Recent advances in the electrochemical synthesis of organophosphorus compounds

• Babak Kaboudin,
• Milad Behroozi,
• Sepideh Sadighi and
• Fatemeh Asgharzadeh

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

• carried out in a divided cell using platinum electrodes as the anode and cathode in the presence of pyridine as a base and ligand (Scheme 14). The catalyst behavior of palladium is attributed to its ability to form palladium clusters of specific sizes that exhibit high catalytic activity. However, this

Entry to 2-aminoprolines via electrochemical decarboxylative amidation of N‑acetylamino malonic acid monoesters

• Olesja Koleda,
• Janis Sadauskis,
• Darja Antonenko,
• Edvards Janis Treijs,
• Raivis Davis Steberis and
• Edgars Suna

Beilstein J. Org. Chem. 2025, 21, 630–638, doi:10.3762/bjoc.21.50

• of N-o-nosyl-protected monoester 9g was performed in a divided cell in the presence of NaOH as a base (1 equiv). Gratifyingly, by this route N-o-nosyl-protected 6g was obtained in 25% yield. The attempted synthesis of 2-aminopipecolic acid derivative 6h under the developed conditions was unsuccessful

• amidation. aStainless-steel cathode; bgraphite cathode; cyield determined by 1H NMR using CH2Br2 as an internal standard; delectrolysis in divided cell with NaOH (1 equiv); ePt cathode; fwith KOH (1 equiv); gwith KOH (0.5 equiv); hperformed on 925 mg (2.7 mmol) scale. Synthetic modifications of 2

Electrochemical synthesis of cyclic biaryl λ³-bromanes from 2,2’-dibromobiphenyls

• Andrejs Savkins and
• Igors Sokolovs

Beilstein J. Org. Chem. 2025, 21, 451–457, doi:10.3762/bjoc.21.32

• −2 led to 60% λ3-bromane 1a degradation, suggesting that cationic 1a, formed on the anode, decomposes on the cathode. To avoid the undesired cathodic decomposition of 1a, the cathode and anode chambers were separated, and further experiments were performed in a divided cell. Gratifyingly, the change

• of the cell type allowed for more than a two-fold increase in the yield of product 1a from 28% (entry 2, undivided cell, Table 1) to 60% (entry 6, divided cell). Interestingly, higher amounts of passed charge did not improve the reaction outcome (Table 1, entry 7). Neither successful was also a

A review of recent advances in electrochemical and photoelectrochemical late-stage functionalization classified by anodic oxidation, cathodic reduction, and paired electrolysis

• Nian Li,
• Ruzal Sitdikov,
• Ajit Prabhakar Kale,
• Joost Steverlynck,
• Bo Li and
• Magnus Rueping

Beilstein J. Org. Chem. 2024, 20, 2500–2566, doi:10.3762/bjoc.20.214

• cathodic reduction and to prevent the reoxidation of the reduced SO2 at the anode, a divided cell setup is required (Scheme 12). C–H bond halogenation: Aryl and alkyl halides are important synthetic building blocks for cross-coupling reactions as well as bioactive molecules with applications in

• [73]. This approach minimizes the risk of adverse outcomes by utilizing cell potentials that are insufficient to oxidize the substrate directly, thus allowing selective one-electron oxidation by the electrophotocatalyst. A divided cell with a carbon felt anode and a platinum cathode is employed under

gem-Difluorination of carbon–carbon triple bonds using Brønsted acid/Bu₄NBF₄ or electrogenerated acid

• Mizuki Yamaguchi,
• Hiroki Shimao,
• Kengo Hamasaki,
• Keiji Nishiwaki,
• Shigenori Kashimura and
• Kouichi Matsumoto

Beilstein J. Org. Chem. 2024, 20, 2261–2269, doi:10.3762/bjoc.20.194

• −’’ equivalents might serve as good reagents for the gem-difluorination of alkynes. Thus, we have examined the electrochemical oxidation of a solution of Bu4NBF4/CH2Cl2 containing 1a (0.5 mmol) in a divided cell using 8 mA or 16 mA (Scheme 1, method B, in-cell method). In-cell method means that EGA was generated

Harnessing the versatility of hydrazones through electrosynthetic oxidative transformations

• Aurélie Claraz

Beilstein J. Org. Chem. 2024, 20, 1988–2004, doi:10.3762/bjoc.20.175

• conducted in a divided cell under potentiostatic conditions at 1.2–1.65 V vs SCE in acetonitrile. In 1976, the same group reported the anodic cyclization of chalcone-derived N-phenylhydrazone 3 to pyrazole 4 in a divided cell at constant current (Scheme 2) [37]. The obtained poor yield was explained by the

• -oxadiazolines 24b, respectively. Using sodium methoxide as basic supporting electrolyte in a divided cell equipped with carbon rod anodes and a platinium coil cathode, the transformation would involve cyclization of carbocationic species 25 to form the intermediate 26. From 23a (R2 = H), the latter would

• -tetraethylammonium perchlorate solution under constant potential in a divided cell equipped with platinum gauze anode and nickel cathode. Such a transformation constituted a straightforward route to the corresponding fused s-triazolo perchlorates 46 in moderate to high yield. Coulometric analysis established that

Additive-controlled chemoselective inter-/intramolecular hydroamination via electrochemical PCET process

• Kazuhiro Okamoto,
• Naoki Shida and
• Mahito Atobe

Beilstein J. Org. Chem. 2024, 20, 264–271, doi:10.3762/bjoc.20.27

• , entry 3); thus, the phosphate base plays a crucial role in N-alkylation, while its basicity is insufficient to promote aza-Michael addition (pKa of the conjugate acid of the phosphate base is 1.72 in H2O) [12]. Furthermore, N-alkylation proceeded in a divided cell (anodic chamber); thus, the possibility

• in vacuo and the resulting residue was subjected to 1H NMR spectroscopy or column chromatography. A divided-cell experiment was performed using an H-type cell (4G glass filter). Compound 1 (0.2 mmol), Bu4NPF6 (387 mg, 1 mmol), phosphate base (90 mg, 0.2 mmol), CH2Cl2 (10 mL), and methyl vinyl ketone

1-Butyl-3-methylimidazolium tetrafluoroborate as suitable solvent for BF₃: the case of alkyne hydration. Chemistry vs electrochemistry

• Marta David,
• Elisa Galli,
• Richard C. D. Brown,
• Marta Feroci,
• Fabrizio Vetica and
• Martina Bortolami

Beilstein J. Org. Chem. 2023, 19, 1966–1981, doi:10.3762/bjoc.19.147

• the 19F NMR analysis of BMIm-BF4 after anodic oxidation in a divided cell, which shows a peak at −147.3 ppm (besides the peak at −150.6 due to BF4−) (see Supporting Information File 1, Figure S1e), which is replaced by a peak at −144.0 ppm (referred to −150.6 ppm for BF4−) when the electrolysis is

• was set at −150.6 ppm in 19F NMR spectrum [112]. We thus carried out the anodic oxidation of pure BMIm-BF4 (divided cell, galvanostatic conditions) and stopped the electrolysis after 60 C (corresponding to 0.6 mmol of electrons). At the end of the electrolysis, 0.6 mmol of DIPEA were added to the

• oxidation of pure BMIm-BF4 (divided cell, galvanostatic conditions) and stopped the electrolysis after 60 C (corresponding to 0.6 mmol of electrons). At the end of the electrolysis, 0.6 mmol of DBU were added to the anolyte and the mixture was kept under stirring at room temperature for 30 min. Then the

Photoredox catalysis harvesting multiple photon or electrochemical energies

• Mattia Lepori,
• Simon Schmid and
• Joshua P. Barham

Beilstein J. Org. Chem. 2023, 19, 1055–1145, doi:10.3762/bjoc.19.81

Combining the best of both worlds: radical-based divergent total synthesis

• Kyriaki Gennaiou,
• Antonios Kelesidis,
• Maria Kourgiantaki and
• Alexandros L. Zografos

Beilstein J. Org. Chem. 2023, 19, 1–26, doi:10.3762/bjoc.19.1

• polyene 14 (prepared in two steps) in multigram quantities [23]. The reaction employed a divided cell with substoichiometric amounts of magnesium(II) acetate (0.5 equiv) and catalytic copper(II) 3,5-diisopropylsalicylate (0.02 equiv) to allow the redox radical cyclization of polyene in 42% yield. A Tsuji

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

• benzyl iodides generated in situ. Electrolysis conditions: Constant current electrolysis until anodic potential 1.12 V vs Fc/Fc+, divided cell, reticulated vitreous carbon (RVC) anode(+). Electrochemical oxidative C–O/C–N coupling of alkylarenes with NHPI. Electrolysis conditions: Constant current

Electrogenerated base-promoted cyclopropanation using alkyl 2-chloroacetates

• Kouichi Matsumoto,
• Yuta Hayashi,
• Kengo Hamasaki,
• Mizuki Matsuse,
• Hiyono Suzuki,
• Keiji Nishiwaki and
• Norihito Kawashita

Beilstein J. Org. Chem. 2022, 18, 1116–1122, doi:10.3762/bjoc.18.114

• -chloroacetates in Bu4NBr/DMF using a divided cell equipped with Pt electrodes to produce the corresponding cyclopropane derivatives in moderate yields were discovered. The reaction conditions were optimized, the scope and limitations, as well as scale-up reactions were investigated. The presented method for the

• electrochemical production of cyclopropane derivatives is an environmentally friendly and easy to perform synthetic procedure. Keywords: alkyl 2-chloroacetates; cyclopropane derivatives; divided cell; electro-reduction; Introduction In organic chemistry, cyclopropanes and their related compounds have been

• derivatives could be formed in moderate yields through the electrochemical reduction [13][14][15][16][17][18][19][20][21] of alkyl 2-chloroacetates in a divided cell (Scheme 1, reaction 4). The in Abushanab’s study utilized metal lithium is one of the rarest and most expensive metals. In addition, the

Electrochemical formal homocoupling of sec-alcohols

• Kosuke Yamamoto,
• Kazuhisa Arita,
• Masashi Shiota,
• Masami Kuriyama and
• Osamu Onomura

Beilstein J. Org. Chem. 2022, 18, 1062–1069, doi:10.3762/bjoc.18.108

• . The reported methods commonly carried out in a divided cell [29][30][31][32][33][34] or an undivided cell with sacrificial anodes [35], such as Al, Mg, and Sn, to prevent undesired oxidative reactions (Scheme 1b) [36][37][38][39]. While sacrificial anodes enable the reactions to be performed with a

Electrochemical Friedel–Crafts-type amidomethylation of arenes by a novel electrochemical oxidation system using a quasi-divided cell and trialkylammonium tetrafluoroborate

• Hisanori Senboku,
• Mizuki Hayama and
• Hidetoshi Matsuno

Beilstein J. Org. Chem. 2022, 18, 1040–1046, doi:10.3762/bjoc.18.105

• , Hokkaido 060-8628, Japan 10.3762/bjoc.18.105 Abstract Electrochemical Friedel–Crafts-type amidomethylation was successfully carried out by a novel electrochemical oxidation system using a quasi-divided cell and trialkylammonium tetrafluoroborates, such as iPr2NHEtBF4. Constant current electrolysis of

• 1,3,5-trimethoxybenzene or indoles in DMA containing 0.1 M iPr2NHEtBF4 using an undivided cell equipped with a Pt plate cathode and a Pt wire anode (a quasi-divided cell) resulted in selective formation of N-acyliminium ions of DMA at the anode, which reacted with arenes to give the corresponding

• amidomethylated products in good to high yields. Keywords: electrochemical oxidation; Friedel–Crafts type amidomethylation; N-acyliminium ion; quasi-divided cell; trialkylammonium salt; Introduction Oxidation of amides generates useful intermediates, N-acyliminium ions, which have been widely used in organic

First example of organocatalysis by cathodic N-heterocyclic carbene generation and accumulation using a divided electrochemical flow cell

• Daniele Rocco,
• Ana A. Folgueiras-Amador,
• Richard C. D. Brown and
• Marta Feroci

Beilstein J. Org. Chem. 2022, 18, 979–990, doi:10.3762/bjoc.18.98

• per l’Ingegneria, Sapienza University, via del Castro Laurenziano, 7, 00161, Rome, Italy 10.3762/bjoc.18.98 Abstract In this paper we present the first electrochemical generation of NHC carried out in a divided flow cell. The flow cell operated in the recycle mode. The need for a divided cell derived

• chamber (Figure 1). The requirement for a divided cell (a more complicated device than the undivided configuration) arises from the need to protect electrogenerated NHC from its anodic oxidation in the absence of a consumable anode. To ensure good sealing of the electrolysis cell, the sandwich-type

• arrangement of cell components was compressed between two end plates using a series of bolts. This design incorporated a solution inlet and a solution outlet for the chamber to allow uniform flow over the surface of the electrodes. In the present work, where a divided cell configuration was required, a proton

Electroreductive coupling of 2-acylbenzoates with α,β-unsaturated carbonyl compounds: density functional theory study on product selectivity

• Naoki Kise and
• Toshihiko Sakurai

Beilstein J. Org. Chem. 2022, 18, 956–962, doi:10.3762/bjoc.18.95

• ) was placed in the cathodic chamber of a divided cell (40 mL beaker, 3 cm diameter, 6 cm height) equipped with a platinum cathode (5 × 5 cm2), a platinum anode (2 × 1 cm2), and a ceramic cylindrical diaphragm (1.5 cm diameter). A 0.3 M solution of Bu4NClO4 in DMF (4 mL) was placed in the anodic chamber

A review of asymmetric synthetic organic electrochemistry and electrocatalysis: concepts, applications, recent developments and future directions

• Munmun Ghosh,
• Valmik S. Shinde and
• Magnus Rueping

Beilstein J. Org. Chem. 2019, 15, 2710–2746, doi:10.3762/bjoc.15.264

• ) in the kinetic resolution of primary amines 60 via their electrocatalytic oxidation to the corresponding ketones 62, and remaining amines (R)-60 were obtained with very high enantioselectivity. The controlled potential electrolysis was carried out in a divided cell in the presence of a base and a

Electrochemical Corey–Winter reaction. Reduction of thiocarbonates in aqueous methanol media and application to the synthesis of a naturally occurring α-pyrone

• Ernesto Emmanuel López-López,
• José Alvano Pérez-Bautista,
• Fernando Sartillo-Piscil and
• Bernardo A. Frontana-Uribe

Beilstein J. Org. Chem. 2018, 14, 547–552, doi:10.3762/bjoc.14.41

• An electrochemical version of the Corey–Winter reaction was developed giving excellent results in aqueous methanol media (MeOH/H2O (80:20) with AcOH/AcONa buffer 0.5 M as supporting electrolyte), using a reticulated vitreous carbon as cathode in a divided cell. The electrochemical version is much

C–H bond halogenation catalyzed or mediated by copper: an overview

• Wenyan Hao and
• Yunyun Liu

Beilstein J. Org. Chem. 2015, 11, 2132–2144, doi:10.3762/bjoc.11.230

• -workers [71] successfully achieved the selective mono-α-chlorination of β-keto esters/amides and 1,3-diketone 78 by employing an electrochemical synthesis via a catalysis by means of Cu(OTf)2. The synthesis of chlorinated carbonyl products 79 were acquired in a divided cell using aqueous HCl as chlorine

Electrochemical oxidation of cholesterol

• Jacek W. Morzycki and
• Andrzej Sobkowiak

Beilstein J. Org. Chem. 2015, 11, 392–402, doi:10.3762/bjoc.11.45

• transformed to 25-hydroxycholesterol (2) in 13% yield (Scheme 1). The statement that the Tl(II)/HMP/O2 adduct, suggested to be a radical in nature, is responsible for cholesterol oxidation was based on the following observations. The electrolysis performed in the divided cell indicated that the oxidation of

• converted into chlorohydrin 12 under the reaction conditions, which implies it was not formed through an epoxide intermediate. Finally, no products were formed when the electrolysis was performed in a divided cell. It seems that a chlorine species (e.g. Clδ+…FeCl4δ−), produced from anodically generated

• chlorine (dichloromethane was the likely source), initiated the sequence of reactions leading to cholesterol oxidation products. A very similar result was obtained by Kowalski et al. [39]. They carried out the electrolysis of cholesterol in dichloromethane by using a divided cell, the cathode of which was

Stereoselective cathodic synthesis of 8-substituted (1R,3R,4S)-menthylamines

• Carolin Edinger,
• Jörn Kulisch and
• Siegfried R. Waldvogel

Beilstein J. Org. Chem. 2015, 11, 294–301, doi:10.3762/bjoc.11.34

• that it can be efficiently converted to the corresponding diastereomeric amines with an excess of 3a in a divided cell under galvanostatic conditions employing an Hg pool cathode (see Scheme 2, pathway III) [26]. Here, we report a new synthetic route to optically pure 8-substituted menthylamines 1

• (6c and 7c, R2 = Ph) require prolonged reaction times and render slightly lower yields. Electrochemical reduction of 8-substituted menthone oximes The electrolyses were carried out in a divided cell using a Nafion® sheet as separator and platinum as anodic material. Since previous studies revealed

Switching the reaction pathways of electrochemically generated β-haloalkoxysulfonium ions – synthesis of halohydrins and epoxides

• Akihiro Shimizu,
• Ryutaro Hayashi,
• Yosuke Ashikari,
• Toshiki Nokami and
• Jun-ichi Yoshida

Beilstein J. Org. Chem. 2015, 11, 242–248, doi:10.3762/bjoc.11.27

• )-5-decene We first examined the reactions of β-bromoalkoxysulfonium ion 3a-Br generated by the reaction of (Z)-5-decene (2a) with Br+/DMSO (1-Br) [21] (Scheme 1, X = Br). Bu4NBr in DMSO/CH2Cl2 (1:9 v/v) was electrochemically oxidized at −78 °C in a divided cell using Bu4NBF4 as a supporting

• , X = I). Bu4NI in DMSO/CH2Cl2 (1:9 v/v) was electrochemically oxidized at −78 °C in a divided cell using Bu4NBF4 as a supporting electrolyte until 2.1 F/mol of electricity was applied. After addition of 2a to the solution, the mixture was stirred at 0 °C to give 3a-I, which was characterized by NMR

Cathodic reductive coupling of methyl cinnamate on boron-doped diamond electrodes and synthesis of new neolignan-type products

• Taiki Kojima,
• Rika Obata,
• Tsuyoshi Saito,
• Yasuaki Einaga and
• Shigeru Nishiyama

Beilstein J. Org. Chem. 2015, 11, 200–203, doi:10.3762/bjoc.11.21

• unprecedented neolignan-type dimeric compounds. Results and Discussion Cathodic reduction on BDD electrode The ester methyl cinnamate (1a) was electrolyzed under constant current electrolysis (CCE) conditions in a divided cell. Solvents used for the reactions played a significant role in providing the desired

Electrochemical selenium- and iodonium-initiated cyclisation of hydroxy-functionalised 1,4-dienes

• Philipp Röse,
• Steffen Emge,
• Jun-ichi Yoshida and
• Gerhard Hilt

Beilstein J. Org. Chem. 2015, 11, 174–183, doi:10.3762/bjoc.11.18

• iodoalkoxylated products of type 5 (Scheme 3). The electrolysis was carried out in an H-type divided cell (4G glass filter) equipped with carbon fiber electrodes (see Supporting Information File 1). Each chamber was charged with 2,6-lutidine and TBABF4 in CH3CN (0.3 M) and additionally the 1,4-dienol and sodium

• ), dried over Na2SO4 and the solvent was removed under reduced pressure. The product was obtained after column chromatography (n-pentane/diethyl ether). General procedure for the electrochemical iodonium-induced alkoxylation of 1,4-dienols An H-type divided cell (4G glass filter) was equipped with a carbon

Recent advances in the electrochemical construction of heterocycles

• Robert Francke

Beilstein J. Org. Chem. 2014, 10, 2858–2873, doi:10.3762/bjoc.10.303

• hydride in combination with a radical initiator such as AIBN. Peters and co-workers described an electrochemical alternative using cathodically generated nickel(I) complexes as mediators [41][42]. Under potentiostatic conditions (C.P.E. = controlled potential electrolysis) in a divided cell

• of the iminium species under formation of oxazolidine or 1,3-oxazinane species 30. According to their protocol, 29 is electrolyzed under galvanostatic conditions in a divided cell, using a NaOMe/MeOH electrolyte and potassium iodide as electron transfer mediator. The method provides access to a

• conventional Wacker-type cyclizations, where stoichiometric amounts of co-oxidant are employed at elevated temperatures, the electrochemical version proceeds smoothly at room temperature. In the case depicted in Scheme 16, the electrolysis was carried out in a divided cell under galvanostatic conditions using