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

• 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP) as an additive. These results provide fundamental insights for the design of PCET-based redox reaction systems under electrochemical conditions. Keywords: amidyl radical; cyclic voltammetry; electrosynthesis; hydroamination; proton coupled electron transfer

• 1. Detailed CV analysis indicated that the size of the hydrogen bond complex determined the selectivity, and HFIP played a crucial role in expanding the hydrogen bond network. These results provide fundamental insights beneficial for the design of PCET-based redox reaction systems under

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

• . Radicals can be generated by a broader selection of homogeneous and heterogeneous approaches, including hydrogen atom abstraction, decomposition of immobilized initiators, electrochemical redox reaction, or irradiation because the reactions only need to take place at the surface. Small-molecule oxidants

Microelectrode arrays, electrosynthesis, and the optimization of signaling on an inert, stable surface

• Kendra Drayton-White,
• Siyue Liu,
• Yu-Chia Chang,
• Sakashi Uppal and
• Kevin D. Moeller

Beilstein J. Org. Chem. 2022, 18, 1488–1498, doi:10.3762/bjoc.18.156

• associated electrodes resulting in a change in the ability of the electrode to either oxidize or reduce the group. This causes a change in the current measured for the redox reaction [14]. Alternatively, the binding event can be detected with an indirect, impedance-based method. This method works by

Chemical approaches to discover the full potential of peptide nucleic acids in biomedical applications

• Nikita Brodyagin,
• Martins Katkevics,
• Venubabu Kotikam,
• Christopher A. Ryan and
• Eriks Rozners

Beilstein J. Org. Chem. 2021, 17, 1641–1688, doi:10.3762/bjoc.17.116

Icilio Guareschi and his amazing “1897 reaction”

• Gian Cesare Tron,
• Alberto Minassi,
• Giovanni Sorba,
• Mara Fausone and
• Giovanni Appendino

Beilstein J. Org. Chem. 2021, 17, 1335–1351, doi:10.3762/bjoc.17.93

• ”, formally an internal redox reaction where the heterocyclic system is oxidatively aromatized and one of the substituents at C-4 reductively lost as a hydrocarbon. The reaction involves the treatment of a ketone with a solution of ethylcyanoacetate in ethanolic ammonia [7]. A precipitate of the ammonium salt

Insight into functionalized-macrocycles-guided supramolecular photocatalysis

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

Beilstein J. Org. Chem. 2021, 17, 139–155, doi:10.3762/bjoc.17.15

• macrocycle has inherent chromophores that can function as photosensitizers, the efficiency of the energy transfer will be higher and the systems will be simplified. 3) Other kinds of macrocycle-based catalysis need to be explored, such as esterification, polymerization, redox reaction, etc. 4) Hyperbranched

Activated carbon as catalyst support: precursors, preparation, modification and characterization

• Melanie Iwanow,
• Tobias Gärtner,
• Volker Sieber and
• Burkhard König

Beilstein J. Org. Chem. 2020, 16, 1188–1202, doi:10.3762/bjoc.16.104

Synthesis and properties of tetrathiafulvalenes bearing 6-aryl-1,4-dithiafulvenes

• Aya Yoshimura,
• Hitoshi Kimura,
• Kohei Kagawa,
• Mayuka Yoshioka,
• Toshiki Itou,
• Dhananjayan Vasu,
• Takashi Shirahata,
• Hideki Yorimitsu and
• Yohji Misaki

Beilstein J. Org. Chem. 2020, 16, 974–981, doi:10.3762/bjoc.16.86

• and 4 in the high potential region at +0.4 to +0.5 V were smaller than those of the simulated waves. This phenomenon might be understood by considering that electron transfer of this redox reaction was slow enough to become the rate-determining step because the crowded structure by which the TTF core

Rhodium-catalyzed reductive carbonylation of aryl iodides to arylaldehydes with syngas

• Zhenghui Liu,
• Peng Wang,
• Zhenzhong Yan,
• Suqing Chen,
• Dongkun Yu,
• Xinhui Zhao and
• Tiancheng Mu

Beilstein J. Org. Chem. 2020, 16, 645–656, doi:10.3762/bjoc.16.61

• concentrations of PPh3 both led to decreased yields (Table 4). This indicated that in the active catalytic species the molar ratio of [Rh]:PPh3 was exactly 1:3 (not 1:4 because of the consumption of 1 equiv PPh3 during the redox process), which might be Rh(PPh3)3Cl. The mentioned redox reaction can be explained

• reacted via a redox reaction to form Rh(PPh3)3Cl, which is the active catalytic species able to activate C–I bonds in the aryl iodides for the insertion of CO in the next step. The base Et3N neutralized the proton in the intermediate rhodium hydroiodide (D) complex and regenerated the active Rh species

Visible-light-induced addition of carboxymethanide to styrene from monochloroacetic acid

• Kaj M. van Vliet,
• Nicole S. van Leeuwen,
• Albert M. Brouwer and
• Bas de Bruin

Beilstein J. Org. Chem. 2020, 16, 398–408, doi:10.3762/bjoc.16.38

• rapid redox reaction between the oxidant and the reducing agent instead of converting the substrate). Excitation of the photocatalyst, on the other hand, allows continuous formation of low concentrations of both oxidized and reduced radical forms of the substrate(s), and the excited catalysts (and/or

The LANCA three-component reaction to highly substituted β-ketoenamides – versatile intermediates for the synthesis of functionalized pyridine, pyrimidine, oxazole and quinoxaline derivatives

• Tilman Lechel,
• Roopender Kumar,
• Mrinal K. Bera,
• Reinhold Zimmer and
• Hans-Ulrich Reissig

Beilstein J. Org. Chem. 2019, 15, 655–678, doi:10.3762/bjoc.15.61

• acetic anhydride at 90 °C furnished the expected pyrimidine derivative PM61 in 69% yield [32] showing that this transformation involves an internal redox reaction. However, the mechanism of this rearrangement is still under discussion [56][57] and side-products such as PM62 having a 4-ethyl group (3

Organometallic vs organic photoredox catalysts for photocuring reactions in the visible region

• Aude-Héloise Bonardi,
• Frédéric Dumur,
• Guillaume Noirbent,
• Jacques Lalevée and
• Didier Gigmes

Beilstein J. Org. Chem. 2018, 14, 3025–3046, doi:10.3762/bjoc.14.282

• named reduction agent, RA2 in Figure 1) by a redox reaction. In a reductive cycle, the PC* reacts first with a reduction agent (in Figure 1, RA1) which leads to PC●− and RA1●+. Then, PC can be regenerated with an oxidation agent (OA2). Radicals and cations are generated in these cycles [16]. As we can

Bioinspired cobalt cubanes with tunable redox potentials for photocatalytic water oxidation and CO₂ reduction

• Zhishan Luo,
• Yidong Hou,
• Jinshui Zhang,
• Sibo Wang and
• Xinchen Wang

Beilstein J. Org. Chem. 2018, 14, 2331–2339, doi:10.3762/bjoc.14.208

• electrochemical reduction. It is important to note that ligands with different electronic structures exhibited starkly different activities for redox reaction. The ligand with an electron-withdrawing property favors water oxidation, and the one with electron-donating property is conducive to CO2 reduction. Such a

Anomeric modification of carbohydrates using the Mitsunobu reaction

• Julia Hain,
• Patrick Rollin,
• Werner Klaffke and
• Thisbe K. Lindhorst

Beilstein J. Org. Chem. 2018, 14, 1619–1636, doi:10.3762/bjoc.14.138

• appropriate reagents for a Mitsunobu thioglycosylation. However, a competitive redox reaction with the PR3-azodicarboxylate reagent system precludes this application [79][80]. In spite of that, thioglycosides 111–113 could be prepared via a Mitsunobu-type condensation of thioglycosides such as 108 and 109

Polysubstituted ferrocenes as tunable redox mediators

• Sven D. Waniek,
• Jan Klett,
• Christoph Förster and
• Katja Heinze

Beilstein J. Org. Chem. 2018, 14, 1004–1015, doi:10.3762/bjoc.14.86

• (homogeneous). The benefit of the presence of a mediator is the switch of the sluggish heterogeneous electron transfer between electrode and substrate to a rapid homogeneous redox reaction between mediator and substrate. Further, the mediator’s redox potential must be below or above of that of the substrate

Recent progress in the racemic and enantioselective synthesis of monofluoroalkene-based dipeptide isosteres

• Myriam Drouin and
• Jean-François Paquin

Beilstein J. Org. Chem. 2017, 13, 2637–2658, doi:10.3762/bjoc.13.262

• ]. Indeed, triorganozincates (Me2(R)ZnMgX) were formed in situ and these reagents activated favourably the substrates towards the stereoselective addition of the alkyl chain. To prepare Boc-Val-ψ[(Z)-CF=CH]-Gly-OEt, Otaka’s group developed an intramolecular redox reaction of 3,3-difluoropropenes using N

• and co-workers. Synthesis of the tripeptide Boc-Asp(OBn)-Pro-ψ[(Z)-CF=CH)-Val-CH2OH by Miller and co-workers. Copper-catalyzed synthesis of monofluoralkenes by Taguchi and co-workers. One-pot intramolecular redox reaction to access amide-type isosteres by Otaka and co-workers. Copper-mediated

Dialkyl dicyanofumarates and dicyanomaleates as versatile building blocks for synthetic organic chemistry and mechanistic studies

• Grzegorz Mlostoń and
• Heinz Heimgartner

Beilstein J. Org. Chem. 2017, 13, 2235–2251, doi:10.3762/bjoc.13.221

• 97 were subjected to reactions with E-1a under the same reaction conditions, cyclic disulfides 98 were obtained as products of a redox reaction [72]. The analogous reaction course was observed with selenols, which were converted into the corresponding diselenides in good yields. The formation of

Sugar-based micro/mesoporous hypercross-linked polymers with in situ embedded silver nanoparticles for catalytic reduction

• Qing Yin,
• Qi Chen,
• Li-Can Lu and
• Bao-Hang Han

Beilstein J. Org. Chem. 2017, 13, 1212–1221, doi:10.3762/bjoc.13.120

• used as the supporting matrix to load AgNPs by treatment with Tollens’ reagent through a redox reaction (Scheme 2) [40]. After SugPOP-1 was stirred into the freshly prepared Tollens’ reagent solution at 45 °C for 24 h in the dark, the obtained composite was washed with water to remove soluble

From chemical metabolism to life: the origin of the genetic coding process

• Antoine Danchin

Beilstein J. Org. Chem. 2017, 13, 1119–1135, doi:10.3762/bjoc.13.111

• requirement would be that some catalysis allowed for a redox reaction (this is a general requirement of cell metabolism, involved in many metabolic steps, that is difficult, if not impossible, to fulfil using only RNA). As a consequence, primitive metabolic pathways would subsequently synthesise general

Polyketide stereocontrol: a study in chemical biology

• Kira J. Weissman

Beilstein J. Org. Chem. 2017, 13, 348–371, doi:10.3762/bjoc.13.39

• reduced product obtained by chemical synthesis, in which C-2 was deuterium labeled (i.e., [2-2H]-2-methyl-3-hydroxypentanoate); the substrate was tethered enzymatically to a model ACP domain sourced from the DEBS PKS. By incubating with NADP+, the redox reaction was run in reverse, establishing an

A versatile route to polythiophenes with functional pendant groups using alkyne chemistry

• Xiao Huang,
• Li Yang,
• Rikard Emanuelsson,
• Jonas Bergquist,
• Maria Strømme,
• Martin Sjödin and
• Adolf Gogoll

Beilstein J. Org. Chem. 2016, 12, 2682–2688, doi:10.3762/bjoc.12.265

• both EDOT-based oxidation and MV-centered reductions. The build-up of the MV-centered redox peaks is clearly evident at −0.8 V vs Fc+/Fc0 and −1.2 V vs Fc+/Fc0 corresponding to the MV2+/+ redox reaction and the MV+/0 redox reaction, respectively. The CVs of these polymers can be found in Supporting

A new paradigm for designing ring construction strategies for green organic synthesis: implications for the discovery of multicomponent reactions to build molecules containing a single ring

• John Andraos

Beilstein J. Org. Chem. 2016, 12, 2420–2442, doi:10.3762/bjoc.12.236

• to alternating nucleophilic-electrophilic connectivities and hence more direct synthesis routes; whereas, odd-membered rings often lead to connectivities between pairs of nucleophilic termini or pairs of electrophilic termini. This latter situation indicates that an extra redox reaction is a required

Lewis acid-catalyzed redox-neutral amination of 2-(3-pyrroline-1-yl)benzaldehydes via intramolecular [1,5]-hydride shift/isomerization reaction

• Chun-Huan Jiang,
• Xiantao Lei,
• Le Zhen,
• Hong-Jin Du,
• Xiaoan Wen,
• Qing-Long Xu and
• Hongbin Sun

Beilstein J. Org. Chem. 2014, 10, 2892–2896, doi:10.3762/bjoc.10.306

• : catalysis; C–H activation; hydride-shift; Lewis acid; redox reaction; Introduction The direct and selective functionalization of the inactive C(sp3)–H bond constitute an economically attractive strategy for organic syntheses [1][2][3][4][5][6][7][8][9][10]. Until now, a number of transition metals can be

• -alkylpyrroles could be formed via a redox isomerization reaction (Scheme 1, reaction 1) [34][35][36]. Moreover, we recently realized a Lewis acid-catalyzed intramolecular redox reaction using an aldehyde group as the H-shift acceptor to afford (2-(1H-pyrrol-1-yl)phenyl)methanol (Scheme 1, reaction 2) [37]. As

• requirement that the iminium formation reaction should be faster than the aldehyde redox reaction. Results and Discussion In our initial investigation, aldehyde 1a and dibenzylamine (2a) were chosen as the model reaction substrates. In the presence of 10 mol % PhCOOH, the reaction of 1a with 2a in DCE at rt

Tailoring of organic dyes with oxidoreductive compounds to obtain photocyclic radical generator systems exhibiting photocatalytic behavior

• Christian Ley,
• Julien Christmann,
• Ahmad Ibrahim,
• Luciano H. Di Stefano and
• Xavier Allonas

Beilstein J. Org. Chem. 2014, 10, 936–947, doi:10.3762/bjoc.10.92

• calculated Gibbs free energy of the dye regeneration redox reaction. These slightly endergonic values (0.42 and 0.12 eV) support the low kred and kox rate constants used for computation. The measured electron transfer rate constants are in line with the ΔG, confirming the low reactivity of 3PS toward EDB

Stability of SG1 nitroxide towards unprotected sugar and lithium salts: a preamble to cellulose modification by nitroxide-mediated graft polymerization

• Guillaume Moreira,
• Laurence Charles,
• Mohamed Major,
• Florence Vacandio,
• Yohann Guillaneuf,
• Catherine Lefay and
• Didier Gigmes

Beilstein J. Org. Chem. 2013, 9, 1589–1600, doi:10.3762/bjoc.9.181

• a solvent. The aim of the study was to measure the redox potentials of the SG1 and LiCl/solvent and to conclude if a redox reaction could happen between these species. The redox potentials of SG1 and LiCl (4.5 wt %) in DMF and MeOH were then determined by cyclic voltammetry with a platinum electrode

• redox reaction is the one involving the reduction of the in situ formed Cl2 to Cl− and the oxidation of the nitroxide to an oxoammonium ion. In conclusion, if Cl2 can be formed in the system, then the oxidation of the SG1 nitroxide is possible. However, this hypothesis is challenging to validate since