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

• % with HAuBr4 (i.e., practically identical to that of KAuBr4). The process of recovery was tested at the laboratorial scale on a spent gold-bearing alloy cable obtained from a local electronic junk shop. The cable was leached with HBr/H2O2 to obtain a solution of HAuBr4, which was treated with a

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

• situ formation of an active enol ester 26. The phenol was formed in situ during the second step from phenylboronic acid oxidation utilizing H2O2 (30%) as green oxidant (Scheme 8B) [40]. Sureshbabu and co-workers (2023) activated the carboxyl group of 4-hydroxycinnamic acid (1) by selectively reacting

• (2021) developed a Cr-based catalyst stabilized by a pentaerythritol-decorated Anderson-type polyoxometalate, [N(C4H9)4]3[CrMo6O18(OH)3C{(OCH2)3CH2-OH}] (cat 3), to catalyze the oxidative esterification of cinnamyl alcohols using H2O2. The reaction proceeds also via a hemiacetal intermediate 155 (Scheme

• -workers (2023) employed a Cu(II) square-planar complex {[CuIIL] LH2, 9,9’-(ethane-1,2-diylbis(azanediyl))bis(1H-phenalen-1-one} to convert cinnamaldehyde (162) into methyl cinnamate (44) in the presence of H2O2 as green oxidant via intermediate 164 formation (Scheme 52B) [93]. Using a different earth

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

• and n-BuLi, followed by a reaction with ZnCl2 at room temperature. The product is then hydrolyzed with a NaOH solution of H2O2 to yield amino alcohols. The mechanism involves the formation of borate intermediate Int-79 from substrate 83 under the action of CH2BrLi. This is followed by an N-1,2

Light-enabled intramolecular [2 + 2] cycloaddition via photoactivation of simple alkenylboronic esters

• Lewis McGhie,
• Hannah M. Kortman,
• Jenna Rumpf,
• Peter H. Seeberger and
• John J. Molloy

Beilstein J. Org. Chem. 2025, 21, 854–863, doi:10.3762/bjoc.21.69

• cyclobutyldiol. A) Product derivatization and B) transition-metal EnT catalysis. Reaction conditions A): 4d (1 equiv), H2O2 (30 wt % in H2O), aq NaH2PO4, THF, 0 °C; B) 4 (1 equiv), KF (4 equiv), ʟ-tartaric acid (2.1 equiv), MeOH, MeCN, H2O, rt. Probing EnT catalysis of alkenylboronic ester 1a via alkene

Synthesis, characterization, and photophysical properties of novel 9‑phenyl-9-phosphafluorene oxide derivatives

• Shuxian Qiu,
• Duan Dong,
• Jiahui Li,
• Huiting Wen,
• Jinpeng Li,
• Yu Yang,
• Shengxian Zhai and
• Xingyuan Gao

Beilstein J. Org. Chem. 2024, 20, 3299–3305, doi:10.3762/bjoc.20.274

• % yield over 2 steps) [34]. Upon exposure to NaNO2/HCl, diamine 3 was transformed into a diazonium salt, which was captured by KI to deliver the diiodide 4. Treatment of 4 with n-BuLi, PhPCl2, and H2O2 sequentially gave 2,8-difluoro-5-phenylbenzo[b]phosphindole 5-oxide (5) in 68% yield. With compound 5 in

Multicomponent reactions driving the discovery and optimization of agents targeting central nervous system pathologies

• Lucía Campos-Prieto,
• Aitor García-Rey,
• Eddy Sotelo and
• Ana Mallo-Abreu

Beilstein J. Org. Chem. 2024, 20, 3151–3173, doi:10.3762/bjoc.20.261

• effects against toxic insults such as H2O2 and Aβ-peptides (Scheme 6). Additionally, compound 6a showed promising activity in activating the Nrf2 signaling pathway, indicating its potential to mitigate OS and inflammation in AD. These findings highlight FATMH 6a as a promising lead compound for further

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

• to the vacant axial site of the metal centers. This binding is followed by reduction to either hydrogen peroxide (H2O2) via a two-electron (2e−) pathway, water (H2O) through a four-electron (4e−) pathway, or a combination of both products through a concerted transfer of electrons and protons [126

• reduction of O2 to H2O2 and/or to H2O, Samec and co-workers have done a substantial amount of work exploring the use of metal-free porphyrins as catalysts for ORR [113][114][115][116][117][118]. They reported that metal-free porphyrin macrocycles; 109 (5-(p-aminophenyl)-10,15,20-tris(pentafluorophenyl

• )porphyrin, H2FAP), and 18 (5,10,15,20-meso-tetraphenylporphyrin, H2TPP) can catalyze oxygen reduction to H2O2 using ferrocene-based electron donors [ferrocene (Fc) and decamethylferrocene (DMFc)] at acidified water/1,2-dichloroethane (DCE) interface [115][117]. This two-phasic oxygen reduction undergoes via

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

• mainly include: nucleophilic addition or nucleophilic substitution with H2O2 or ROOH [17][18], autoxidation with O2, pericyclic reactions of unsaturated bonds with O3 or O2, and metal-catalyzed peroxidation (Isayama–Mukaiyama hydrosilylperoxidation [19][20], for example) [21][22][23]. As the topic is

Efficient modification of peroxydisulfate oxidation reactions of nitrogen-containing heterocycles 6-methyluracil and pyridine

• Alfiya R. Gimadieva,
• Yuliya Z. Khazimullina,
• Aigiza A. Gilimkhanova and
• Akhat G. Mustafin

Beilstein J. Org. Chem. 2024, 20, 2599–2607, doi:10.3762/bjoc.20.219

• in two different ways: with metallophthalocyanine catalysts present and by including hydrogen peroxide as a co-oxidant (Scheme 1). Metal–phthalocyanine complexes (PcM) are recognized as catalysts for gentle, particular oxidation reactions under aerobic [14] and H2O2-based conditions [15][16][17][18

• − ion, which is formed by the non-radical decomposition of the peroxydisulfate ion in a strongly alkaline medium [34]: The Elbs and Boyland–Sims reactions were also effectively modified by the use of H2O2 as a co-oxidant (binary oxidation mixture APS/H2O2). Adding 2.0–2.3 equiv of H2O2 (Table 3) [35

• pyrimidine ring destruction. The ideal oxidation of TMU (5) was achieved with the addition of 3.0–4.0 equiv H2O2 (Table 3). During the oxidation of pyridine (7) by the binary oxidation mixture APS/H2O2 at 45 °C, the yield of the reaction product – Py-sulfate 8 – increased gradually, reaching a maximum of 85

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

• of the oxidative conditions used (mCPBA [75], H2O2 [75], selectfluor®/H2O [76], SO2Cl2/NaHCO3 (aq) [77][78]), in most cases a complex mixture was observed and no corresponding vinylic compound was detected by NMR. The phenylselenyl moiety could also undergo radical reduction to produce

Understanding X-ray-induced isomerisation in photoswitchable surfactant assemblies

• Beatrice E. Jones,
• Camille Blayo,
• Jake L. Greenfield,
• Matthew J. Fuchter,
• Nathan Cowieson and
• Rachel C. Evans

Beilstein J. Org. Chem. 2024, 20, 2005–2015, doi:10.3762/bjoc.20.176

• process that generates a wide variety of primary species, including e−, HO•, H•, HO2•, H+, OH−, H2O2 and H2 [36]. For Azo photoswitches, the formation of H+ species, i.e., the acidification effect, can catalyse the Z–E isomerisation reaction. This is due to protonation of one of the nitrogen atoms in the

Syntheses and medicinal chemistry of spiro heterocyclic steroids

• Laura L. Romero-Hernández,
• Ana Isabel Ahuja-Casarín,
• Penélope Merino-Montiel,
• Sara Montiel-Smith,
• José Luis Vega-Báez and
• Jesús Sandoval-Ramírez

Beilstein J. Org. Chem. 2024, 20, 1713–1745, doi:10.3762/bjoc.20.152

New triazinephosphonate dopants for Nafion proton exchange membranes (PEM)

• Fátima C. Teixeira,
• António P. S. Teixeira and
• C. M. Rangel

Beilstein J. Org. Chem. 2024, 20, 1623–1634, doi:10.3762/bjoc.20.145

• annellation for 2 h, at 140 °C. The membranes were activated by a sequential treatment, with 1 h for each step, by boiling them in H2O2 solution (3%), washing with hot deionized water, boiling in a 0.5 M sulfonic acid solution, and washing again with hot deionized water. After activation, the membranes were

Tetrabutylammonium iodide-catalyzed oxidative α-azidation of β-ketocarbonyl compounds using sodium azide

• Christopher Mairhofer,
• David Naderer and
• Mario Waser

Beilstein J. Org. Chem. 2024, 20, 1510–1517, doi:10.3762/bjoc.20.135

• ammonium iodides [40]. Interestingly, designer catalyst C1 was found being catalytically superior compared to Bu4NI (TBAI) when using H2O2 as the oxidant. Furthermore, it turned out that addition of PBN (phenyl N-tert-butylnitrone) has a beneficial effect on the reaction and that carefully buffered

• -heterofunctionalizations before [39], showed that DBPO clearly outperforms all the other oxidants tested under these conditions (Table 1, entries 1–5). While H2O2 gave 2a in low yield only (Table 1, entry 1), the use of mCPBA (Table 1, entry 3) and t-BuOOH (Table 1, entry 4) mainly resulted in the formation of the α-OH

Synthesis of 4-functionalized pyrazoles via oxidative thio- or selenocyanation mediated by PhICl₂ and NH₄SCN/KSeCN

• Jialiang Wu,
• Haofeng Shi,
• Xuemin Li,
• Jiaxin He,
• Chen Zhang,
• Fengxia Sun and
• Yunfei Du

Beilstein J. Org. Chem. 2024, 20, 1453–1461, doi:10.3762/bjoc.20.128

• , Yotphan and colleagues realized a direct thiocyanation of N-substituted pyrazolones under metal-free conditions [49]. Besides, Choudhury and co-workers developed an additive and metal-free methodology for the C–H thiocyanation of aminopyrazoles, using H2O2 as a benign oxidizing agent (Scheme 1b) [41]. Pan

Competing electrophilic substitution and oxidative polymerization of arylamines with selenium dioxide

• Vishnu Selladurai and
• Selvakumar Karuthapandi

Beilstein J. Org. Chem. 2024, 20, 1221–1235, doi:10.3762/bjoc.20.105

• rise to either diaryl selenoxide via dehydration or diaryl monoselenide via reductive elimination by eliminating H2O2 [39]. Observation of m/z peaks for compound 8 clearly confirmed the formation of diaryl selenoxide in the reaction. Mechanism for the formation of oxamides The possible reaction

Light on the sustainable preparation of aryl-cored dibromides

• Fabrizio Roncaglia,
• Alberto Ughetti,
• Nicola Porcelli,
• Biagio Anderlini,
• Andrea Severini and
• Luca Rigamonti

Beilstein J. Org. Chem. 2024, 20, 1076–1087, doi:10.3762/bjoc.20.95

• ion in aqueous acidic media (Equation 1) [43]. Its practical implementation is surprisingly simple as standard aqueous HBr and H2O2 solutions are effective. The generated bromine can be involved in different chemical mechanisms, such as an Ar-SE (Equation 2) [44] or a radical substitution on activated

• as the activator, and hydrogen peroxide was slowly added, by means of a syringe pump. As the bromine colour generated after each H2O2 drop disappeared quickly, the reaction time was reduced from 24 h to 8 h. In these conditions, the process exhibited complete conversion, but strong selectivity in

• negligible adsorption of Br2 at wavelengths shorter than 380 nm [52]. We finally evaluated a variation in the H2O2/HBr molar ratio to determine the optimal amount of H2O2, typically used in a twofold molar ratio relative to HBr [49]. These experiments raised on the observation of gas evolution (presumably O2

Confirmation of the stereochemistry of spiroviolene

• Yao Kong,
• Yuanning Liu,
• Kaibiao Wang,
• Tao Wang,
• Chen Wang,
• Ben Ai,
• Hongli Jia,
• Guohui Pan,
• Min Yin and
• Zhengren Xu

Beilstein J. Org. Chem. 2024, 20, 852–858, doi:10.3762/bjoc.20.77

• BH3·THF in THF, and heated at 60 °C for 3 days. After oxidative treatment of the resultant alkylborane products with NaOH/H2O2, we have obtained three derivatives 9–11 with one hydroxy group in 37%, 30% and 21% isolated yield, respectively, as well as recovery of 10% of the starting material. After

• intermediate IM-13, or a tertiary 2-organoborane intermediate IM-14. Oxidation of IM-13 with H2O2/NaOH could stereoselectively furnish the normal hydroboration/oxidation product 9. On the other hand, the unstable tertiary 2-organoborane IM-14 would undergo two consecutive thermal 1,2-boron migrations to give

• the 9-organoborane intermediate IM-16 probably through borane–olefin complexes. The suprafacial nature of the boron migration allowed the boron to be α-oriented in intermediate IM-16, which would give 10 with retention of the configuration after NaOH/H2O2 oxidation. The formation of a significant

Methodology for awakening the potential secondary metabolic capacity in actinomycetes

• Shun Saito and
• Midori A. Arai

Beilstein J. Org. Chem. 2024, 20, 753–766, doi:10.3762/bjoc.20.69

• ), which upon sensing ROS, release their repression and activate the expression of various genes [93][94][95]. Wei et al. reported that the production of validamycin A (25) by Streptomyces hygroscopicus 5008 could be activated at the transcriptional level by simply adding hydrogen peroxide (H2O2; which

• in the genetically programmed death of the producing organism. In addition, Nishiyama et al. suggested that actinorhodin (8) produced by Streptomyces coelicolor A3(2) functions as an organocatalyst to kill bacteria by catalyzing the production of toxic levels of H2O2 [99]. They also suggested that

Regioselective quinazoline C2 modifications through the azide–tetrazole tautomeric equilibrium

• Dāgs Dāvis Līpiņš,
• Andris Jeminejs,
• Una Ušacka,
• Anatoly Mishnev,
• Māris Turks and
• Irina Novosjolova

Beilstein J. Org. Chem. 2024, 20, 675–683, doi:10.3762/bjoc.20.61

• were oxidized to the corresponding sulfonylquinazolines 8. Inspired by our previous work [19] a TFAA/H2O2 oxidizing system was tried first but yielded several side-products, such as the hydrolysis product and unwanted oxidation of the quinazoline N3 position. Changing the oxidant to mCPBA (with 96

Chemical and biosynthetic potential of Penicillium shentong XL-F41

• Ran Zou,
• Xin Li,
• Xiaochen Chen,
• Yue-Wei Guo and
• Baofu Xu

Beilstein J. Org. Chem. 2024, 20, 597–606, doi:10.3762/bjoc.20.52

• ; FeSO4 1 µM; KI 2 g/L, KCl 2 g/L, KBr 2 g/L, NaNO2 2 g/L; H2O2 20 µM; (methyl jasmonate) MeJA 10 µM). XISR III medium (yeast extract 4 g/L; soy flour 10 g/L; glucose 30 g/L; MgCl2 1 µM; FeSO4 1 µM; KI 2 g/L, KCl 2 g/L, KBr 2 g/L, NaNO2 2 g/L; H2O2 20 µM; MeJA 10 µM; 5-azacytidine 6 µM; suberoylanilide

Unveiling the regioselectivity of rhodium(I)-catalyzed [2 + 2 + 2] cycloaddition reactions for open-cage C₇₀ production

• Cristina Castanyer,
• Anna Pla-Quintana,
• Anna Roglans,
• Albert Artigas and
• Miquel Solà

Beilstein J. Org. Chem. 2024, 20, 272–279, doi:10.3762/bjoc.20.28

• the hole is closed restoring the original cage. Among the species that have been incarcerated with this procedure, we can find He, Ne, Ar, Kr, H2, N2, O2, HF, CO, CO2, H2O, H2O2, CH4, NH3, HCOH, HCCH, and CH3OH [26][27]. The encapsulation of atoms or small molecules inside the fullerene has been found

Aromatic systems with two and three pyridine-2,6-dicarbazolyl-3,5-dicarbonitrile fragments as electron-transporting organic semiconductors exhibiting long-lived emissions

• Karolis Leitonas,
• Brigita Vigante,
• Dmytro Volyniuk,
• Audrius Bucinskas,
• Pavels Dimitrijevs,
• Sindija Lapcinska,
• Pavel Arsenyan and
• Juozas Vidas Grazulevicius

Beilstein J. Org. Chem. 2023, 19, 1867–1880, doi:10.3762/bjoc.19.139

• the photocatalytic production of H2 while the nanospheres produced hydrogen peroxide (H2O2). The introduction of the additional carbazolylphenyl moiety in the CPC molecule [4] allowed us to improve the EQEmax of an OLED to 25% [7]. In continuation of our studies in the field of the development of new

Radical chemistry in polymer science: an overview and recent advances

• Zixiao Wang,
• Feichen Cui,
• Yang Sui and
• Jiajun Yan

Beilstein J. Org. Chem. 2023, 19, 1580–1603, doi:10.3762/bjoc.19.116

• surface modification and radical generation [147][148]. It can even generate radicals on otherwise inert fluoropolymer surfaces [149]. Electrochemical reactions are another approach to generate radicals at polymer surfaces. Hydroxyl radicals generated via the electro-Fenton reaction from H2O2 in the

Selective and scalable oxygenation of heteroatoms using the elements of nature: air, water, and light

• Damiano Diprima,
• Hannes Gemoets,
• Stefano Bonciolini and
• Koen Van Aken

Beilstein J. Org. Chem. 2023, 19, 1146–1154, doi:10.3762/bjoc.19.82

• synthesis [17][18][19][20], although they are less commonly utilized than the other two functional groups. Over time, various synthetic protocols for oxygenation reactions have evolved. Initially, stoichiometric amounts of toxic oxidants were used, but now more sustainable oxidants such as H2O2 [21][22], O2