Search results

Search for "electron transfer" in Full Text gives 327 result(s) in Beilstein Journal of Organic Chemistry. Showing first 200.

Direct C2–H alkylation of indoles driven by the photochemical activity of halogen-bonded complexes

  • Martina Mamone,
  • Giuseppe Gentile,
  • Jacopo Dosso,
  • Maurizio Prato and
  • Giacomo Filippini

Beilstein J. Org. Chem. 2023, 19, 575–581, doi:10.3762/bjoc.19.42

Graphical Abstract
  • charge transfer state which results in a bathochromic shift of the absorption towards the visible range [19][20]. Upon light irradiation, the EDA complex may undergo an intramolecular single-electron-transfer (SET) process to produce a radical ion pair (D•+, A•−). To avoid the occurrence of a back
  • -electron-transfer (BET), a suitable leaving group (LG) needs to be included in one of the precursors. In this manner, reactive intermediates (e.g., radical species) may be generated in solution through the irreversible fragmentation of the substrates [15][21][22]. These intermediates eventually react to
PDF
Album
Supp Info
Letter
Published 27 Apr 2023

A new oxidatively stable ligand for the chiral functionalization of amino acids in Ni(II)–Schiff base complexes

  • Alena V. Dmitrieva,
  • Oleg A. Levitskiy,
  • Yuri K. Grishin and
  • Tatiana V. Magdesieva

Beilstein J. Org. Chem. 2023, 19, 566–574, doi:10.3762/bjoc.19.41

Graphical Abstract
  • fragment in the oxidized (GlyNi)L7 and (ΔAlaNi)L7 complexes bears a certain spin density (as it has been previously shown for the t-Bu-free analogs [31]), the bulky t-Bu substituent does prevent dimerization of the radical cations formed in the electron-transfer step increasing their kinetic stability
  • reversibility can be reached at scan rates above 20 V/s allowing the E1/2 estimation. Similarly to previously studied complex (ΔAlaNi)L1 [36], electron transfer to (ΔAlaNi)L7 is mainly ligand centered. The DFT-estimated LUMO is formed as an overlap of the π antibonding orbitals of the dehydroalanine and imine
PDF
Album
Supp Info
Full Research Paper
Published 27 Apr 2023

CuAAC-inspired synthesis of 1,2,3-triazole-bridged porphyrin conjugates: an overview

  • Dileep Kumar Singh

Beilstein J. Org. Chem. 2023, 19, 349–379, doi:10.3762/bjoc.19.29

Graphical Abstract
  • -dipolar cycloaddition reaction between an azide and a terminal alkyne, also popular as "click reaction" or CuAAC reaction. Moreover, the 1,2,3-triazole ring also serves as a spacer and an electron transfer bridge between the porphyrin and the attached chromophores. In order to provide a critical overview
  • a photophysical investigation, a weak interaction was observed between two subunits at ground state in porphyrin-ferrocene dyads. Also, the fluorescence of porphyrin was significantly quenched in porphyrin-ferrocene conjugates due to photoinduced electron transfer from ferrocene to porphyrin
  • fluorescence investigation of hybrid 96 revealed that the fluorescence of zinc porphyrin was strongly quenched, and the electron-transfer quenching mechanism was validated by easy oxidation. Furthermore, femtosecond transient-absorption spectrum investigations offered proof of the charge-separation process
PDF
Album
Review
Published 22 Mar 2023

NaI/PPh3-catalyzed visible-light-mediated decarboxylative radical cascade cyclization of N-arylacrylamides for the efficient synthesis of quaternary oxindoles

  • Dan Liu,
  • Yue Zhao and
  • Frederic W. Patureau

Beilstein J. Org. Chem. 2023, 19, 57–65, doi:10.3762/bjoc.19.5

Graphical Abstract
  • run in a similar fashion to related well-documented previous reports [54][68][69][70][71][72][73][74][75][76][77], through a light-induced, phosphine-assisted, intermolecular electron transfer from sodium iodide to the redox-active ester. Conclusion In summary, we developed an effective photocatalytic
PDF
Album
Supp Info
Letter
Published 16 Jan 2023

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

Graphical Abstract
  • led to common scaffolds 47 and diene 48 after subsequent elimination. Those molecules serve as templates for Ni-based radical-based sp3–sp2 coupling and single-electron transfer (SET)-based [3 + 2] coupling, respectively (Scheme 4). Initial attempts to realize the [3 + 2] radical coupling with CAN led
  • radical to circumvent the unsuccessful Friedel–Crafts reaction. Prior reports implicated β-keto radical formation in the ring opening of siloxycyclopropanes with photoinduced electron transfer (PET) to 1,4-dicyanonaphthalene [65]. Inspired by reports on dual photoredox and Ni-catalytic cross-coupling
PDF
Album
Review
Published 02 Jan 2023

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

Graphical Abstract
  • unfavorable (DABCO, quinuclidine) and in the case of triarylamines containing no hydrogen atoms at carbon atoms connected to the cation radical center. Cation radicals of aromatic amines or N-heterocyclic cation radicals are usually involved in electron transfer processes due to their low affinity to hydrogen
  • mainly as mediators of oxidative electron transfer (SET mechanism). For example, one-electron oxidative properties of triarylamine cation radicals were used for the vinylarene difunctionalization with the formation of thiadiazolidine 1,1-dioxides that can be further transformed to the corresponding 1,2
  • via a SET mechanism. The first electron transfer occurs from the aromatic system to the organocatalyst cation radical. After the deprotonation of the benzylic position a benzylic radical is formed. Then, a benzylic cation is produced by a second oxidative electron transfer followed by nucleophile
PDF
Album
Perspective
Published 09 Dec 2022

Molecular and macromolecular electrochemistry: synthesis, mechanism, and redox properties

  • Shinsuke Inagi and
  • Mahito Atobe

Beilstein J. Org. Chem. 2022, 18, 1505–1506, doi:10.3762/bjoc.18.158

Graphical Abstract
  • /bjoc.18.158 Keywords: electron transfer; electrosynthesis; organic electrochemistry; redox-active materials; Electrochemistry is now a powerful tool in organic chemistry not only for analyzing the electron transfer behavior of organic molecules and macromolecules, but also for driving organic
  • , polymer electrolyte membrane electrolysis technology, and new methods coupled with photoredox catalysts or transition metal catalysis, resulting in remarkable progress in organic electrosynthetic processes. Theoretical calculations have also led to a better understanding of the electron transfer behavior
  • batteries. By understanding organic electron transfer reactions, we can face the challenge of how to design materials with better cycle properties by suppressing undesired side reactions. To showcase this area of research, the present thematic issue focuses on the recent advances in molecular and
PDF
Editorial
Published 26 Oct 2022

Cytochrome P450 monooxygenase-mediated tailoring of triterpenoids and steroids in plants

  • Karan Malhotra and
  • Jakob Franke

Beilstein J. Org. Chem. 2022, 18, 1289–1310, doi:10.3762/bjoc.18.135

Graphical Abstract
  • electron transfer from a reductase partner protein (step 2). The most common electron donors in plants are cytochrome P450 reductases which employ NADPH for the electron transfer, but several other electron transfer systems are known [22]. The reduced ferrous intermediate C, bearing an overall negative
PDF
Album
Supp Info
Review
Published 21 Sep 2022

Thermally activated delayed fluorescence (TADF) emitters: sensing and boosting spin-flipping by aggregation

  • Ashish Kumar Mazumdar,
  • Gyana Prakash Nanda,
  • Nisha Yadav,
  • Upasana Deori,
  • Upasha Acharyya,
  • Bahadur Sk and
  • Pachaiyappan Rajamalli

Beilstein J. Org. Chem. 2022, 18, 1177–1187, doi:10.3762/bjoc.18.122

Graphical Abstract
  • developed mainly by focusing on photophysical processes, such as photoinduced electron transfer (PET), excited-state intramolecular proton transfer (ESIPT), fluorescence resonance energy transfer (FRET), etc. [21][22][24][25]. Several literature reports have also demonstrated the switching of fluorescence
PDF
Album
Supp Info
Full Research Paper
Published 08 Sep 2022

Radical cation Diels–Alder reactions of arylidene cycloalkanes

  • Kaii Nakayama,
  • Hidehiro Kamiya and
  • Yohei Okada

Beilstein J. Org. Chem. 2022, 18, 1100–1106, doi:10.3762/bjoc.18.112

Graphical Abstract
  • to be much more effective in the reaction than other cycloalkanes. Since the reaction is completed with a substoichiometric amount of electricity, a radical cation chain pathway is likely to be involved. Keywords: arylidene cycloalkane; Diels–Alder reaction; radical cation; single-electron transfer
  • ; spiro ring system; Introduction Single-electron transfer is one of the simplest modes for small molecule activation, employing a polarity inversion to generate radical ions which have proven to be unique reactive intermediates in the field of synthetic organic chemistry. A radical cation Diels–Alder
  • reaction is a typical example of this activation mode since both the original diene and dienophile are electron-rich and thus not an effective combination of reactants [1][2][3][4][5][6][7][8][9][10][11]. Single-electron transfer makes the construction of six-membered ring systems possible. In general
PDF
Album
Supp Info
Letter
Published 25 Aug 2022

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

Graphical Abstract
  • from the corresponding vic-1,2-diol. Water may play a role as a proton source to facilitate the formation of the protonated ketyl radical through a concerted proton-electron transfer toward the ketone or smooth protonation of the radical anion species, which readily dimerize to vic-1,2-diol 2a [46][49
PDF
Album
Supp Info
Letter
Published 22 Aug 2022

Cathodic generation of reactive (phenylthio)difluoromethyl species and its reactions: mechanistic aspects and synthetic applications

  • Sadanobu Iwase,
  • Shinsuke Inagi and
  • Toshio Fuchigami

Beilstein J. Org. Chem. 2022, 18, 872–880, doi:10.3762/bjoc.18.88

Graphical Abstract
  • place. Thus, it was found that o-phthalonitrile should work as an electron transfer catalyst, i.e., a redox mediator. On the bases of the cyclic voltammetric measurements, the cathodic reduction of 1 was carried out at a constant potential using o-phthalonitrile as mediator. As shown in Scheme 5, the
  • one- and two-electron transfer, their indirect cathodic reduction using mediators undergoes one-electron reduction selectively as reported by Saveant et al. [24]. In this study, we also confirmed that the o-phthalonitrile-mediated reduction of PhSCF2Br (1) in the absence of radical trapping reagents
PDF
Album
Supp Info
Full Research Paper
Published 20 Jul 2022

Complementarity of solution and solid state mechanochemical reaction conditions demonstrated by 1,2-debromination of tricyclic imides

  • Petar Štrbac and
  • Davor Margetić

Beilstein J. Org. Chem. 2022, 18, 746–753, doi:10.3762/bjoc.18.75

Graphical Abstract
  • also found in the reaction of bicyclo[2.2.2] dibromide 42 (Scheme 3), which suggests that the mechanism may involve radical anion intermediates. This result further supports a single electron transfer (SET) and radical anion mechanism which was postulated earlier for the Zn/Ag debromination reaction
PDF
Album
Supp Info
Full Research Paper
Published 24 Jun 2022

Structural basis for endoperoxide-forming oxygenases

  • Takahiro Mori and
  • Ikuro Abe

Beilstein J. Org. Chem. 2022, 18, 707–721, doi:10.3762/bjoc.18.71

Graphical Abstract
  • the water addition occurs on the C3' carbocation, which is generated by one electron transfer to the ferric iron from the C3' radical intermediate (carbocation mechanism in Scheme 9). Notably, in this last step, the stereochemistry of the hydroxylation reaction is regulated by the enzyme to be the R
PDF
Album
Review
Published 21 Jun 2022

Direct C–H amination reactions of arenes with N-hydroxyphthalimides catalyzed by cuprous bromide

  • Dongming Zhang,
  • Bin Lv,
  • Pan Gao,
  • Xiaodong Jia and
  • Yu Yuan

Beilstein J. Org. Chem. 2022, 18, 647–652, doi:10.3762/bjoc.18.65

Graphical Abstract
  • -electron transfer (SET) between CuBr and intermediate 5 forms intermediate 6, which initiates the N–O bond homolytic cleavage resulting in forming an N-centred phthalimidyl radical 7 (PhthN•) and anion 8. Meanwhile, Cu(I) is oxidized to Cu(II) in this step. Next, radical 7 attacks the benzene via radical
PDF
Album
Supp Info
Letter
Published 03 Jun 2022

Tetraphenylethylene-embedded pillar[5]arene-based orthogonal self-assembly for efficient photocatalysis in water

  • Zhihang Bai,
  • Krishnasamy Velmurugan,
  • Xueqi Tian,
  • Minzan Zuo,
  • Kaiya Wang and
  • Xiao-Yu Hu

Beilstein J. Org. Chem. 2022, 18, 429–437, doi:10.3762/bjoc.18.45

Graphical Abstract
  • donor absorbs light energy and changes to the excited state (TPEWP5G*) energy level. Through energy transfer from TPEWP5G* to ground state EsY the latter undergoes excitation to the excited state EsY* and is reduced by the Hantzsch ester to generate the radical anion EsY•−. Subsequently, electron
  • transfer from EsY•− to the substrate α-bromoacetophenone (1a) gives the corresponding acetophenone radical, whilst EsY•− is oxidized to EsY. The acetophenone radical combines with a H-atom abstracted from the radical cation of the Hantzsch ester to form acetophenone (2a) as the final product and diethyl
PDF
Album
Supp Info
Full Research Paper
Published 13 Apr 2022

Synthesis of piperidine and pyrrolidine derivatives by electroreductive cyclization of imine with terminal dihaloalkanes in a flow microreactor

  • Yuki Naito,
  • Naoki Shida and
  • Mahito Atobe

Beilstein J. Org. Chem. 2022, 18, 350–359, doi:10.3762/bjoc.18.39

Graphical Abstract
  • , organic electrosynthetic reactions, which are driven by direct electron transfer to and from the electrodes, can produce highly reactive species under ambient conditions without the use of harmful and precious chemicals. Therefore, electrosynthesis has been actively researched in recent years as a green
PDF
Album
Supp Info
Full Research Paper
Published 29 Mar 2022

Earth-abundant 3d transition metals on the rise in catalysis

  • Nikolaos Kaplaneris and
  • Lutz Ackermann

Beilstein J. Org. Chem. 2022, 18, 86–88, doi:10.3762/bjoc.18.8

Graphical Abstract
  • underdeveloped. This lack of viable catalysis strategies involving 3d transition metals is largely due to a limited knowledge on the working mode of these metal catalysts, which often involve single-electron-transfer-based redox events. As a consequence, there is a strong demand for efficient and reliable
PDF
Editorial
Published 07 Jan 2022

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

Graphical Abstract
  • metal. Ruthenium complexes have astonishing characteristics such as high electron transfer ability, low redox potentials, high Lewis acidity, and greater stabilities of the reactive metallic species like oxometals, metallacycles, and metal carbene complexes [27]. The wide availability of highly reactive
PDF
Album
Review
Published 04 Jan 2022

DABCO-promoted photocatalytic C–H functionalization of aldehydes

  • Bruno Maia da Silva Santos,
  • Mariana dos Santos Dupim,
  • Cauê Paula de Souza,
  • Thiago Messias Cardozo and
  • Fernanda Gadini Finelli

Beilstein J. Org. Chem. 2021, 17, 2959–2967, doi:10.3762/bjoc.17.205

Graphical Abstract
  • (CF3)ppy]2(dtbbpy)PF6. SET = single-electron transfer event. Optimization of reaction conditionsa. Supporting Information Supporting Information File 324: General information, synthetic procedures, additional optimization and mechanistic results, NMR spectra and characterization of compounds and
PDF
Album
Supp Info
Letter
Published 21 Dec 2021

Iron-catalyzed domino coupling reactions of π-systems

  • Austin Pounder and
  • William Tam

Beilstein J. Org. Chem. 2021, 17, 2848–2893, doi:10.3762/bjoc.17.196

Graphical Abstract
  • which will react further. However, reactions catalyzed by the Lewis-acidic character of iron salts are beyond the scope of this review. Iron also has the ability to transfer one or two electrons to a substrate. This opens the possibility for radical reactions via a single electron transfer (SET). Once
PDF
Album
Review
Published 07 Dec 2021

Visible-light-mediated copper photocatalysis for organic syntheses

  • Yajing Zhang,
  • Qian Wang,
  • Zongsheng Yan,
  • Donglai Ma and
  • Yuguang Zheng

Beilstein J. Org. Chem. 2021, 17, 2520–2542, doi:10.3762/bjoc.17.169

Graphical Abstract
  • state is transformed to the lowest-energy triplet MLCT state, which has a sufficient lifetime for initiating single-electron transfer. In the triplet species, the electron in the higher singly occupied molecular orbital (SOMO) is transferred from RuII* to an external acceptor (A), thereby yielding
  • alkyl halides 14, olefins, and trifluoromethylthiolate 15. Mechanistic studies demonstrated that the photoexcited CuI/binap/SCF3 complex generated in situ engages in electron transfer with the alkyl halides, thereby providing an alkyl radical and the CuII/binap/SCF3 species. Subsequently, the alkyl
  • Functionalization of organic halides As demonstrated by the different photoredox mechanisms of Cu complexes, the CuI complexes have strong reduction ability and can promote electron transfer to organic substrates. Thus, the high reduction potentials of CuI complexes are also applied to the functionalization of
PDF
Album
Review
Published 12 Oct 2021

Exfoliated black phosphorous-mediated CuAAC chemistry for organic and macromolecular synthesis under white LED and near-IR irradiation

  • Azra Kocaarslan,
  • Zafer Eroglu,
  • Önder Metin and
  • Yusuf Yagci

Beilstein J. Org. Chem. 2021, 17, 2477–2487, doi:10.3762/bjoc.17.164

Graphical Abstract
  • [34][38][39][40]. The use of 2D materials for the photoinitiated electron transfer reactions with CuII catalysts for the photoinduced atom transfer radical polymerization (ATRP) and CuAAC reactions prompted us to develop a new photoredox system that works under NIR irradiation for the CuAAC reaction
  • reaction with Alk-4 gave higher yields with both light sources. In the light of previous studies, a photoinduced electron transfer mechanism presented in Scheme 1 can be proposed. Upon the light irradiation, BPNs absorb the light and generate a single electron which was transferred from the conduction band
PDF
Album
Supp Info
Full Research Paper
Published 23 Sep 2021

Photoredox catalysis in nickel-catalyzed C–H functionalization

  • Lusina Mantry,
  • Rajaram Maayuri,
  • Vikash Kumar and
  • Parthasarathy Gandeepan

Beilstein J. Org. Chem. 2021, 17, 2209–2259, doi:10.3762/bjoc.17.143

Graphical Abstract
  • under visible light irradiation at 35 °C (Scheme 15) [67]. Here, the diaryl ketone photocatalyst played a dual role as hydrogen-atom-transfer (HAT) and electron-transfer agent. This C–H arylation protocol provided the diarylmethane derivatives 26 in moderate to good yields. In 2019, the Hashmi group
PDF
Album
Review
Published 31 Aug 2021

Chemical syntheses and salient features of azulene-containing homo- and copolymers

  • Vijayendra S. Shetti

Beilstein J. Org. Chem. 2021, 17, 2164–2185, doi:10.3762/bjoc.17.139

Graphical Abstract
  • -shifted in comparison to azulene-fluorene polymers because of the electron transfer from the azulene to benzothiadiazole units. The optical (2.19–2.38 eV) and electrochemical (2.25–2.40 eV) band gaps for the polymers 136–138 were in good agreement with each other and the gap decreased with an increase in
  • 141–144 was low compared to all-azulene-carbazole polymer 140 due to the electron transfer from azulene to benzothiadiazole and, due to this, they exhibited better electrochromism. An electrochromic device (ECD) constructed with polymer 143 exhibited black to transmissive electrochromism with high
PDF
Album
Review
Published 24 Aug 2021
Other Beilstein-Institut Open Science Activities