Synthesis of N-acetyl diazocine derivatives via cross-coupling reaction

• Thomas Brandt,
• Pascal Lentes,
• Jeremy Rudtke,
• Michael Hösgen,
• Christian Näther and
• Rainer Herges

Beilstein J. Org. Chem. 2025, 21, 490–499, doi:10.3762/bjoc.21.36

• switching efficiency in aqueous solutions. In order to investigate the chemistry of this promising photoswitch and to unlock further applications, we now investigate strategies for the synthesis of derivatives, which are based on cross-coupling reactions. Fourteen vinyl-, aryl-, cyano-, and amino

• provides good yields of 65% and 71%, respectively, for the vinyl N-acetyl diazocine 8 (Table 3). An alternative way of vinylating N-acetyl diazocines is the Pd-catalyzed vinylation with polyvinylsiloxanes and TBAF as activating agent following the method by Denmark et al. giving rise to even higher yields

Synthesis of disulfides and 3-sulfenylchromones from sodium sulfinates catalyzed by TBAI

• Zhenlei Zhang,
• Ying Wang,
• Xingxing Pan,
• Manqi Zhang,
• Wei Zhao,
• Meng Li and
• Hao Zhang

Beilstein J. Org. Chem. 2025, 21, 253–261, doi:10.3762/bjoc.21.17

• which the thiosulfonate was cleaved and then dimerized to form the disulfide. The reaction of sodium p-toluenesulfinate and styrene resulted in the generation of the corresponding vinyl sulfone (Scheme 5, reaction 2), suggesting the formation of p-toluenesulfonyl iodide during the reaction [50][51

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

• copper catalyst, providing the vinyl copper intermediate INT-30. This intermediate then undergoes oxidative addition to the N–O bond of the dioxazolone to generate INT-31. Subsequently, decarboxylative reductive elimination occurs, forming the copper imidate INT-32. The active copper species is

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

• (II)–N3 complex 60. The azidyl radical 62 then reacts with N-arylenamine 57 via radical addition. Thereafter, it undergoes oxidation to form a kinetically labile vinyl azide intermediate 64. This vinyl azide intermediate 64 dissociates, yielding Cu(II) iminyl complex 65 via denitrogenation

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

• corresponding saturated compounds. Subsequent nucleophilic addition of the cyclic vinyl ether to the iminium salt generates an intermediate XXI susceptible of intramolecular electrophilic attack to give a tricyclic structure XXII. The final deprotonation provides the desired product 24. The multicomponent

• of α-substituted propargylamines 10. Synthesis of N-propargylcarbamates 11. Synthesis of (E)-vinyl sulfones 12. Synthesis of o-halo-substituted aryl chalcogenides 13. Synthesis of α-aminophosphonates 14. Synthesis of unsaturated furanones and pyranones 15–17. Synthesis of substituted

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

Emerging trends in the optimization of organic synthesis through high-throughput tools and machine learning

• Pablo Quijano Velasco,
• Kedar Hippalgaonkar and
• Balamurugan Ramalingam

Beilstein J. Org. Chem. 2025, 21, 10–38, doi:10.3762/bjoc.21.3

• , utilizing a custom Python package developed in-house [53]. This approach enabled us to track the conversion process at different residence times. Specifically, we quantified the conversion by analyzing the area under the curve (AUC) of the Raman-active vibrational modes associated with the styrene–vinyl C=C

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

• different electronic properties (18, 25–41, Figure 6) were screened as catalysts for the sulfa-Michael addition of tert-butyl benzylmercaptan 42 to phenyl vinyl sulfone (43). Without the addition of a porphyrin, no product was formed. Among the non-alkylated porphyrins (18, 25–32) only the ones containing

Cyclodextrin-based rotaxanes for polymer materials: challenge on simultaneous realization of inexpensive production and defined structures

• Yosuke Akae

Beilstein J. Org. Chem. 2024, 20, 3026–3049, doi:10.3762/bjoc.20.252

• a major content of the material, Takata and co-workers developed the rotaxane crosslinker, which can be integrated as a small content on vinyl polymer synthesis to afford vinyl polymers having a certain domain of polyrotaxane crosslinking points (Figure 14) [84]. In this system, the crosslinker was

• synthesized and exhibited a rotaxane crosslinking nature; hence, the resulting vinyl polymer, e.g., polyDMAAm crosslinked by VSC, showed enhanced stretchability induced by rotaxane crosslinking. Moreover, when it was applied to a thermo-responsive polymer like poly(N-isopropyl acrylamide) (NIPAM), the thermo

• -responsive nature became much faster than the system without VSC. This fast responsiveness was induced by the dynamic rotaxane crosslinking structure. This method can be applied in various vinyl polymer systems, and induces the rotaxane crosslinking nature to the resulting network polymer, suggesting its

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

• configuration of the double bond was confirmed using 1H,1H-NOESY spectroscopy. As shown in Figure 2, a correlation between protons of the allyl moiety and the aryl substituent evidenced their spatial proximity in molecule 1c. The absence of a correlation between allyl and vinyl protons additionally supported

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

• , C–C bond formation was reported by Chen and colleagues in 2020 via the arylation of vinyl pinacol boronates 23 by using diaryliodonium salts 16 to yield trans-arylvinylboronates 24 in the absence of a metal catalyst [62]. The optimized reaction conditions involve the reaction of substituted

• diaryliodonium salts 16 with different substituted vinyl pinacol boronates 23 in dichloromethane as solvent at 100 °C in a sealed tube in the presence of a wet inorganic base (Scheme 8). Both K2CO3 and Li2CO3 were found to be compatible with the reaction, and it was observed that no product was obtained in the

• , 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

Synthesis of tricarbonylated propargylamine and conversion to 2,5-disubstituted oxazole-4-carboxylates

• Kento Iwai,
• Akari Hikasa,
• Kotaro Yoshioka,
• Shinki Tani,
• Kazuto Umezu and
• Nagatoshi Nishiwaki

Beilstein J. Org. Chem. 2024, 20, 2827–2833, doi:10.3762/bjoc.20.238

• phenacyl group, yielding 9 without any detectable cyclization product (Scheme 4). This hydration process is thought to proceed via two paths. The reaction is initiated by the protonation of the ethynyl group to generate the vinyl cation intermediate 10. Product 9 is directly formed by the attack of a water

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

• expand the scope of transition metal-catalyzed substitution reactions. Since its discovery in 2022, copper-catalyzed yne-allylic substitution has undergone rapid development and significant progress has been made using the key copper vinyl allenylidene intermediates. This review summarizes the

• 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

• substitution has emerged as a new and robust approach to achieve formal allylic substitution using stabilized nucleophiles. The copper acetylide-bonded allylic cation with copper vinyl allenylidene species as its resonance structure is key for the process, which can achieve the outer-sphere attack of

Synthesis of fluoroalkenes and fluoroenynes via cross-coupling reactions using novel multihalogenated vinyl ethers

• Yukiko Karuo,
• Keita Hirata,
• Atsushi Tarui,
• Kazuyuki Sato,
• Kentaro Kawai and
• Masaaki Omote

Beilstein J. Org. Chem. 2024, 20, 2691–2703, doi:10.3762/bjoc.20.226

• fluorovinyl ethers, which contains a reactive bromine atom, to afford a series of fluoroalkenes and fluoroenynes in moderate to high yields. Keywords: fluoroalkenes; fluoroenynes; multihalogenated vinyl ethers; Suzuki–Miyaura cross-coupling reactions; Sonogashira cross-coupling reactions; Introduction

• development of a dual-reactive fluorine-containing C2-unit, which was prepared from trifluoroethanol in two steps in 63% yield, allowed the convergent synthesis of fluoroalkenes (Scheme 1C) [26]. We recently found multihalogenated vinyl ethers 1 could be obtained by the reaction of phenols with 2-bromo-2

• First, we optimized the conditions of the Suzuki–Miyaura cross-coupling in reference to the report by Yang et al. (Table 1) [43]. Upon the treatment of multihalogenated vinyl ether 1a with phenylboronic acid 4a (1.3 equiv) and palladium diacetate (10 mol %) as a catalyst at 40 °C, Suzuki–Miyaura cross

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

• agrochemical and pharmaceutical chemistry. In 2019, Jiao and colleagues reported that 1,2-dichloroethane (DCE) could be used as a chlorination reagent for the production of (hetero)aryl chlorides and vinyl chlorides [21]. The reactions were carried out in an undivided cell containing a mixture of DCE in

Asymmetric organocatalytic synthesis of chiral homoallylic amines

• Nikolay S. Kondratyev and
• Andrei V. Malkov

Beilstein J. Org. Chem. 2024, 20, 2349–2377, doi:10.3762/bjoc.20.201

• excellent enantioselectivities (89–98% ee) and low to moderate yields (48–72%). The homologation step proceeds via the stereoretentive 1,2-migration of the vinyl group from the tetracoordinated boron to the highly electrophilic carbon of the diazomethane, concerted with the elimination of the nitrogen

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

• observed when AQ-3 was applied. Besides, the modifications of the quinuclidine ring through replacing the vinyl substituent in the parent quinine core by a triple bond (AQ-5) led to no substantial improvement in the mixer mill, but the decrease of enantioselectivity in the reaction performed in the

gem-Difluorination of carbon–carbon triple bonds using Brønsted acid/Bu₄NBF₄ or electrogenerated acid

• Mizuki Yamaguchi,
• Hiroki Shimao,
• Kengo Hamasaki,
• Keiji Nishiwaki,
• Shigenori Kashimura and
• Kouichi Matsumoto

Beilstein J. Org. Chem. 2024, 20, 2261–2269, doi:10.3762/bjoc.20.194

• the use of HF or its complexes as a reagent. These reactions seem to proceed via the formation of the vinyl fluoride as the intermediate [25][26][27][28]. In the first example, Olah and co-workers reported the reaction of terminal alkynes with HF/pyridine (Olah reagent) (Figure 1, reaction 1) [29][30

Metal-free double azide addition to strained alkynes of an octadehydrodibenzo[12]annulene derivative with electron-withdrawing substituents

• Naoki Takeda,
• Shuichi Akasaka,
• Susumu Kawauchi and
• Tsuyoshi Michinobu

Beilstein J. Org. Chem. 2024, 20, 2234–2241, doi:10.3762/bjoc.20.191

• the strain-promoted double azide addition feature, DBA 5 was evaluated as a crosslinker for azidated polymers. After 5 (5 mol %) was added to a partially azidated poly(vinyl chloride) (PVC-N3) (x = 0.11, n = 1000) in THF, the solvent was gradually evaporated on a Teflon boat. The resulting self

• metal-free click reaction was employed to crosslink a partially azidated poly(vinyl chloride). The crosslinking proceeded by simply mixing the polymer and crosslinker in THF and evaporating, and the formation of the crosslinked polymer film was confirmed by the strain–stress curves. The developed method

• partially azidated poly(vinyl chloride) (PVA-N3) was prepared by stirring poly(vinyl chloride) and NaN3 in DMF at room temperature overnight. Measurements NMR spectra were recorded using a JEOL mode Al300 (300 MHz) at room temperature. Deuterated chloroform was used as the solvent unless otherwise stated

Efficacy of radical reactions of isocyanides with heteroatom radicals in organic synthesis

• Akiya Ogawa and
• Yuki Yamamoto

Beilstein J. Org. Chem. 2024, 20, 2114–2128, doi:10.3762/bjoc.20.182

• generates a stannylated imidoyl radical 20. The subsequent 5-exo cyclization, hydrogen abstraction from n-Bu3SnH, and aromatization successfully afforded the stannylated indole derivative 21 (Scheme 13) [8][54][55][56]. The stannyl group of 21 could be transferred to aryl or vinyl group by cross-coupling

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

• vinyl ether enables the synthesis of 3-alkoxyalkenones 74, presenting an elegant route. Subsequently, these compounds undergo a three-component reaction with various hydrazines, forming 1,3-substituted pyrazoles 75 (Scheme 26) [104]. However, one limitation is the formation of 1,5-substituted pyrazoles

• pyrazole starting materials from isonitriles 158, dialkyl acetylenedicarboxylate 147, and hydrazine carboxamide 159. The addition of the isonitrile to the Michael system yields a nitrilium-vinyl anion zwitterion 161, that is protonated by the hydrazine carboxamide, which undergoes addition to furnish the

• toluene [173]. N-Vinylimidazole, an alkene with a leaving group, was used to synthesize the 3-substituted pyrazoles 169 because, unlike acetylene, it is not gaseous and, therefore, easier to handle. Instead of vinylimidazole, vinyl azides 170 can also be used as alkyne surrogates. After the 1,3-dipolar

Diastereoselective synthesis of highly substituted cyclohexanones and tetrahydrochromene-4-ones via conjugate addition of curcumins to arylidenemalonates

• Deepa Nair,
• Abhishek Tiwari,
• Banamali Laha and
• Irishi N. N. Namboothiri

Beilstein J. Org. Chem. 2024, 20, 2016–2023, doi:10.3762/bjoc.20.177

• reactions, especially as a Michael donor at the central methylene carbon, and Michael acceptor at the enone vinyl carbon. Therefore, it would be interesting to develop novel methodologies using curcumin and its non-natural analogs as key starting materials [24]. Because of its multifaceted reactive site

1,2-Difluoroethylene (HFO-1132): synthesis and chemistry

• Liubov V. Sokolenko,
• Taras M. Sokolenko and
• Yurii L. Yagupolskii

Beilstein J. Org. Chem. 2024, 20, 1955–1966, doi:10.3762/bjoc.20.171

• synthesis of 1,2-difluoroethylene based on perfluoropropyl vinyl ether as starting material can be found (Scheme 7). Consequently, two methods to prepare 1,2-difluoroethylene in the laboratory have been described to date. Even though at least five approaches to HFO-1132 can be found in patent literature, it

• -difluoroethylene and the disappearance of vinyl protons resonances in the 1H NMR spectra [78]. Addition to the C=C bond Halogen addition: 1,2-Difluoroethylene was reported to react with chlorine [46][79] and bromine [51] under irradiation, yielding 1,2-difluoro-1,2-dihaloethanes in moderate to high yield (Scheme 9

• silane that was obtained was pyrolyzed to form vinyl fluoride. It was shown that SF5Br easily reacted with the E- and Z-isomer, respectively, of 1,2-difluoroethylene in the presence or absence of light, yielding a mixture of erythro- and threo-isomeric addition products in both cases (Scheme 14) [92

Ugi bisamides based on pyrrolyl-β-chlorovinylaldehyde and their unusual transformations

• Alexander V. Tsygankov,
• Vladyslav O. Vereshchak,
• Tetiana O. Savluk,
• Serhiy M. Desenko,
• Valeriia V. Ananieva,
• Oleksandr V. Buravov,
• Yana I. Sakhno,
• Svitlana V. Shishkina and
• Valentyn A. Chebanov

Beilstein J. Org. Chem. 2024, 20, 1773–1784, doi:10.3762/bjoc.20.156

• heterylidenepyruvic acid. An optimized synthetic protocol for this transformation was elaborated and a plausible sequence involving the elimination of the 2-chloroacetamide moiety and the conversion of the β-chlorovinyl fragment into a vinyl one is provided. Keywords: convertible isocyanides; multicomponent reaction

• of acid also led to the formation of amides 10b–d as main products and the corresponding ketobisamides 12d–e as minor products (Table 2, entries 10, 11, 18, 23, and 24). This can be explained by the formation of HCl in the reaction mixture due to the substitution of chlorine in the vinyl chloride

• conversion of the β-chlorovinyl fragment into a vinyl fragment giving rise to ethyl (E)-4-(4-(R1-amino)-3,4-dioxobut-1-en-1-yl)-3,5-dimethyl-1H-pyrrole-2-carboxylates. Another direction of the post-transformation was the replacement of the chlorine atom in the β-chlorovinyl group of the Ugi bisamides with a

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

• detected as a side reaction via mass spectrometry. Vinyl alcohols were also studied, giving carvone (4v) in 74% yield without oxidation of the double bonds. Finally, other heterocyclic benzylic alcohols were investigated, which led to undesired chlorinations in the case of benzimidazoles 3w and 3x and