finally, an attempt to activate the electrophile was performed. We chose iminium salt catalysis particularly employing chiral

• stabilized by an intramolecular hydrogen bond with a protonated amine unit activates the Michael acceptor (Scheme 4). Moreover, a strong but reversible covalent bond locates the electrophile upon the quinoline unit of the catalyst and thus subsequently blocks the bottom approach of the thiomalonate. Hence

• -thiomalonate 3 was applied to cyclopentenone, which exhibits electrophilicity on the Mayer scale of −20.60 compared to cyclohexenone (E = −22.10, in DMSO) [41], comparable results were obtained both in solution and in a ball mill (Scheme 5). Therefore, a slightly more reactive electrophile does not

Catalysing (organo-)catalysis: Trends in the application of machine learning to enantioselective organocatalysis

• Stefan P. Schmid,
• Leon Schlosser,
• Frank Glorius and
• Kjell Jorner

Beilstein J. Org. Chem. 2024, 20, 2280–2304, doi:10.3762/bjoc.20.196

• the ML model by being considered as a nucleophile or electrophile, depending on the reaction mechanism. Descriptors allowed for the inclusion of a variety of co-catalysts, ranging from Fe-piano stool complexes to copper complexes. The consideration of co-catalysis into model development further

Multicomponent syntheses of pyrazoles via (3 + 2)-cyclocondensation and (3 + 2)-cycloaddition key steps

• Ignaz Betcke,
• Alissa C. Götzinger,
• Maryna M. Kornet and
• Thomas J. J. Müller

Beilstein J. Org. Chem. 2024, 20, 2024–2077, doi:10.3762/bjoc.20.178

• that ninhydrin (150), as an electrophile, reacts with the enol tautomeric form 153 of pyrazolone 152 to give ninhydrin-substituted pyrazoles 151 in a three-component reaction, as depicted in Scheme 52 [158]. The two-component formation of pyrazolone 156 from acetylenedicarboxylates and phenylhydrazine

Development of a flow photochemical process for a π-Lewis acidic metal-catalyzed cyclization/radical addition sequence: in situ-generated 2-benzopyrylium as photoredox catalyst and reactive intermediate

• Masahiro Terada,
• Zen Iwasaki,
• Ryohei Yazaki,
• Shigenobu Umemiya and
• Jun Kikuchi

Beilstein J. Org. Chem. 2024, 20, 1973–1980, doi:10.3762/bjoc.20.173

• feature of this sequential transformation is that the in situ-generated 2-benzopyrylium intermediates A are used not only as an electrophile but also as a photoredox catalyst. However, as this reaction is carried out under relatively harsh conditions (i.e., light irradiation, use of an excess amount of

Radical reactivity of antiaromatic Ni(II) norcorroles with azo radical initiators

• Siham Asyiqin Shafie,
• Ryo Nozawa,
• Hideaki Takano and
• Hiroshi Shinokubo

Beilstein J. Org. Chem. 2024, 20, 1967–1972, doi:10.3762/bjoc.20.172

• the electrophile [16][17][18]. In addition, C–C double bonds of the norcorrole skeleton outside the π-delocalization pathway exhibit a reactivity similar to an alkene to afford hydrogenated norcorroles by hydrogenation [19] or reduction with hydrazine [20] and [3 + 2]-cycloadducts with 1,3-dipoles [21

Regioselective alkylation of a versatile indazole: Electrophile scope and mechanistic insights from density functional theory calculations

• Pengcheng Lu,
• Luis Juarez,
• Paul A. Wiget,
• Weihe Zhang,
• Krishnan Raman and
• Pravin L. Kotian

Beilstein J. Org. Chem. 2024, 20, 1940–1954, doi:10.3762/bjoc.20.170

• reactions with compound 6 afforded the N1-substituted indazole analogs 15a–q with excellent yields (>90%), except for 15m, which failed to form after multiple attempts likely due to an instability of the electrophile 14m under optimized conditions (conditions A: 1.5 equiv tosylate, 1.0 equiv 6, 2.0 equiv

A new platform for the synthesis of diketopyrrolopyrrole derivatives via nucleophilic aromatic substitution reactions

• Vitor A. S. Almodovar and
• Augusto C. Tomé

Beilstein J. Org. Chem. 2024, 20, 1933–1939, doi:10.3762/bjoc.20.169

• generating new DPP derivatives through nucleophilic aromatic substitution reactions with thiols and phenols. The main objective of this study was to employ the N,N’-bis(pentafluorobenzyl)-DPP 2 as an electrophile and investigate its reactivity with thiols and phenols (Scheme 1). All SNAr reactions were

The Groebke–Blackburn–Bienaymé reaction in its maturity: innovation and improvements since its 21st birthday (2019–2023)

• Cristina Martini,
• Muhammad Idham Darussalam Mardjan and
• Andrea Basso

Beilstein J. Org. Chem. 2024, 20, 1839–1879, doi:10.3762/bjoc.20.162

• reaction can be considered the third in importance after Ugi [3] and Passerini [4] ones, and, as the two venerable reactions, is an α-addition of an electrophile and a nucleophile to an isocyanide, followed by a suitable rearrangement, as depicted in Scheme 1. Compared with the Passerini and Ugi reactions

• its nucleophilicity and improving its orientation. Furthermore, Ser105 formed a strong hydrogen bond also with benzaldehyde, making it a better electron acceptor. Interestingly, also the imine intermediate showed strong interaction with Thr40 and Ser105 residues, so becoming a good electrophile for

Divergent role of PIDA and PIFA in the AlX₃ (X = Cl, Br) halogenation of 2-naphthol: a mechanistic study

• Kevin A. Juárez-Ornelas,
• Manuel Solís-Hernández,
• Pedro Navarro-Santos,
• J. Oscar C. Jiménez-Halla and
• César R. Solorio-Alvarado

Beilstein J. Org. Chem. 2024, 20, 1580–1589, doi:10.3762/bjoc.20.141

• generated in situ simply by mixing PIFA with a Lewis acid, in this case AlCl3. The importance of this protocol arises from the oxidation of an AlCl3-based chlorine atom, which is an available and cheap reagent. Then it is used as an electrophile source in the chlorination process with an umpolung reactivity