Synthesis of diaryl phosphates using phytic acid as a phosphorus source

• Kazuya Asao,
• Seika Matsumoto,
• Haruka Mori,
• Riku Yoshimura,
• Takeshi Sasaki,
• Naoya Hirata,
• Yasuyuki Hayakawa and
• Shin-ichi Kawaguchi

Beilstein J. Org. Chem. 2026, 22, 213–223, doi:10.3762/bjoc.22.15

• phosphoric acid and condensed phosphoric acid into a versatile PO2+ phosphorylation agent, (pyridine)2PO2[OTf]. The intermediate reacts with a variety of nucleophiles, providing a redox-neutral method for the flexible synthesis of P(V) compounds (Figure 2C) [44]. Furthermore, Naganawa’s group recently

Circumventing Mukaiyama oxidation: selective S–O bond formation via sulfenamide–alcohol coupling

• Guoling Huang,
• Huarui Zhu,
• Shuting Zhou,
• Wanlin Zheng,
• Fangpeng Liang,
• Zhibo Zhao,
• Yifei Chen and
• Xunbo Lu

Beilstein J. Org. Chem. 2026, 22, 158–166, doi:10.3762/bjoc.22.9

• , such transformations remain synthetically challenging. This is primarily due to the well-known Mukaiyama-type oxidation, wherein sulfenamides serve as redox catalysts for NBS- or NCS-mediated oxidations of alcohols to aldehydes or ketones (Scheme 1b, top) [38][39][40][41][42]. Under such oxidative

Total synthesis of natural products based on hydrogenation of aromatic rings

• Haoxiang Wu and
• Xiangbing Qi

Beilstein J. Org. Chem. 2026, 22, 88–122, doi:10.3762/bjoc.22.4

Advances in Zr-mediated radical transformations and applications to total synthesis

• Hiroshige Ogawa and
• Hugh Nakamura

Beilstein J. Org. Chem. 2026, 22, 71–87, doi:10.3762/bjoc.22.3

• Yamaguchi published a review on radical reactions catalyzed by zirconium complexes [6]. Their review provides a comprehensive summary, particularly of photo-redox reactions involving zirconium catalysis. In the present review, we focus on three aspects: 1) Zr-mediated stoichiometric radical reactions 2) Zr

Sustainable electrochemical synthesis of aliphatic nitro-NNO-azoxy compounds employing ammonium dinitramide and their in vitro evaluation as potential nitric oxide donors and fungicides

• Alexander S. Budnikov,
• Nikita E. Leonov,
• Michael S. Klenov,
• Andrey A. Kulikov,
• Igor B. Krylov,
• Timofey A. Kudryashev,
• Aleksandr M. Churakov,
• Alexander O. Terent’ev and
• Vladimir A. Tartakovsky

Beilstein J. Org. Chem. 2025, 21, 2739–2754, doi:10.3762/bjoc.21.211

• , structures, and redox properties, effective synthetic strategies for the construction of N–N and N–O systems remain markedly underdeveloped. Unlike traditional methods for constructing C–C and C–Het bonds, the number of methods for selective N–N [1][5][19][20][21][22][23][24][25][26][27][28][29] and N–O [30

Recent advancements in the synthesis of Veratrum alkaloids

• Morwenna Mögel,
• David Berger and
• Philipp Heretsch

Beilstein J. Org. Chem. 2025, 21, 2657–2693, doi:10.3762/bjoc.21.206

• well as showcasing step- and redox-economy. This representation will be highly valuable for comparing the presented synthetic routes at the end of each subclass. Review Synthesis of Veratrum alkaloids The biological activities of the Veratrum alkaloids have been widely studied, but their synthesis

• moiety was introduced as a precursor to an aldehyde, which was obtained by reduction of 46 to 47. For the right-hand fragment (ring D, E, and F), an asymmetric hydrogenation of α-substituted acrylic acid 48 was performed, followed by redox manipulations to give aldehyde 49 over 3 steps in 95% and an

• oxidation and the double bond installation mentioned, including several redox manipulations and protecting group removals. In total, the Masamune group reported the total synthesis of jervine (12) from Hagemann’s ester (61) in 47 steps in the LLS and a total of 49 steps. Not all yields were reported, so no

Visible-light-driven NHC and organophotoredox dual catalysis for the synthesis of carbonyl compounds

• Vasudevan Dhayalan

Beilstein J. Org. Chem. 2025, 21, 2584–2603, doi:10.3762/bjoc.21.200

• , tolerates a variety of functional groups, and offers a wide substrate scope. Under the optimized conditions, Rb2CO3 provided better results than DMAP and Cs2CO3. The acyl azolium complex B was synthesized from acyl imidazole 9 using an NHC and Rb2CO3 as the base. Considering the redox potential of 4CzIPN

• organophotocatalyst (3DPAFIPN) was employed, significant amounts of cyclized product were observed and suggesting that the necessary redox potentials fall near its redox range (E1/2 PC*/PC•− to E1/2 PC/PC•− = +1.09 to −1.59 V vs SCE). This catalytic method provides an efficient route for synthesizing complex

Total syntheses of highly oxidative Ryania diterpenoids facilitated by innovations in synthetic strategies

• Zhi-Qi Cao,
• Jin-Bao Qiao and
• Yu-Ming Zhao

Beilstein J. Org. Chem. 2025, 21, 2553–2570, doi:10.3762/bjoc.21.198

• successfully accomplished via an epoxide ring-opening/tandem lactonization/olefin hydration sequence. In total, 12 consecutive redox manipulations (7 oxidations and 5 reductions) established all stereocenters, with subsequent functional group transformations completing the total synthesis of garajonone (8

Synthesis and characterization of a isothiouronium-calix[4]arene derivative: self-assembly and anticancer activity

• Giuseppe Granata,
• Loredana Ferreri,
• Claudia Giovanna Leotta,
• Giovanni Mario Pitari and
• Grazia Maria Letizia Consoli

Beilstein J. Org. Chem. 2025, 21, 2535–2541, doi:10.3762/bjoc.21.195

• mechanisms including elevation of reactive oxygen species (ROS) or interference with redox homeostasis, and inhibition of kinase or topoisomerase activities essential for cancer cell proliferation. The selective activity of thiouronium salts against cancer cells compared to non-malignant cells can be related

Synthesis of the tetracyclic skeleton of Aspidosperma alkaloids via PET-initiated cationic radical-derived interrupted [2 + 2]/retro-Mannich reaction

• Ru-Dong Liu,
• Jian-Yu Long,
• Zhi-Lin Song,
• Zhen Yang and
• Zhong-Chao Zhang

Beilstein J. Org. Chem. 2025, 21, 2470–2478, doi:10.3762/bjoc.21.189

• -initiated [2 + 2] cyclization of the tryptamine-substituted cyclobutenone K to form the radical cation L, which has a highly functionalized and rigid bicyclo[2.2.0]hexane core. Fragmentation of the C3–C19 bond would afford a redox-active intermediate which upon further reductive quenching would lead to the

Rotaxanes with integrated photoswitches: design principles, functional behavior, and emerging applications

• Jullyane Emi Matsushima,
• Khushbu,
• Zuliah Abdulsalam,
• Udyogi Navodya Kulathilaka Conthagamage and
• Víctor García-López

Beilstein J. Org. Chem. 2025, 21, 2345–2366, doi:10.3762/bjoc.21.179

• bulky stoppers at both ends to prevent dethreading (Figure 1) [1][8]. Functionalization of the axle with recognition sites allows the macrocycle to shuttle between positions in response to external stimuli, including light, redox, temperature, pH, and reactions with chemicals such as carbodiimides [9

Recent advances in Norrish–Yang cyclization and dicarbonyl photoredox reactions for natural product synthesis

• Peng-Xi Luo,
• Jin-Xuan Yang,
• Shao-Min Fu and
• Bo Liu

Beilstein J. Org. Chem. 2025, 21, 2315–2333, doi:10.3762/bjoc.21.177

• converting the biradical to the corresponding zwitterion; (3) oxy-cyclization to afford the product. This process constitutes an intramolecular redox reaction, wherein the quinone is reduced to a hydroquinone while the proximal C–H bond is oxidized to a C–O bond. Although related photoredox reactions had

Enantioselective radical chemistry: a bright future ahead

• Anna C. Renner,
• Sagar S. Thorat,
• Hariharaputhiran Subramanian and
• Mukund P. Sibi

Beilstein J. Org. Chem. 2025, 21, 2283–2296, doi:10.3762/bjoc.21.174

• abundance, low cost, less toxicity, and existence of multiple oxidation states (I, II, and III) make copper an essential transition metal for catalytic purposes [60][61]. The fact that copper, like other transition metals, has multiple oxidation states makes it an excellent redox catalyst. Owing to the

• was the use of ferrocene as a redox mediator, which played an important role in preventing substrate decomposition under the electrochemical conditions. An electrochemical method enabled regio- and enantioselective radical reactions of silyl polyenolates with racemic α-branched esters, yielding

Pathway economy in cyclization of 1,n-enynes

• Hezhen Han,
• Wenjie Mao,
• Bin Lin,
• Maosheng Cheng,
• Lu Yang and
• Yongxiang Liu

Beilstein J. Org. Chem. 2025, 21, 2260–2282, doi:10.3762/bjoc.21.173

• enabling more efficient utilization of limited raw materials [1][2]. Two years later, Wender proposed “step economy” advocating optimized synthetic routes and strategies to minimize the number of steps required for constructing target molecules [3][4]. In 2008, “redox economy” was introduced by Baran [5

• ]. Similar to “atom and step economies”, this concept emphasizes prioritizing the minimization of redox manipulations during synthesis to achieve linear and stable progression of oxidation states in intermediates. In recent years, “pot economy” and “time economy” were proposed by Hayashi, underscoring the

• circumvents cumbersome late-stage functional group manipulations and perfectly aligns with the principles of step economy, time economy, and redox economy. Over the past few decades, chemists have rapidly directed this efficient synthetic paradigm toward diverse targets by skillfully regulating reaction

Electrochemical cyclization of alkynes to construct five-membered nitrogen-heterocyclic rings

• Lifen Peng,
• Ting Wang,
• Zhiwen Yuan,
• Bin Li,
• Zilong Tang,
• Xirong Liu,
• Hui Li,
• Guofang Jiang,
• Chunling Zeng,
• Henry N. C. Wong and
• Xiao-Shui Peng

Beilstein J. Org. Chem. 2025, 21, 2173–2201, doi:10.3762/bjoc.21.166

• transformations far from thermodynamic equilibria have emerged abundantly with the consideration of green chemistry [89][90][91][92]. Redox-active organic compounds, transition metal coordinating compounds and even an electrode surface were commonly employed as catalysts in the electrochemical transformations [93

• ]. Besides, electrochemical cyclization of alkynes is also an important access towards indoles. In 2016, Xu reported the electrochemical intramolecular coupling of urea derivatives to form substituted indoles (Scheme 1) [162]. Using [Cp2Fe] (5 mol %) as the redox catalyst, the intramolecular coupling of

• cationic resonance G quickly. The nucleophilic attack of D2O formed H, which underwent dedeuteration and elimination of DI to form 30a with reduction of deuterated water to generate deuteroxyl ions (OD−) and deuterium gas (D2) at the cathode. This method, using iodide salts as electrolyte and redox

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

• Meerwein–Ponndorf–Verley reduction, while acetaldehyde is generated in situ by ethanol oxidation (Scheme 50). The equilibrium allows furfural to be simultaneously converted into furfuryl alcohol and 3-(2-furyl)acrolein in one pot through a redox reaction. The highest mass conversion rate of furfural can

Multicomponent reactions IV

• Thomas J. J. Müller and
• Valentyn A. Chebanov

Beilstein J. Org. Chem. 2025, 21, 2082–2084, doi:10.3762/bjoc.21.163

• a strong emphasis on heterocycle synthesis. Beyond traditional condensation-based approaches, mechanistically innovative crossovers – linking metal catalysis with radical chemistry and, more recently, with photo(redox) catalysis – are opening entirely new avenues for MCR development. Finally, seven

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

• approach. This key reaction mimics the plausible biosynthetic pathway and demonstrates great efficiency and sole diastereoselectivity, showcasing the plausibility of the biosynthetic proposal. Further redox manipulations of the last olefin and deprotection ultimately provided chabranol. To clearly confirm

• oxa-carbenium cation triggered by an acid to proceed a Friedel–Crafts reaction to afford the dibenzocyclooctene skeleton. On the other hand, eupomatilone would undergo redox transformations to generate another oxa-carbenium cation to undergo a Friedel–Crafts reaction to form a spirocyclic skeleton

Photochemical reduction of acylimidazolium salts

• Michael Jakob,
• Nick Bechler,
• Hassan Abdelwahab,
• Fabian Weber,
• Janos Wasternack,
• Leonardo Kleebauer,
• Jan P. Götze and
• Matthew N. Hopkinson

Beilstein J. Org. Chem. 2025, 21, 1973–1983, doi:10.3762/bjoc.21.153

• acid derivative substrates [16]. Over the last few years, a wide range of valuable NHC-catalyzed transformations have also been developed that incorporate redox steps. As an enamine species, single-electron oxidation of a Breslow intermediate is comparatively favored with the resulting open shell

• direct excitation of the benzoylazolium salt with the excited state species 1*, which subsequently reacts with TESH. Comparison of the redox potential of the silane (+1.54 V vs ferrocene) with the estimated excited-state potential of the azolium salt 1* (+1.70 V vs ferrocene) suggest that direct electron

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

• diastereoselectivity. Compound 288 was then treated with Co(acac)2, 1,1,3,3-tetramethyldisiloxane (TMDSO), and O2 in degassed iPrOH, undergoing a hydrogen-atom-transfer (HAT)-initiated redox radical cascade to give pentacyclic alcohol 289, which was converted to C18/19 diol 290 in two steps. To differentiate the two

Synthesis of N-doped chiral macrocycles by regioselective palladium-catalyzed arylation

• Shuhai Qiu and
• Junzhi Liu

Beilstein J. Org. Chem. 2025, 21, 1917–1923, doi:10.3762/bjoc.21.149

• -bridged structural analogs of [1n]metacyclophanes. In comparison to all-carbon [1n]metacyclophanes, the incorporation of N atoms endows them with unique features, such as enhanced molecular dynamics and tunable redox property, positioning them as key precursors to construct organic high-spin materials [20

Synthesis, biological and electrochemical evaluation of glycidyl esters of phosphorus acids as potential anticancer drugs

• Almaz A. Zagidullin,
• Emil R. Bulatov,
• Mikhail N. Khrizanforov,
• Damir R. Davletshin,
• Elvina M. Gilyazova,
• Ivan A. Strelkov and
• Vasily A. Miluykov

Beilstein J. Org. Chem. 2025, 21, 1909–1916, doi:10.3762/bjoc.21.148

• alkylating agents 1–3. The motivation behind these experiments was to explore whether these compounds, which individually exhibit no appreciable redox activity in the potential window applied, can chemically modify (alkylate) serum albumin and thus suppress its characteristic oxidation peaks. Human serum

• themselves exhibit no discernible redox activity in this potential range when tested in the absence of HSA. Consequently, any changes in the recorded voltammogram could be attributed to the interaction (alkylation) of albumin rather than to new electrochemical processes arising directly from the compounds

Stereoselective electrochemical intramolecular imino-pinacol reaction: a straightforward entry to enantiopure piperazines

• Margherita Gazzotti,
• Fabrizio Medici,
• Valerio Chiroli,
• Laura Raimondi,
• Sergio Rossi and
• Maurizio Benaglia

Beilstein J. Org. Chem. 2025, 21, 1897–1908, doi:10.3762/bjoc.21.147

• voltammetry measurements were also carried out in order to evaluate the electrochemical redox properties of the species involved in the process and to provide evidence for the behavior of the monoprotonated and the bisprotonated diimines, 3a and 4a (Scheme 8). The cyclic voltammogram of the starting diimine

Research progress on calixarene/pillararene-based controlled drug release systems

• Liu-Huan Yi,
• Jian Qin,
• Si-Ran Lu,
• Liu-Pan Yang,
• Li-Li Wang and
• Huan Yao

Beilstein J. Org. Chem. 2025, 21, 1757–1785, doi:10.3762/bjoc.21.139

• times. This bis-vesicle structure possesses the following intelligent responsive characteristics: (1) temperature sensitivity originating from the enthalpy-driven nature of the host–guest interaction; (2) redox responsiveness due to the reversible electron transfer of MVC12; (3) competitive complexation

• making the system sensitive to cyclodextrins. Experiments have confirmed that this carrier can efficiently encapsulate DOX and trigger drug release through multiple stimuli, demonstrating good potential for anticancer therapy in vitro. This intelligent delivery system, integrating temperature, redox, and

Photocatalysis and photochemistry in organic synthesis

• Timothy Noël and
• Bartholomäus Pieber

Beilstein J. Org. Chem. 2025, 21, 1645–1647, doi:10.3762/bjoc.21.128

• ) transition, resulting in a long-lived charge-separated species. In this excited state, [Ru(bpy)3]Cl2 is both a more potent oxidant and reductant than in its ground state. This reactivity, in combination with the reversible redox behavior of the metal complex, enables reductive or oxidative quenching cycles