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

The effect of dark states on the intersystem crossing and thermally activated delayed fluorescence of naphthalimide-phenothiazine dyads

• Liyuan Cao,
• Xi Liu,
• Xue Zhang,
• Jianzhang Zhao,
• Fabiao Yu and
• Yan Wan

Beilstein J. Org. Chem. 2023, 19, 1028–1046, doi:10.3762/bjoc.19.79

• chromophores, which are coupled through a Buchwald–Hartwig coupling reaction (another NI-PTZ paper) [39]. The oxidation of the PTZ unit was readily performed by treatment with H2O2 as oxidant (Scheme 1). All compounds were obtained with satisfactory yields and the molecular structures were fully characterized

• synthesized by a modified literature method [43]. Compound NI-PTZ-F (36 mg, 0.074 mmol) was dissolved in glacial acetic acid (5 mL), H2O2 (1.5 mL, 30%, 1.184 mmol) was added dropwise and the mixture was stirred at 40 °C for 1 h. Then, the reaction mixture was poured into water and the pH of the mixture was

Photocatalytic sequential C–H functionalization expediting acetoxymalonylation of imidazo heterocycles

• Deepak Singh,
• Shyamal Pramanik and
• Soumitra Maity

Beilstein J. Org. Chem. 2023, 19, 666–673, doi:10.3762/bjoc.19.48

• produced in cycle-1 to give the acetoxy radical (∙OAc) and H2O2. Then, the radical recombination between AcO∙ and radical VI furnishes the desired product 4. In the absence of the acetoxy radical (∙OAc), the hydroperoxy radical (∙OOH) may combine with radical VI to produce VII, which then easily converts

An efficient metal-free and catalyst-free C–S/C–O bond-formation strategy: synthesis of pyrazole-conjugated thioamides and amides

• Shubham Sharma,
• Dharmender Singh,
• Sunit Kumar,
• Vaishali,
• Rahul Jamra,
• Naveen Banyal,
• Deepika,
• Chandi C. Malakar and
• Virender Singh

Beilstein J. Org. Chem. 2023, 19, 231–244, doi:10.3762/bjoc.19.22

• yield was observed (entries 2–5, Table 2). The oxidant TBHP (10 equiv) failed to deliver the anticipated product in good yield (36%, entry 6, Table 2). Similar results were obtained with H2O2 (25.0 equiv) under neat reaction conditions (entry 7, Table 2). Next, we performed the oxidative amidation

• reaction with 5.0 equiv of H2O2 in DMSO as the reaction medium under heating, whereas, a poor yield of the product was obtained (entry 8, Table 2). Moreover, different combinations of H2O2 and DMSO were examined for the oxidative amidation of pyrazole-3-carbaldehyde 1 (entries 9 and 10, Table 2

• ). Interestingly, a significant reduction in the reaction time was detected with 25 equiv as well as 10 equiv of H2O2. Next, we screened DMF, CH3CN, THF, and MeOH (2.0 equiv) with 10.0 equiv of H2O2 to increase the yield of the designed prototype 1F. An acceptable enhancement was observed in the yield of the

Improving the accuracy of ³¹P NMR chemical shift calculations by use of scaling methods

• William H. Hersh and
• Tsz-Yeung Chan

Beilstein J. Org. Chem. 2023, 19, 36–56, doi:10.3762/bjoc.19.4

• chemical shift of −181 ppm. Compound 32 underwent a stereospecific thermal [1,5]-sigmatropic rearrangement to bicyclic 33 exhibiting a 31P NMR chemical shift of −79 ppm. Pyrolysis of 33 at 480 °C gave isomeric 34 having a 31P NMR chemical shift of −14 ppm, while H2O2 oxidation of compounds 33 and 34 gave

Redox-active molecules as organocatalysts for selective oxidative transformations – an unperceived organocatalysis field

• Elena R. Lopat’eva,
• Igor B. Krylov,
• Dmitry A. Lapshin and
• Alexander O. Terent’ev

Beilstein J. Org. Chem. 2022, 18, 1672–1695, doi:10.3762/bjoc.18.179

• organocatalyst forms hydrogen bonds with both H2O2 and cyclic ketones [66]. A chiral Brønsted acid was used as chirality source and activator of H2O2 for an asymmetric sulfoxidation reaction [67] (Scheme 4B). It is generally accepted that in asymmetric Brønsted acid catalysis the activation of both the

• , the acidic and basic sites of the catalyst are suggested to be involved in the activation of only hydrogen peroxide within a well-defined and deep chiral cavity. The enantioselective approach of sulfide to H2O2 is ensured by the sterically demanding structure of the catalyst. It should also be noted

• active oxidative agent. Asymmetric quaternary ammonium phase-transfer catalysts proved to be effective in the asymmetric nucleophilic epoxidation of electron-poor alkenes by hydroperoxides [70] and the asymmetric hydroxylation of enolizable carbonyl compounds employing O2 or H2O2 as terminal oxidants [71

Naphthalimide-phenothiazine dyads: effect of conformational flexibility and matching of the energy of the charge-transfer state and the localized triplet excited state on the thermally activated delayed fluorescence

• Kaiyue Ye,
• Liyuan Cao,
• Davita M. E. van Raamsdonk,
• Zhijia Wang,
• Jianzhang Zhao,
• Daniel Escudero and
• Denis Jacquemin

Beilstein J. Org. Chem. 2022, 18, 1435–1453, doi:10.3762/bjoc.18.149

• dissolved in glacial acetic acid (28 mL), H2O2 (8.2 mL, 30%, 6.5 mmol) was added dropwise. The mixture was stirred at 40 °C overnight. The mixture was poured into water and the pH of the mixture was brought to 7 with a saturated aqueous solution of Na2CO3. After cooling, water (20 mL) was added, and the

• optimized ground state geometries. An isovalue of 0.02 is used. Synthesis of the compoundsa. aKey: (a) phenothiazine, sodium tert-butoxide, dried toluene (TOL), tri-tert-butylphosphine tetrafluoroborate, Pd(OAc)2, 120 °C, 8 h, 93.1%; (b) H2O2 (30%), CH3COOH, 40 °C, 1 h, yield: 87.2%; (c) similar to step (a

Inductive heating and flow chemistry – a perfect synergy of emerging enabling technologies

• Conrad Kuhwald,
• Sibel Türkhan and
• Andreas Kirschning

Beilstein J. Org. Chem. 2022, 18, 688–706, doi:10.3762/bjoc.18.70

• ) [93]. Cyclohexanone (25) was mixed with conc. formic acid, and a mixture of H2O2 (30%)/HNO3 (65%) in a PTFE reactor at rt. This led to the formation of the cyclic triperoxide 91 in 48% (isolated) yield. Interestingly, the equilibrium favors the formation of the trimer 91 over the corresponding dimeric

Menadione: a platform and a target to valuable compounds synthesis

• Acácio S. de Souza,
• Ruan Carlos B. Ribeiro,
• Dora C. S. Costa,
• Fernanda P. Pauli,
• David R. Pinho,
• Matheus G. de Moraes,
• Fernando de C. da Silva,
• Luana da S. M. Forezi and
• Vitor F. Ferreira

Beilstein J. Org. Chem. 2022, 18, 381–419, doi:10.3762/bjoc.18.43

• •−), hydrogen peroxide (H2O2), hydroxyl radical (•OH), and hydroperoxyl radical (•OOH) (Figure 3) [35]. Additionally, the menadione semiquinone radical can participate in another redox cycle, such as, the Fenton reaction, also resulting in the production of hydroxyl and hydroperoxyl radicals (Figure 3) [39][40

• one of the most studied and used oxidants has been H2O2. Yamaguchi and co-workers described the oxidation of 16 with aqueous H2O2 in the presence of a palladium(II)-polystyrene sulfonic acid resin (Table 1, entry 4) [50]. According to the authors, in the absence of the catalysts, the oxidation took

• place slowly with 7.8% yield, meanwhile, Pd-catalysis improved the yield to 50–60% under otherwise identical conditions [50]. The approach described by the Adam’s group used H2O2 (85%) and methyltrioxorhenium(VII) (MTO) as the catalyst (Table 1, entry 5) [51][64]. Without the catalyst, the reaction

Recent advances and perspectives in ruthenium-catalyzed cyanation reactions

• Thaipparambil Aneeja,
• Cheriya Mukkolakkal Abdulla Afsina,
• Padinjare Veetil Saranya and
• Gopinathan Anilkumar

Beilstein J. Org. Chem. 2022, 18, 37–52, doi:10.3762/bjoc.18.4

• -immobilized ruthenium trichloride to catalyze the oxidative cyanation of tertiary amines [28]. The reaction was performed using 2 mol % of catalyst, 2.5 mmol H2O2, 1.2 mmol NaCN, and 1 mL CH3COOH in methanol at room temperature (Scheme 1). Better yields of the α-aminonitrile products were obtained for

• -41-2N-RuCl3) catalyzed oxidative cyanation of tertiary amines was achieved by Cai et al. [31]. The optimized conditions were MCM-41-2N-RuCl3 (5 mol %), NaCN (1.2 mmol), AcOH (6.0 mmol), H2O2 (2.5 mmol) in methanol at 60 °C under Ar atmosphere for 4 h (Scheme 6). The reaction proceeded smoothly for N

• group reported a novel synthetic pathway for the oxidative cyanation of tertiary amines using sodium cyanide [33]. The optimized conditions for this reaction included the use of 0.05 mmol of RuCl3 as the catalyst, 1.2 mmol of NaCN in acetic acid as the cyanide source and 2.5 mmol of H2O2 as the oxidant

Efficient N-arylation of 4-chloroquinazolines en route to novel 4-anilinoquinazolines as potential anticancer agents

• Rodolfo H. V. Nishimura,
• Thiago dos Santos,
• Valter E. Murie,
• Luciana C. Furtado,
• Leticia V. Costa-Lotufo and
• Giuliano C. Clososki

Beilstein J. Org. Chem. 2021, 17, 2968–2975, doi:10.3762/bjoc.17.206

• and 8b. Conditions: a) NBS, CH3CN, 30 min, 25 °C; b) H2O, H2O2, I2, 24 h, 50 °C. N-Arylation reactions using ortho-, meta-, and para-substituted primary anilines of type 14 followed by methylation of ortho-derivatives 15a–d, to obtain the desired 4-anilinoquinazolines of type 10. N-Arylation reactions

Highly stereocontrolled total synthesis of racemic codonopsinol B through isoxazolidine-4,5-diol vinylation

• Lukáš Ďurina,
• Anna Ďurinová,
• František Trejtnar,
• Ľuboš Janotka,
• Lucia Messingerová,
• Jana Doháňošová,
• Ján Moncol and
• Róbert Fischer

Beilstein J. Org. Chem. 2021, 17, 2781–2786, doi:10.3762/bjoc.17.188

• phosphotungstic heteropoly acid, a commercial heteropoly acid [29][30]. Under our optimized conditions in terms of amount of catalyst, reaction temperature, and organic co-solvent, the epoxidation of 11 with aqueous H2O2 (35 wt %) and 12WO3·H3PO4×H2O (1 mol %) at room temperature in ethyl acetate provided the

• %; (c) 12WO3·H3PO4×H2O, H2O2 (35 wt % in H2O), pyridine, ethyl acetate, rt, 48 h, 70%; (d) BF3·OEt2, CH2Cl2, 0 °C, 15 min, 69%; (e) H2 (1 atm), Pd(OH)2/C (5 wt %), MeOH, rt, 2 h, (±)-2, 71%; (f) H2 (1 atm), Pd(OH)2/C (5 wt %), MeOH, rt, 2 h; then formaldehyde (37 wt % in H2O), H2 (1 atm), Pd(OH)2/C (5

Synthesis of highly substituted fluorenones via metal-free TBHP-promoted oxidative cyclization of 2-(aminomethyl)biphenyls. Application to the total synthesis of nobilone

• Ilya A. P. Jourjine,
• Lukas Zeisel,
• Jürgen Krauß and
• Franz Bracher

Beilstein J. Org. Chem. 2021, 17, 2668–2679, doi:10.3762/bjoc.17.181

• secondary and tertiary amines, amides/lactams/carbamates, and nitrile. The test reactions were monitored by thin-layer chromatography (TLC) and, where deemed necessary, results were further verified by GC–MS. The reagents employed encompassed tritylium tetrafluoroborate [50], H2O2/HBr [42], ceric ammonium

• nitrate (CAN) [41], 2,2,6,6-tetramethylpiperidinyloxyl (TEMPO)/CuCl [51], K2S2O8 [36], dimethyl sulfoxide (DMSO)/O2 [52], PhI(OAc)2/benzoyl peroxide (BPO) [47], Dess-Martin periodinane, N-bromosuccinimide (NBS), N-hydroxyphthalimide (NHPI)/Co(OAc)2/O2 [53], H2O2/tetrabutylammonium iodide (TBAI) [43], CBr4

Cryogels: recent applications in 3D-bioprinting, injectable cryogels, drug delivery, and wound healing

• Luke O. Jones,
• Leah Williams,
• Tasmin Boam,
• Martin Kalmet,
• Chidubem Oguike and
• Fiona L. Hatton

Beilstein J. Org. Chem. 2021, 17, 2553–2569, doi:10.3762/bjoc.17.171

On the application of 3d metals for C–H activation toward bioactive compounds: The key step for the synthesis of silver bullets

• Renato L. Carvalho,
• Amanda S. de Miranda,
• Mateus P. Nunes,
• Roberto S. Gomes,
• Guilherme A. M. Jardim and
• Eufrânio N. da Silva Júnior

Beilstein J. Org. Chem. 2021, 17, 1849–1938, doi:10.3762/bjoc.17.126

• usually mediated by V(V) and V(IV)-oxo-peroxo complexes, which are produced in situ from vanadium-oxo and dioxo precatalysts in the presence of oxidants, such as H2O2, O2, and tert-butyl hydroperoxide (TBHP) [76][77][78][79][80][81][82]. Inorganic acids and chelating and non-chelating carboxylic acids

• derivatives. Using H2O2 as an oxidant agent, ketones and aldehydes were obtained from hydrocarbons with high yields (85–99%, Scheme 9B and 9C). Although the authors did not explore the biological effects of the obtained products, this class of molecules resembles the basic structure of several important

Manganese/bipyridine-catalyzed non-directed C(sp³)–H bromination using NBS and TMSN₃

• Kumar Sneh,
• Takeru Torigoe and
• Yoichiro Kuninobu

Beilstein J. Org. Chem. 2021, 17, 885–890, doi:10.3762/bjoc.17.74

• alcohols with HBr, PBr3, or other brominating reagents [7][8][9][10][11][12][13]. Direct C–H halogenation is one of the most efficient methods used for the synthesis of halogenated organic molecules. This direct method involves the reaction of an alkane with Br2, CBr4, or H2O2–HBr under photolysis or at

Synthesis of bis(aryloxy)fluoromethanes using a heterodihalocarbene strategy

• Carl Recsei and
• Yaniv Barda

Beilstein J. Org. Chem. 2021, 17, 813–818, doi:10.3762/bjoc.17.70

• %. Synthesis of 1. Reagents and conditions: (a) 1,3-dibromo-5,5-dimethylhydantoin, benzoyl peroxide, (CH2Cl)2, reflux, 4 h, 88%; (b) 5,5-dimethyl-3-(4H-isoxazolyl) carbamimidothioate·HCl, K2CO3, MeCN/H2O, 50 °C, 1.5 h, 73%; (c) H2O2, Na2WO4, MeCN/H2O, 45 °C, 1.5 d, 66%. Synthesis of 11–13. Reagents and

A new and efficient methodology for olefin epoxidation catalyzed by supported cobalt nanoparticles

• Lucía Rossi-Fernández,
• Viviana Dorn and
• Gabriel Radivoy

Beilstein J. Org. Chem. 2021, 17, 519–526, doi:10.3762/bjoc.17.46

• solvent (DMF, MeCN, ethyl acetate, DMSO, solvent free) on the activity and selectivity of the nanocatalysts has been noted [27][41][42][43][44]. Furthermore, all the reported methodologies use either molecular oxygen together with an aldehyde as a co-reductant, or only a “green” peroxide (H2O2, TBHP) as

• the CuNPs supported on MgO as catalyst, but a similar result to that obtained in DMF was observed (Table 1, entry 5). The use of H2O2 as co-oxidant improved the conversion of the starting styrene (1a) only for the CoNPs/MgO catalyst, but lead to low selectivity due to the formation of benzaldehyde and