Advances in radical peroxidation with hydroperoxides

• Oleg V. Bityukov,
• Pavel Yu. Serdyuchenko,
• Andrey S. Kirillov,
• Gennady I. Nikishin,
• Vera A. Vil’ and
• Alexander O. Terent’ev

Beilstein J. Org. Chem. 2024, 20, 2959–3006, doi:10.3762/bjoc.20.249

• of allylic peroxidation 2, 4 and 5 were observed (Scheme 4) [24]. Similar transformations were reported later using CuCl as the catalyst [39]. Later, Gade with coauthors demonstrated the allylic peroxidation of cyclohexane with TBHP using the alkylperoxocobalt(III) complexes [Co(BPI)(OAc)(OO-t-Bu

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

• Poznań, Poland 10.3762/bjoc.20.247 Abstract The incorporation of fluorine atoms within the structure of organic compounds is known to exert a significant impact on their electronic properties, thereby modulating their reactivity in diverse chemical transformations. In the context of our investigation

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

• various useful transformations under mild, eco-friendly reaction conditions [4][5][6][7][8][9][10][11]. Various review articles [12][13][14][15][16][17][18][19][20][21][22][23][24][25][26] and books [27][28] have appeared on the chemistry of hypervalent iodine compounds. In the past two decades

• capability to function as radical initiators. The use of diaryliodonium salts as efficient electrophilic arylating reagents in a wide range of organic transformations is due to their unique features such as solid-state nature, excellent stability, and the presence of a robust leaving group [39][40][41][42

• reductive elimination to produce the desired sulfilimine 99 (Scheme 40) [92]. Synthesizing S-aryl xanthates through transition-metal-catalyzed or SNAr reactions presents challenges due to potential additional transformations occurring under the reaction conditions. However, employing diaryliodonium salts

C–H Trifluoromethylthiolation of aldehyde hydrazones

• Victor Levet,
• Balu Ramesh,
• Congyang Wang and
• Tatiana Besset

Beilstein J. Org. Chem. 2024, 20, 2883–2890, doi:10.3762/bjoc.20.242

• . Various reagents and chemical transformations have been elaborated in this context over the years [21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37][38][39][40][41][42][43][44][45][46][47][48][49][50][51]. Despite these recent advances, the design of highly functionalized

• various transformations [54][55][56][57][58][59][60][61][62][63][64]. In consequence, a large number of transition-metal-catalyzed or radical-mediated processes for C–H functionalization of aldehyde hydrazones has flourished over the years. An ideal scenario for a direct and sustainable synthetic route

• towards trifluoromethylthiolated hydrazones will be the direct C–H functionalization of the corresponding aldehyde hydrazone, an uncharted transformation to date. Forging a C–S bond by the direct C–H-bond functionalization of hydrazones is still underdeveloped. Except for transformations leading to the

Mechanochemical difluoromethylations of ketones

• Jinbo Ke,
• Pit van Bonn and
• Carsten Bolm

Beilstein J. Org. Chem. 2024, 20, 2799–2805, doi:10.3762/bjoc.20.235

• and 1n were studied. Both gave the expected products in yields of 50% (for 3m) and 44% (for 3n). Besides these successful transformations several ketones proved unsuitable (Scheme S1 in Supporting Information File 1). Additionally, attempted [4 + 1]-type cycloadditions of three 1-arylprop-2-en-1-ones

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

Base-promoted cascade recyclization of allomaltol derivatives containing an amide fragment into substituted 3-(1-hydroxyethylidene)tetronic acids

• Andrey N. Komogortsev,
• Constantine V. Milyutin and
• Boris V. Lichitsky

Beilstein J. Org. Chem. 2024, 20, 2585–2591, doi:10.3762/bjoc.20.217

• purification. The synthetic utility of the prepared tetronic acids was demonstrated by further transformations at the hydroxyethylidene fragment. The structures of one obtained tetronic acid and one product of derivatization were confirmed by X-ray analysis. Keywords: allomaltol; base-promoted recyclization

• -hydroxypyran-4-ones these products are widely used in organic synthesis [17][18][19][20][21][22][23]. Among the diverse chemical transformations of allomaltol derivatives the recyclizations of the pyranone ring are of great interest. As a rule, such reactions are realized under action of nitrogen-containing

• nucleophiles and open access to a large array of substituted pyridin-4-ones. Various conditions and reagents employed for these transformations are presented in numerous papers [24][25][26][27][28][29]. Besides that, approaches to the synthesis of pyridazinones and pyrazoles based on the interaction of 3

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

• electrochemical transformations. Detailed reaction conditions, such as electrolyte, electrode material, and the use of constant current or constant voltage, are presented. Additionally, we discuss the mechanisms of some representative reactions and provide selected examples of LSF of relevant bioactive compounds

• arenes via palladium-catalyzed electrooxidation, further showcasing the versatility and potential of this approach in organic synthesis (Scheme 42b) [58]. These methodologies underline the expanding role of palladium catalysis in electrochemical transformations, offering robust strategies for the

• into a carbon radical intermediate. The photocatalyst then oxidizes this intermediate, leading to the final product (Scheme 45). This approach underscores the significant potential of combining electro- and photocatalysis to achieve selective and mild transformations in organic synthesis, particularly

Visible-light-mediated flow protocol for Achmatowicz rearrangement

• Joachyutharayalu Oja,
• Sanjeev Kumar and
• Srihari Pabbaraja

Beilstein J. Org. Chem. 2024, 20, 2493–2499, doi:10.3762/bjoc.20.213

• transformations, then reaction extraction and separation, into a single process, which are typically performed individually/separately in batch methods. This enhances the overall efficiency for obtaining the desired product(s) from the reaction mixture. In continuation to our efforts on developing flow-based

Machine learning-guided strategies for reaction conditions design and optimization

• Lung-Yi Chen and
• Yi-Pei Li

Beilstein J. Org. Chem. 2024, 20, 2476–2492, doi:10.3762/bjoc.20.212

• al. [156]. Moreover, it is unclear whether AAM significantly improves the accuracy of reaction modeling. The AAM-required methods are usually tested on specific reaction types, where the reaction transformations and AAM are clear and correct. However, most large-scale reaction datasets do not have

• related literature, caution is advised as experimental apparatus from different sources could introduce systematic errors in reported yields [46]. Furthermore, BO cannot generalize well from past reactions to unseen reaction transformations, which inherently requires gathering new relevant data for new

Phenylseleno trifluoromethoxylation of alkenes

• Clément Delobel,
• Armen Panossian,
• Gilles Hanquet,
• Frédéric R. Leroux,
• Fabien Toulgoat and
• Thierry Billard

Beilstein J. Org. Chem. 2024, 20, 2434–2441, doi:10.3762/bjoc.20.207

• finally be reopened by trifluoroacetate (Scheme 3). Although the selenylated compounds 2 are of interest, the presence of the PhSe moiety allows other transformations to be considered. First, the oxidative elimination of the selenyl moiety to generate a double bond was first studied. However, regardless

Synthesis, electrochemical properties, and antioxidant activity of sterically hindered catechols with 1,3,4-oxadiazole, 1,2,4-triazole, thiazole or pyridine fragments

• Daria A. Burmistrova,
• Andrey Galustyan,
• Nadezhda P. Pomortseva,
• Kristina D. Pashaeva,
• Maxim V. Arsenyev,
• Oleg P. Demidov,
• Mikhail A. Kiskin,
• Andrey I. Poddel’sky,
• Nadezhda T. Berberova and
• Ivan V. Smolyaninov

Beilstein J. Org. Chem. 2024, 20, 2378–2391, doi:10.3762/bjoc.20.202

• : antioxidant activity; catechol thioethers; heterocycles; redox-transformations; thiones; Introduction Synthetic derivatives of polyphenols, in particular catechol (hydroquinone), represent a promising group of pharmacologically active substances [1][2]. Catechol-containing compounds demonstrate

• [25]. A feature of mercapto-substituted heterocycles is the possibility of their existence in two tautomeric forms: thiol or thione [26][27]. The ability to tautomeric transformations affects their biological activity and allows the use of these molecular blocks to design compounds with different

• (control) during the incubation for 3, 24, and 48 hours (concentration of compounds in the reaction medium is 0.1 mM). The results are expressed as mean ± standard deviation (* p < 0.001; ** p < 0.01; ***p < 0.05). Synthesis of catechol-containing compounds 1–9. Electrochemical transformations of compounds

Tandem diazotization/cyclization approach for the synthesis of a fused 1,2,3-triazinone-furazan/furoxan heterocyclic system

• Yuri A. Sidunets,
• Valeriya G. Melekhina and
• Leonid L. Fershtat

Beilstein J. Org. Chem. 2024, 20, 2342–2348, doi:10.3762/bjoc.20.200

• , whether isolated or generated in situ, may undergo various controlled transformations [42]. However, previously, we failed to introduce amino-1,2,5-oxadiazoles bearing an amide functionality into the diazotization protocol, arguably due to an increased electron-withdrawing effect and elevated instability

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

• ][7][8]. Furthermore, the integration of mechanochemistry and organocatalysis leads to the development of more sustainable transformations, characterized by reduced reaction times, decreased catalyst loadings, and significantly diminished solvent usage and waste production [9][10][11]. The pioneering

• studies by Bolm [12][13], and Juaristi et al. [14]. have significantly advanced chiral secondary amine-catalyzed stereoselective reactions under ball milling conditions, representing a widely explored activation mode in mechanochemical-mediated transformations. However, reports on chiral primary iminium

• [15][16] or iminium-ion catalysis [17] under ball-mill conditions are scarce, in contrast to the abundance of transformations catalyzed by such covalent catalysis. Among the numerous organocatalytic reactions facilitated by primary amine-based iminium ions, Michael-type additions deserve special

Hydrogen-bond activation enables aziridination of unactivated olefins with simple iminoiodinanes

• Phong Thai,
• Lauv Patel,
• Diyasha Manna and
• David C. Powers

Beilstein J. Org. Chem. 2024, 20, 2305–2312, doi:10.3762/bjoc.20.197

• ), Koser’s reagent (PhI(OH)OTs), Zhdankin’s reagent (C6H4(o-COO)IN3, ABX), and Dess–Martin periodinane (DMP) – and find application in an array of synthetically important transformations including olefin difunctionalization, carbonyl desaturation, alcohol oxidation, and C–H functionalization [3][4

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

• transformations. Subsequently, we review ML employed for privileged catalysts, before focusing on its application for catalyst and reaction design. Concluding, we give our view on current challenges and future directions for this field, drawing inspiration from the application of ML to other scientific domains

• catalysts [3]. In particular, enantioselective organocatalysis has shown an impressive rise in the last decades, owing to the tunability of catalysts and different modes of activation, enabling a manifold of different transformations [4][5]. The development of the field, driven by many researchers, led to

• the award of the Nobel Prize to List and MacMillan in 2021 ‘for the development of asymmetric organocatalysis’. Organocatalytic transformations have also seen the transition to industrial processes for the production of a variety of pesticides and medicinal compounds, as recently reviewed [6][7][8][9

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

• blocks for further transformations. We have focused on the investigation of gem-difluorination of carbon–carbon triple bonds, because this procedure is one of the most simple but powerful and straightforward methods. In addition, there have been a few reports in the literature that seem to mainly rely on

Natural resorcylic lactones derived from alternariol

• Joachim Podlech

Beilstein J. Org. Chem. 2024, 20, 2171–2207, doi:10.3762/bjoc.20.187

• cleavage and further transformations. The isomeric altenusinoides A and B (52 and 53) were isolated from Alternaria sp., where no biological activities were determined so far for these compounds [242]. Altenuene and its diastereomers and substituted derivatives Altenuene and its diastereomers: Altenuene

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

• on molecular transformations by the reactions of heteroatom radicals with isocyanides using methods 1 and 2. Thus, in this perspective, we mainly focused on the use of method 1 and method 2 for the generation of heteroatom radicals and the reactivity of them with isocyanides. Among these three

From perfluoroalkyl aryl sulfoxides to ortho thioethers

• Yang Li,
• Guillaume Dagousset,
• Emmanuel Magnier and
• Bruce Pégot

Beilstein J. Org. Chem. 2024, 20, 2108–2113, doi:10.3762/bjoc.20.181

• , sigmatropic rearrangements have established themselves as robust and versatile tools for many transformations in organic synthesis [1][2][3]. They were widely employed with a wide range of substrates. With a peculiar type of scaffold, S-perfluoroalkyl aryl sulfoxides, in 2009, we were the first to demonstrate

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

Harnessing the versatility of hydrazones through electrosynthetic oxidative transformations

• Aurélie Claraz

Beilstein J. Org. Chem. 2024, 20, 1988–2004, doi:10.3762/bjoc.20.175

• construction of valuable compounds. Electrooxidative transformations of hydrazones constitute an attractive opportunity to take advantage of the versatility of these reagents. By directly harnessing the electrical current to perform the oxidative process, a large panel of organic molecules can be accessed from

• readily available hydrazones under mild, safe and oxidant-free reaction conditions. This review presents a comprehensive overview of oxidative electrosynthetic transformations of hydrazones. It includes the construction of azacycles, the C(sp2)−H functionalization of aldehyde-derived hydrazones and the

• hydrazones can act as radical acceptors for the synthesis of functionalized amines or hydrazones through reductive functionalization [21][25][26] or oxidative C(sp2)–H functionalization [27][28], respectively. Consequently, given their rich reactivity profile, exploring new synthetic transformations of

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

• employed as nucleophiles in chemical transformations, and a mixture of both N1- and N2-alkylated products is formed, depending on the reaction conditions, with little selectivity in regards to substituent effects [27][28][29][30][31][32][33]. Considering the importance of indazoles as a widely used

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

• or novel properties can be prepared by conventional chemical modifications of simple DPP derivatives [3][18]. The most frequently used transformations include: i) N-alkylation with adequately functionalized alkyl groups [19][20][21][22], ii) N-arylation [23][24][25], and functionalization at the 3,6

• purposes. This study not only contributes to the expansion of accessible N-substituted DPP derivatives but also reveals that such transformations can be achieved with outstanding efficiency and environmental sensitivity by employing mild reaction conditions. Experimental Chemicals and instrumentation The

Novel oxidative routes to N-arylpyridoindazolium salts

• Oleg A. Levitskiy,
• Yuri K. Grishin and
• Tatiana V. Magdesieva

Beilstein J. Org. Chem. 2024, 20, 1906–1913, doi:10.3762/bjoc.20.166

• [13][14][15][16][17][18][19], N,N-diarylbenzidines [20][21], N,N-diaryldihydrophenazines [20][21] and some others. Therefore, the selectivity issue is of primary importance. The guidelines for prediction of the dominant reaction path in the competing oxidative transformations of variously substituted