Transformation of the cyclohexane ring to the cyclopentane fragment of biologically active compounds

• Natalya Akhmetdinova,
• Ilgiz Biktagirov and
• Liliya Kh. Faizullina

Beilstein J. Org. Chem. 2025, 21, 2416–2446, doi:10.3762/bjoc.21.185

• to acid 157 by UV-C, which occurred only in the presence of water (Scheme 29). In the work [83], it is shown that a vinylogous Norrish Type II cascade reaction can occur for unsaturated ketones substituted with cyclopropanes. Interesting results of photochemical ring contraction were described by

An Fe(II)-catalyzed synthesis of spiro[indoline-3,2'-pyrrolidine] derivatives

• Elizaveta V. Gradova,
• Nikita A. Ozhegov,
• Roman O. Shcherbakov,
• Alexander G. Tkachenko,
• Larisa Y. Nesterova,
• Elena Y. Mendogralo and
• Maxim G. Uchuskin

Beilstein J. Org. Chem. 2025, 21, 2383–2388, doi:10.3762/bjoc.21.183

• in high yields (Scheme 1, path c) [10]. Further expanding the scope of enantioselective approaches, a Michael/cyclization cascade reaction between 3-aminooxindoles and 2-enoylpyridines, catalyzed by a cinchonidine-based thiourea organocatalyst, was developed. Subsequent treatment with HCl in methanol

Comparative analysis of complanadine A total syntheses

• Reem Al-Ahmad and
• Mingji Dai

Beilstein J. Org. Chem. 2025, 21, 2334–2344, doi:10.3762/bjoc.21.178

• finding highlights the importance of complanadine A’s pseudo-dimeric structural motif for its biological function. The Sarpong total synthesis – 2010 In the same year (2010), Sarpong and co-workers reported their total synthesis of complanadine A (Scheme 3). Their synthesis features a biomimetic cascade

• reaction to rapidly establish the tetracyclic skeleton of complanadine A and an iridium-catalyzed site-selective pyridine C–H borylation followed by a Suzuki–Miyaura cross coupling to forge the C2–C3’ linkage. Their synthesis achieves a high degree of synergy between classic transformations and modern

C2 to C6 biobased carbonyl platforms for fine chemistry

• Jingjing Jiang,
• Muhammad Noman Haider Tariq,
• Florence Popowycz,
• Yanlong Gu and
• Yves Queneau

Beilstein J. Org. Chem. 2025, 21, 2103–2172, doi:10.3762/bjoc.21.165

The application of desymmetric enantioselective reduction of cyclic 1,3-dicarbonyl compounds in the total synthesis of terpenoid and alkaloid natural products

• Dong-Xing Tan and
• Fu-She Han

Beilstein J. Org. Chem. 2025, 21, 2085–2102, doi:10.3762/bjoc.21.164

• transformations of 121 generated bromodiene 122. Next, the metal–halogen exchange/intermolecular addition of 122 with aldehyde (+)-123 and in situ PtCl2-promoted hydrolysis and hydration gave tricyclic product 124. The BnMe3NOH-mediated intramolecular Michael/aldol cascade reaction of 124 constructed the C/D

Further elaboration of the stereodivergent approach to chaetominine-type alkaloids: synthesis of the reported structures of aspera chaetominines A and B and revised structure of aspera chaetominine B

• Jin-Fang Lü,
• Jiang-Feng Wu,
• Jian-Liang Ye and
• Pei-Qiang Huang

Beilstein J. Org. Chem. 2025, 21, 2072–2081, doi:10.3762/bjoc.21.162

• synthesis of (–)-isochaetominine A was increased from 25.4% to 30.8% over five steps. Secondly, a new protocol featuring the use of an aged solution of K2CO3/MeOH to quench the DMDO epoxidation-triggered cascade reaction was developed, which allowed the in situ selective mono- or double epimerization at C11

Bioinspired total syntheses of natural products: a personal adventure

• Zhengyi Qin,
• Yuting Yang,
• Nuran Yan,
• Xinyu Liang,
• Zhiyu Zhang,
• Yaxuan Duan,
• Huilin Li and
• Xuegong She

Beilstein J. Org. Chem. 2025, 21, 2048–2061, doi:10.3762/bjoc.21.160

• reported. A bioinspired approach represents many advantages to bring benefits to total synthesis. It could rapidly achieve complexity of the target molecule from a much simpler precursor in diverse forms of transformations such as cascade reaction, cycloaddition, and C–H functionalization, thereby, shorten

• gymnothespirolignan A in excellent yield and good diastereoselectivity [38] (Scheme 6c). The minor epimer is gymnothespirolignan C, another natural product of this family. This cascade reaction supports the proposed biogenetic pathway of the newly isolated novel siprocyclic gymnothelignans. The bioinspired double

• unprecedented skeleton, we can try to realize how the novel structure is generated in nature from known chiral pool molecules, thus a key cascade reaction to rapidly construct the novel framework would be biosynthetically applicable. This approach has found wide applications in total syntheses of newly-isolated

Aryl iodane-induced cascade arylation–1,2-silyl shift–heterocyclization of propargylsilanes under copper catalysis

• Rasma Kroņkalne,
• Rūdolfs Beļaunieks,
• Armands Sebris,
• Anatoly Mishnev and
• Māris Turks

Beilstein J. Org. Chem. 2025, 21, 1984–1994, doi:10.3762/bjoc.21.154

• techniques, indicating that the observed arylation–cyclization cascade reaction is highly stereospecific. With this result in hand, we performed copper catalyst screening (Table 3). We observed that CuCl and the CuOTf benzene complex gave similarly good yields (82–84% by NMR, Table 3, entries 2 and 4), while

Enantioselective desymmetrization strategy of prochiral 1,3-diols in natural product synthesis

• Lihua Wei,
• Rui Yang,
• Zhifeng Shi and
• Zhiqiang Ma

Beilstein J. Org. Chem. 2025, 21, 1932–1963, doi:10.3762/bjoc.21.151

• , and Et3N in MeCN, the intramolecular Heck/hemiamination cascade reaction of 198 delivered the 5-exo cyclization product 199, simultaneously constructing the fused D and E rings in a single transformation. Three additional steps converted 199 to hydroxy ketone 200, which underwent SmI2-mediated

Oxetanes: formation, reactivity and total syntheses of natural products

• Peter Gabko,
• Martin Kalník and
• Maroš Bella

Beilstein J. Org. Chem. 2025, 21, 1324–1373, doi:10.3762/bjoc.21.101

• performing the reaction under visible light irradiation, or coupling the reaction to other light-induced processes to produce new classes of products. In 2018, Aitken and co-workers reported a synthesis of previously unknown tricyclic 4:4:4 oxetanes 73 through a photochemical triple cascade reaction starting

Recent advances in oxidative radical difunctionalization of N-arylacrylamides enabled by carbon radical reagents

• Jiangfei Chen,
• Yi-Lin Qu,
• Ming Yuan,
• Xiang-Mei Wu,
• Heng-Pei Jiang,
• Ying Fu and
• Shengrong Guo

Beilstein J. Org. Chem. 2025, 21, 1207–1271, doi:10.3762/bjoc.21.98

Gold extraction at the molecular level using α- and β-cyclodextrins

• Susana Santos Braga

Beilstein J. Org. Chem. 2025, 21, 1116–1125, doi:10.3762/bjoc.21.89

• . Reproduced from [52], Resources, Conservation and Recycling, vol. 193, by D. Fang; F. Bi; L. Yang; W. Hu; Z. Hua; H. Wei; C. Chen; Y. Tu; P. Shao; M. Li; X. Luo; G. Yang, “Selective extraction of gold from strong acid e-waste leachate through H+-triggered cascade reaction of thiolated β-cyclodextrin

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

• other hand, Fan and co-workers (2020) prepared α-amidoketone 71 by employing vinyl azide and cinnamic acid (7) in good yield via cascade reaction (Scheme 23B) [58]. The thermal decomposition of the azide led to the generation of the reactive azirine intermediate 72. Moreover, Li and co-workers (2020

• ) employed N-formylpyrrolidine (FPyr) and trichlorotriazine (TCT) to catalyze the amidation of cinnamic acid derivative 121. The reaction proceeds via formation of the reactive acid chloride 36 through cascade reaction involving reactive intermediates 123 and 124 (Scheme 37) [72]. Zeng and co-workers (2019

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

• regulating the chemical selectivity of a three-component radical cascade reaction involving α-brominated aryl ketones 72, olefins 73, and 1-methylquinoxalin-2(1H)-one (74) with an inorganic base, they were able to obtain two important types of products with high yield and enantioselectivity. Through

Chitosan-supported CuI-catalyzed cascade reaction of 2-halobenzoic acids and amidines for the synthesis of quinazolinones

• Xuhong Zhao,
• Weishuang Li,
• Mengli Yang,
• Bojie Li,
• Yaoyao Zhang,
• Lizhen Huang and
• Lei Zhu

Beilstein J. Org. Chem. 2025, 21, 839–844, doi:10.3762/bjoc.21.67

• methods, the cascade reaction between ortho-halogen (e.g., chlorine, bromine or iodine) substituted benzoic acids and amidines has become a prominent route to synthesize the corresponding quinazolinones [10][11][12][13][14][15][16][17][18]. In 2009, Fu and co-workers found that copper(I) could effectively

• promote this cascade reaction for the synthesis of quinazolinones without the need for additional ligands or additives (Scheme 1a) [7][10]. Since then, various copper-based catalysts, both homogeneous and heterogeneous, have been explored (Scheme 1b) [11][12][13][14][15][16]. For example, Wang’s group

• efficient, reusable heterogeneous catalyst for this cascade reaction, achieving good to excellent yields without any loss of activity even after ten cycles of simple filtration-based recovery [12]. Moreover, a copper catalyst has been shown to function effectively in both organic and aqueous media [13][14

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

• –Alder reaction between an imine and an alkene (Scheme 6). Very successfully, the multicomponent version of the Povarov reaction using aldehydes, anilines, and alkenes has been explored in a three-component cascade reaction to quinolines [28][29][30][31] (Scheme 6). Furthermore, protocols have been

• various substitution patterns in the aromatic ring, allowing a high variety of quinolines of general structure I and II. In a related work, quinolines of structure I (Scheme 8) could be obtained by similar reaction pathways. Jadhav et al. proposed a three-component cascade reaction between anilines

• all of these authors confirmed, after analyzing the position of the deuterium atoms in the final compound, that the methylene unit incorporated into the heterocycle came from DMSO. In the case of pyrazole synthesis, Guo et al. proposed a three-component cascade reaction of enaminones, hydrazines, and

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

• organocatalytic synthesis of 2-cyclohexen-1-ones via a Michael/Michael/retro-Michael cascade reaction [31]. Our research has shown that the Jørgensen–Hayashi catalyst [32][33] is a highly promising organocatalyst, facilitating enantioselective Michael addition reactions with high yields and excellent levels of

Streamlined modular synthesis of saframycin substructure via copper-catalyzed three-component assembly and gold-promoted 6-endo cyclization

• Asahi Kanno,
• Ryo Tanifuji,
• Satoshi Yoshida,
• Sota Sato,
• Saori Maki-Yonekura,
• Kiyofumi Takaba,
• Jungmin Kang,
• Kensuke Tono,
• Koji Yonekura and
• Hiroki Oguri

Beilstein J. Org. Chem. 2025, 21, 226–233, doi:10.3762/bjoc.21.14

• -fluorobenzene (see Scheme 2 and Supporting Information File 1 for details). Copper(I)-catalyzed three-component coupling reaction of alkyne 8, THIQ 9, and benzaldehyde, proceeded with exquisite control of regioselectivity to afford 10 in an excellent yield of 92% [43][44][45][46]. This efficient cascade

• reaction involves an in situ generation of the iminium cation A followed by isomerization to the thermodynamically more stable iminium cation B. Subsequent nucleophilic attack of a copper acetylide enabled regioselective C–C bond formation at the C11 position. After removal of the cyclic acetal, the

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

• directly to the alkene, then reacts with the nucleophile to afford product 7. The regioselective 1,2-difunctionalization of allyl alcohol has been developed as a three-component cascade reaction using arenes and sulfonamides as nucleophiles to achieve arylation/hydroamination processes. The reaction

• cascade reaction for the preparation of α-alkoxy-N-alkyltriazoles 44 that was developed starting from aliphatic aldehydes, alcohols, TMSN3 as azide source and alkynes (Scheme 33) [52]. The reaction occurs under mild conditions in acetonitrile at room temperature but is inhibited when using aromatic

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

• the final step of the reaction, ring opening by the C–C bond cleavage yields the desired product 203. The first phosphoric acid C39-catalyzed asymmetric cycloaddition–elimination cascade reaction of 2-naphthol or phenol enamide derivatives 204 with azonaphthalenes 205 was done by Xu et al. in 2021

Synthesis of acenaphthylene-fused heteroarenes and polyoxygenated benzo[j]fluoranthenes via a Pd-catalyzed Suzuki–Miyaura/C–H arylation cascade

• Merve Yence,
• Dilgam Ahmadli,
• Damla Surmeli,
• Umut Mert Karacaoğlu,
• Sujit Pal and
• Yunus Emre Türkmen

Beilstein J. Org. Chem. 2024, 20, 3290–3298, doi:10.3762/bjoc.20.273

• )-catalyzed [2 + 2 + 2] cycloaddition reactions with 1,8-dialkynylnaphthalenes to access azafluoranthenes and 2-pyridone-fused naphthalenes [27]. In 2017, we reported a Pd-catalyzed cascade reaction that involves a sequential Suzuki–Miyaura cross-coupling and a subsequent intramolecular C–H arylation between

• methodology, the previously known naphthalene dibromide 14 was prepared in two steps from 1,8-DHN (19) [56] serving as the second coupling partner. The Pd-catalyzed cascade reaction between 14 and 22 afforded the targeted benzo[j]fluoranthene 18 in 52% yield. Overall, the synthesis of 18, which was used as

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

• -isothiocyanatooxindole. Cinchona-derived thiourea-catalyzed stereoselective (3 + 2)/(4 + 2) cascade reaction of α,β-unsaturated imines and 3-isothiocyanatooxindole. Enantioselective bifunctional squaramide-catalyzed formal [4 + 2] cycloaddition of malononitrile with benzofuran-derived azadienes. Bifunctional squaramide

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

• (R = EWG-C6H4, E = PhS and PhTe) in moderate to high yields [30]. Very few examples of intermolecular cascade reactions with imidoyl radicals as key intermediates have been reported. The intermolecular cascade reaction of diselenide, electron-deficient acetylene, and isocyanide under photoirradiation

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

• study, many research groups described a strategy for ortho-C–H functionalization of aryl sulfoxides with various nucleophiles via a cascade reaction of interrupted Pummerer reaction/sigmatropic rearrangement (Scheme 1a) [6][7][8][9][10][11]. A large range of nucleophiles, such as phenols [12][13][14][15

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

• substrates in the cascade reaction of curcumins employing a biphasic solvent system for the synthesis of highly functionalized cyclohexanones and tetrahydrochromenes. In view of the above, we report herein cascade double and triple Michael reactions of curcumins with arylidenemalonates in the presence of a