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Search for "electrolysis" in Full Text gives 105 result(s) in Beilstein Journal of Organic Chemistry.
Recent advances in oxidative radical difunctionalization of N-arylacrylamides enabled by carbon radical reagents
Beilstein J. Org. Chem. 2025, 21, 1207–1271, doi:10.3762/bjoc.21.98
- in a THF/MeOH solvent mixture, using a constant current electrolysis setup with a reticulated vitreous carbon (RVC) anode and a platinum cathode. The substrate scope was extensively investigated, and a broad array of N-aryl substituents was well tolerated, including electron-donating motifs such as
Recent advances in the electrochemical synthesis of organophosphorus compounds
Beilstein J. Org. Chem. 2025, 21, 770–797, doi:10.3762/bjoc.21.61
- dialkyl phosphonates at carbon and platinum electrodes as the anode and cathode in the presence of a silver catalyst in a divided cell (Scheme 3). According to the report, the silver catalyst is central to the coupling reaction. The study of the effect of alternating current (a.c.) electrolysis parameters
- a mononuclear palladacycle pathway, where a high electrolysis potential facilitates the formation of the ortho-phosphonate product with a favorable yield. On the other hand, when acid was used, forming a tetranuclear palladium intermediate led to the creation of a C−O−P bond. This reaction was
Entry to 2-aminoprolines via electrochemical decarboxylative amidation of N‑acetylamino malonic acid monoesters
Beilstein J. Org. Chem. 2025, 21, 630–638, doi:10.3762/bjoc.21.50
- monohydrolysis under basic conditions. The electrolysis proceeds in an undivided cell under galvanostatic control using low-cost graphite or stainless-steel electrodes, and the protocol was easily upscaled. Notably, an excellent diastereoselectivity (97:3 dr) could be achieved in the cyclization of a tethered
- ]. Accordingly, the electrolysis of monoester 9a in a 2:1 MeCN/H2O mixture in the presence of 0.025 M LiClO4 solution under constant current conditions (j = 12 mA/cm2) with graphite both as an anode and a cathode material afforded the desired N-tosylpyrrolidine 6a in 67% yield (Table 1, entry 1). The water
- feature at Ep = 1.78 V vs Ag/Ag+ (100 mV/s scan rate; see Figure 3A), and the electrolysis of pyrrolidine 6a under the optimized anodic decarboxylative cyclization conditions (entry 8, Table 1) afforded cyclic hemiaminal 12a (33% NMR yield), whose structure was proved by NMR experiments (Figure 3B). The
Electrochemical synthesis of cyclic biaryl λ3-bromanes from 2,2’-dibromobiphenyls
Beilstein J. Org. Chem. 2025, 21, 451–457, doi:10.3762/bjoc.21.32
- why the reaction appears as a one-electron oxidation in CV experiments, but still as a two-electron oxidation in electrolysis. Conclusion In conclusion, we have demonstrated a conceptual approach to cyclic diaryl λ3-bromanes by electrochemical oxidative cyclization of 2,2'-dibromo-1,1'-biphenyls. The
Oxidation of [3]naphthylenes to cations and dications converts local paratropicity into global diatropicity
Beilstein J. Org. Chem. 2025, 21, 277–285, doi:10.3762/bjoc.21.20
- conducted on a Cary 5000 spectrophotometer. A C3 epsilon potentiostat from BASi was used for the electrolysis using a thin layer cell from a demountable Specac® Omni cell. In this cell, a three-electrode system was coupled to conduct in situ spectroelectrochemistry. A Pt gauze and a Pt wire were used as
- working and counter electrodes, respectively. A Ag wire was employed as the pseudo-reference electrode in a 0.1 M solution of Bu4NPF6 in freshly distilled CH2Cl2. Sample concentration was 1 mM. The spectra were collected by constant potential electrolysis, and the potentials were changed in intervals of
Recent advances in electrochemical copper catalysis for modern organic synthesis
Beilstein J. Org. Chem. 2025, 21, 155–178, doi:10.3762/bjoc.21.9
- 2023, the Mei group reported the C(sp3)–H alkenylation of THIQs with acrolein by a combination of Cu/TEMPO and electrooxidation (Figure 6) [52]. CV experiments demonstrated that TEMPO was a suitable redox mediator, and on/off experiments confirmed that the reaction continued even without electrolysis
- . THIQ (13) was rapidly oxidized to an iminium intermediate under the action of electricity and oxygen. However, when the iminium intermediate was converted to the desired product 19, electrolysis had no effect, and this step proceeded more gradually than the initial oxidation step. Therefore, the
- optimized conditions allowed the reaction to proceed under a constant current electrolysis at 1.5 mA for 6 hours, followed by stirring for additional 24 hours with the electricity turned off. These reaction conditions were applicable to various N-aryl-THIQ derivatives with various functional groups. Using
Hypervalent iodine-mediated intramolecular alkene halocyclisation
Beilstein J. Org. Chem. 2024, 20, 3113–3133, doi:10.3762/bjoc.20.258
- Et3N·5HF. The in situ formation of this unstable HVI reagent avoided the requirement for it to be isolated. It was used either in a 1-step in-cell procedure with alkene, or in a 2-step, ex-cell approach [41], in which the substrate was added after the electrolysis, thereby avoiding any competing
Advances in the use of metal-free tetrapyrrolic macrocycles as catalysts
Beilstein J. Org. Chem. 2024, 20, 3085–3112, doi:10.3762/bjoc.20.257
- increasing addition of TsOH into 67, an increase in electrocatalytic current appeared before the second reduction wave, while the first reduction at −1.14 V remained unchanged, suggesting formation of radical anion [67]˙− as the first step. UV–vis spectroelectrochemical measurements under bulk electrolysis
- and tested them as HER electrocatalysts using acetic acid as an alternative proton source [124]. Preliminary results indicated that the biscorrole (1.5 mg, 1 μM) could produce 0.84 mL of H₂ during 1 hour of electrolysis, as confirmed by gas chromatography (GC). Villagrán and co-workers reported a
Advances in radical peroxidation with hydroperoxides
Beilstein J. Org. Chem. 2024, 20, 2959–3006, doi:10.3762/bjoc.20.249
Transition-metal-free synthesis of arylboronates via thermal generation of aryl radicals from triarylbismuthines in air
Beilstein J. Org. Chem. 2024, 20, 2577–2584, doi:10.3762/bjoc.20.216
- under transition-metal-free and open-air conditions. Conventional methods required photoirradiation or electrolysis to generate aryl radicals from triarylbismuthines. In this study, it was found that simply heating the solution of triarylbismuthines in benzotrifluoride (BTF) in air successfully led to
- of photocatalysts or UV light irradiation without metal catalysts [45][46][47][48]. Similar homolysis by electrolysis has also been reported [49]. These two activation methods required special equipment (i.e., light sources or electronic devices). To achieve thermal homolysis of the Ar–Bi bonds, the
A review of recent advances in electrochemical and photoelectrochemical late-stage functionalization classified by anodic oxidation, cathodic reduction, and paired electrolysis
Beilstein J. Org. Chem. 2024, 20, 2500–2566, doi:10.3762/bjoc.20.214
- representative examples to illustrate the potential of electrochemistry or photoelectrochemistry for the LSF of valuable molecular scaffolds. Keywords: electrochemistry; late-stage functionalization; paired electrolysis; pharmaceutical drugs; photoelectrochemistry; Introduction Organic electrochemistry is
- pharmaceutical drugs and natural products. We classify these advancements into three types: anodic oxidation, cathodic reduction, and paired electrolysis (Figure 1). This review considers direct electrolysis (oxidation or reduction), mediator-induced electrolysis, and metal-catalyzed and photocatalyzed
Visible-light-mediated flow protocol for Achmatowicz rearrangement
Beilstein J. Org. Chem. 2024, 20, 2493–2499, doi:10.3762/bjoc.20.213
- et al. [22] have demonstrated a combined use of flow and batch processes involving an electrochemical flow cell for the oxidation of furfuryl alcohols and subsequently utilizing the crude electrolysis mixture for hydrolysis in a traditional batch process to get the rearranged Achmatowicz product. As
Efficient one-step synthesis of diarylacetic acids by electrochemical direct carboxylation of diarylmethanol compounds in DMSO
Beilstein J. Org. Chem. 2024, 20, 2392–2400, doi:10.3762/bjoc.20.203
- , Japan 10.3762/bjoc.20.203 Abstract An efficient one-step synthesis of diarylacetic acids was successfully performed by electrochemical direct carboxylation of diarylmethanol compounds in DMSO. Constant-current electrolysis of diarylmethanol species in DMSO using a one-compartment cell equipped with a
- mandel acetates [14], respectively. Electrolysis of styrene oxide and related 2-phenylcyclic ethers in the presence of carbon dioxide also induced carboxylation at the benzylic position by reductive cleavage of a C(sp3)–O bond to give the corresponding ω-hydroxy-2-phenylalkanoic acids [15][16]. In
- constant-current electrolysis in DMF using an undivided cell equipped with a Pt cathode and a Mg anode in the presence of carbon dioxide. On the other hand, carboxylation scarcely took place in DMF when other benzyl alcohols were used as substrates. Lundberg and co-workers recently reported similar results
Synthesis, electrochemical properties, and antioxidant activity of sterically hindered catechols with 1,3,4-oxadiazole, 1,2,4-triazole, thiazole or pyridine fragments
Beilstein J. Org. Chem. 2024, 20, 2378–2391, doi:10.3762/bjoc.20.202
- participation of the catechol group in the first redox transition, the microelectrolysis of 3 was carried out at a controlled potential of 1.35 V in MeCN (2 h, 0.8 F/mol). After electrolysis, a decrease in the current intensity of the first oxidation peak is observed on the CVs of this compound (conversion
- reaches 51%). Besides, the current value of the second peak remains unchanged. In the cathodic region, a one-electron quasi-reversible peak is displayed (Epc = −0.58 V). This process corresponds to the reduction of o-benzoquinone to o-benzosemiquinone. During electrolysis, the color of the solution
- oxidation was confirmed during a controlled potential microelectrolysis of compound 6 at 1.30 V (2 h, 0.8 F/mol). A similar electrochemical picture is observed for electrolysis products of catechol 6 as in the case of catechol 3. The recorded absorption spectra after the electrolysis display an intense
gem-Difluorination of carbon–carbon triple bonds using Brønsted acid/Bu4NBF4 or electrogenerated acid
Beilstein J. Org. Chem. 2024, 20, 2261–2269, doi:10.3762/bjoc.20.194
- containing alkyne substrates could also give the corresponding gem-difluorinated compounds (in-cell method). The ex-cell electrolysis method was also applicable for gem-difluorination of alkynes. Keywords: carbon–carbon triple bonds; chemical method; electrochemistry; gem-difluorination; Introduction
- , and the substrate was added to the solution after the electrolysis. Optimized conditions and the result are described in Scheme 2. Namely, the electrochemical oxidation of a 0.3 M Bu4NBF4/CH2Cl2 solution (8 mL) at 0 °C using 32 mA generated and accumulated the EGA as the pool. An electricity of 6.0 F
- /mol based on 0.5 mmol was passed to the solution. In order to suppress the increase of the solution temperature under the electrolysis, the electrolysis was conducted at 0 oC. Then, the solution containing EGA was allowed to react with 1a (0.5 mmol) at 0 °C for 0.5 h, giving the corresponding product
Electrochemical allylations in a deep eutectic solvent
Beilstein J. Org. Chem. 2024, 20, 2217–2224, doi:10.3762/bjoc.20.189
- demonstrate efficient and near quantitative recovery of the metal by electrolysis after product extraction and this recovered metal can be used again for further allylations. Further efforts to improve the efficiency and enable catalytic metal use are underway. Experimental Preparation of deep eutectic
- first analyzed by 1H NMR spectroscopy and then purified using flash column chromatography. The graphite electrodes were not polished in between reactions, but were rinsed with DI water and then acetone. DES and tin metal recycling For the recyclability trials, the electrolysis vial was opened and about
- and DES layers separate, the methoxycyclopentane layer was removed using a pipette, placed into a round-bottomed flask, and concentrated in vacuo. This remaining DES could be used directly in subsequent reactions. If SnCl2 was used in the reaction, electrolysis of the tin metal could be achieved after
Harnessing the versatility of hydrazones through electrosynthetic oxidative transformations
Beilstein J. Org. Chem. 2024, 20, 1988–2004, doi:10.3762/bjoc.20.175
- miscellaneous compounds. For reactions carried out under constant current electrolysis, the reported current applied (in A or mA) is depicted. Additionally, when possible, and for better accuracy, the current density (in mA·cm−2) has been calculated based on the size of the electrode portion immersed in the
- cyclization of 2-acetylpyridine-derived N-phenylhydrazone 1a to form triazolopyridinium salt 2a [34]. The process was further applied to various 2-acetylpyridine and 2-benzoylpyridine derivatives (Scheme 1) [35][36]. The corresponding pyridinium salts 2 were obtained in high yields when the electrolysis was
- . documented the synthesis of 1H-indazoles 9 via the electrooxidative cyclization of (hetero)aromatic ketones-derived N-phenylhydrazones 8 (Scheme 3) [38]. In contrast with the above-mentioned works, the electrolysis was carried out in an undivided cell under galvanostatic conditions. High yields were obtained
Novel oxidative routes to N-arylpyridoindazolium salts
Beilstein J. Org. Chem. 2024, 20, 1906–1913, doi:10.3762/bjoc.20.166
- negative potentials. The pyridoindazolium salt reduction is also sensitive to the presence of a base since the electron transfer is followed by a protonation chemical step. Indeed, a bulk electrolysis of amine A1 in the presence of 2,6-lutidine gave much better (60%) yield of salt S1. Additionally, the
- electrolysis potential was decreased (since lutidine facilitates amines’ oxidation): the starting potential was set as 1.0 V and was gradually increased to 1.4 V. The attempt to perform the electrolysis in a one-compartment cell was unsuccessful: the yield of the salt dropped to 38%. Thus, the optimized
- conditions of the potentiostatic electrolysis were the following: a two-compartment cell, a glassy carbon (GC) anode, DMF, the potential increased from 1.0 V to 1.4 V vs Ag/AgCl, KCl(sat.)), 2 F per mol of amine electricity passed, sodium tosylate (0.1 M) as a supporting electrolyte, and 2 equiv of 2.6
Synthesis of polycyclic aromatic quinones by continuous flow electrochemical oxidation: anodic methoxylation of polycyclic aromatic phenols (PAPs)
Beilstein J. Org. Chem. 2024, 20, 1746–1757, doi:10.3762/bjoc.20.153
- directed our efforts toward recirculating the reaction mixture through the cell several times. This is often necessary to enhance the conversion of the electrochemical oxidation [46][47]. An increased electrolysis time is necessary as the conversion rate decreases significantly with the decay of the
New triazinephosphonate dopants for Nafion proton exchange membranes (PEM)
Beilstein J. Org. Chem. 2024, 20, 1623–1634, doi:10.3762/bjoc.20.145
- exchange membrane devices [5][6], such as proton exchange membrane fuel cells (PEMFCs) [3][7][8][9], due to their high-power density and high power-to-weight ratio, and CO2 electrolysers, which can reduce the polluting gas CO2 and produce syngas from the co-electrolysis of CO2 and water [10][11], or water
Electrocatalytic hydrogenation of cyanoarenes, nitroarenes, quinolines, and pyridines under mild conditions with a proton-exchange membrane reactor
Beilstein J. Org. Chem. 2024, 20, 1560–1571, doi:10.3762/bjoc.20.139
- for a supporting electrolyte, which is necessary for conventional organic electrolysis, reduces the environmental impact, and facilitates product purification. In addition, using nanoparticles in the catalyst layer, which serve as the electrode, results in a large specific surface area and efficient
- , entry 2). Pt/C afforded the best result (90% current efficiency, Table 3, entry 3). To increase the yield, the reaction was carried out until 4a was consumed. After 7 h of electrolysis (23.2 F mol−1), 4a was completely consumed and 5a was obtained in 82% yield. Although Ir/C was inefficient (Table 3
- of the nitroarene electro-reduction was explored (Scheme 3). To obtain products in high yields, the electrolysis was performed until the substrates were consumed. First, nitroarenes bearing electron-donating groups were investigated. Nitroarenes 4b–d bearing methyl groups gave the corresponding
Benzylic C(sp3)–H fluorination
Beilstein J. Org. Chem. 2024, 20, 1527–1547, doi:10.3762/bjoc.20.137
- ·2HF proved to be the best of the HF·amine reagents screened. The reaction was conducted under constant potential conditions, using cyclic voltammetry prior to electrolysis to determine the appropriate oxidation potential required for each substrate. Under these conditions, yields of up to 65% were
- prolonged reaction times or upon increasing the applied cell potentials. In 2024, Lennox and co-workers reported their investigation in exploring how alternative electrolysis waveforms might assist in the generation of reactive primary benzylic cations for nucleophilic fluorination (Figure 43) [104]. The
- challenge involved avoiding over-oxidation of the monofluorination product and overcoming mass transportation issues. It was found that the use of pulsed electrolysis waveforms, via the introduction of resting periods during electrolysis, was beneficial for the reaction outcome. This was demonstrated on a
Electrophotochemical metal-catalyzed synthesis of alkylnitriles from simple aliphatic carboxylic acids
Beilstein J. Org. Chem. 2024, 20, 1497–1503, doi:10.3762/bjoc.20.133
- -known to be highly susceptible to electroplating on the cathode and thus require the use of ligands to avoid detrimental cathode deposition during electrolysis (Table 1, entry 3). In addition, we discovered that the additional use of DMF as co-solvent is beneficial to the reaction efficiency–reactions
- using acetonitrile as the solvent frequently led to the observation of Cu deposition at cathode (Table 1, entry 4). We reasoned that DMF could coordinate to the copper center, acting as a ligand to prevent copper from cathode reduction. Constant current electrolysis is also applicable to the reaction
- , the corresponding alkylnitrile product was obtained in 86% yield after electrolysis at 3.0 mA for 4 hours, demonstrating the high Faradaic efficiency of the reaction (Table 1, entry 5) [46]. Control experiments revealed that Ce catalyst, Cu catalyst, light, and electricity were all essential for the
Synthesis of cyclic β-1,6-oligosaccharides from glucosamine monomers by electrochemical polyglycosylation
Beilstein J. Org. Chem. 2024, 20, 1421–1427, doi:10.3762/bjoc.20.124
- electrolysis cell. Thioglycoside 14 (0.40 mmol, 186 mg), Bu4NOTf (1.0 mmol, 393 mg), DTBMP (2.0 mmol, 411 mg), and dry CH2Cl2 (10 mL) were added to the anodic chamber. Triflic acid (0.4 mmol, 35 μL) and CH2Cl2 (10 mL) were added to the cathodic chamber. Electrolysis was performed at −20 °C under constant
Auxiliary strategy for the general and practical synthesis of diaryliodonium(III) salts with diverse organocarboxylate counterions
Beilstein J. Org. Chem. 2024, 20, 1020–1028, doi:10.3762/bjoc.20.90
- ) carboxylate 7aj carrying a fluorescent-labeling group in 93% yield. Iodosoarenes 5b–f can be easily obtained by treating (dichloroiodo)arenes [41] or (diacetoxyiodo)arenes [42] with sodium hydroxide, by oxidation of iodoarenes with NaClO·5H2O [43], or by electrolysis [44]. The reaction scope of iodosoarenes
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