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Search for "electrochemistry" in Full Text gives 114 result(s) in Beilstein Journal of Organic Chemistry.
Size-controlled and redox-responsive supramolecular nanoparticles
Beilstein J. Org. Chem. 2015, 11, 2388–2399, doi:10.3762/bjoc.11.260
- electrochemistry [18] or by adding an oxidizing agent [19]. Different studies have employed this concept to form redox-responsive systems applied, for example, in self-healing materials [19], polymeric hydrogels [20][21], voltage-responsive vesicles [22], ultrasentive enzyme sensors [23], and as a plasma membrane
Polythiophene and oligothiophene systems modified by TTF electroactive units for organic electronics
Beilstein J. Org. Chem. 2015, 11, 1749–1766, doi:10.3762/bjoc.11.191
- (TTF and PT) inhibits any electrochemical activity from the polymer backbone and the electrochemistry of the material is dominated by the TTF unit. The inhibition of the polymer backbone’s electrochemical activity was confirmed by spectroelectrochemistry of 39, which indicated no change of the π–π
- state spectrum of the chemically synthesised sexithiophene 51; this is evidence of a strong π–π stacking interaction upon aggregation in the solid state. The electrochemistry of compound 51 is similar for both solution and solid state samples, with the main feature being the overlap between the second
- properties of 54 (n = 0–2) are shown in Table 4. The optical properties of 54 (n = 0–2) in solution (Table 4) follow a general trend of decreasing the absorption onset, while increasing the conjugation length. The electrochemistry of each H-shaped system 54 (n = 0–2) on the other hand is not so
Thiazole-induced rigidification in substituted dithieno-tetrathiafulvalene: the effect of planarisation on charge transport properties
Beilstein J. Org. Chem. 2015, 11, 1148–1154, doi:10.3762/bjoc.11.129
- the influence of favourable S–N interactions contributes to a more planar structure. The S and N atoms are separated by a distance of 3.01 Å, 0.34 Å shorter than the sum of the van der Waals radii of the two atoms (3.35 Å). In the electrochemistry section of this paper we discussed how the S–N
A hybrid electron donor comprising cyclopentadithiophene and dithiafulvenyl for dye-sensitized solar cells
Beilstein J. Org. Chem. 2015, 11, 1052–1059, doi:10.3762/bjoc.11.118
- unit. Keywords: donor–acceptor systems; dye-sensitized solar cells; electrochemistry; intramolecular charge transfer; Knoevenagel reaction; tetrathiafulvalene; Introduction Dye-sensitized solar cells (DSSCs) have been intensively investigated as an alternative to silicon-based solar cells [1][2][3][4
Glycoluril–tetrathiafulvalene molecular clips: on the influence of electronic and spatial properties for binding neutral accepting guests
Beilstein J. Org. Chem. 2015, 11, 1023–1036, doi:10.3762/bjoc.11.115
- Synthesis Molecular clips 1–3 [18] and 4 [19] were synthesized according to our previous reports. Electrochemical and spectroelectrochemical experiments Electrochemistry and time-resolved spectroelectrochemistry in solution were performed using the already described home self-made cell [44][45
- sensitivity of the spectroscopic measurement (<3 electrons at 100 kHz and <13 electrons at 2 MHz between 320 and 1080 nm; 400 electrons (high gain) and 5000 electrons (low gain) between 900 nm and 1700 nm) allows performing a spectroelectrochemistry experiment under the usual conditions of electrochemistry
Electrosynthesis and electrochemistry
Beilstein J. Org. Chem. 2015, 11, 949–950, doi:10.3762/bjoc.11.105
- Siegfried R. Waldvogel Institute for Organic Chemistry, Johannes Gutenberg University Mainz, Duesbergweg 10–14, 55128 Mainz, Germany 10.3762/bjoc.11.105 Keywords: chemical method; electrochemistry; electrosynthesis; sustainability; Since the pioneering work of Kolbe, electrochemistry and
- , electrochemistry is mostly taught by physical chemists, which seems to create a natural barrier to preparative organic applications. However, the systematic use of cationic species as intermediates to avoid over-oxidation establishes new ways for functionalization of substrates and paves the way to novel synthetic
Interactions between tetrathiafulvalene units in dimeric structures – the influence of cyclic cores
Beilstein J. Org. Chem. 2015, 11, 930–948, doi:10.3762/bjoc.11.104
- absorptions of 1b and 6 signal the stronger acceptor strength of radiaannulene cores (lower-lying LUMOs) relative to an acyclic TEE unit. This effect was also confirmed by electrochemistry (vide infra). Interestingly, compound 7 containing a diethynylpyridine acceptor unit exhibits the most redshifted
- absorption of all the compounds at λmax 779 nm (ε 210 M−1cm−1), but of significantly lower intensity than the charge-transfer absorptions of the TEE compounds. Electrochemistry The redox properties of the TTF-bridge-TTF molecules were investigated by cyclic voltammetry and differential pulse voltammetry in
- CH2Cl2 (0.1 M Bu4NPF6). For clarity we have broken the discussion of the electrochemistry into two sections, the first being the oxidation of the TTFs and their electronic interactions in comparison to related examples in the literature. The other section deals with the reduction of the molecules
Tuning of tetrathiafulvalene properties: versatile synthesis of N-arylated monopyrrolotetrathiafulvalenes via Ullmann-type coupling reactions
Beilstein J. Org. Chem. 2015, 11, 860–868, doi:10.3762/bjoc.11.96
- , both in solid state as well as in solution. MPTTF derivatives are readily soluble in non-polar organic solvents, such as CH2Cl2, toluene or acetone (with the exception of poorly soluble 4c), giving solutions that are stable at room temperature in air. Electrochemistry Solution oxidation potentials of
Trifluoromethyl-substituted tetrathiafulvalenes
Beilstein J. Org. Chem. 2015, 11, 647–658, doi:10.3762/bjoc.11.73
- dyads with a strong pairing of the radical species in a singlet state. Keywords: electrochemistry; electron withdrawing group (EWG); fluorine; tetrathiafulvalene (TTF); Introduction Following three decades of extensive work toward the elaboration of conducting radical cation salts from
Highly selective generation of vanillin by anodic degradation of lignin: a combined approach of electrochemistry and product isolation by adsorption
Beilstein J. Org. Chem. 2015, 11, 473–480, doi:10.3762/bjoc.11.53
- acidification and precipitation of remaining lignin. The latter represents a significant advantage compared with conventional work-up protocols of lignin solutions. Keywords: adsorption; electrochemistry; lignin; nickel; renewable resources; Introduction The biopolymer lignin is one of the most abundant and
- metal catalysts they commonly disappear in the unreacted lignin contaminating that particular material which limits further subsequent use. Electrochemistry is one of the most promising approaches for highly sustainable conversions because only electrons serve as reagent [21][22][23][24][25][26][27
Photovoltaic-driven organic electrosynthesis and efforts toward more sustainable oxidation reactions
Beilstein J. Org. Chem. 2015, 11, 280–287, doi:10.3762/bjoc.11.32
- Bichlien H. Nguyen Robert J. Perkins Jake A. Smith Kevin D. Moeller Washington University in Saint Louis, Saint Louis, Missouri 63130, United States 10.3762/bjoc.11.32 Abstract The combination of visible light, photovoltaics, and electrochemistry provides a convenient, inexpensive platform for
- . Keywords: electrochemistry; sustainable oxidation reactions; visible light; Introduction Organic electrochemistry is an extremely versatile tool for conducting a wide variety of chemical reactions [1][2][3]. This versatility stems from both the gentle, acid/base neutral reaction conditions employed for
- the reactions and the adjustable potential of the working electrode that enables the oxidation and reduction of substrates that often greatly differ in their electronic structure. It is particularly easy to take advantage of the opportunities electrochemistry offers when conducting constant current
Cathodic reductive coupling of methyl cinnamate on boron-doped diamond electrodes and synthesis of new neolignan-type products
Beilstein J. Org. Chem. 2015, 11, 200–203, doi:10.3762/bjoc.11.21
- -type products were synthesized from the hydrodimer. Keywords: boron-doped diamond (BDD) electrode; cathodic reduction; electrochemistry; electrosynthesis; neolignan; Introduction Numerous lignans and neolignans were found as secondary plant metabolites, and many of them are known to exhibit
Electrochemical selenium- and iodonium-initiated cyclisation of hydroxy-functionalised 1,4-dienes
Beilstein J. Org. Chem. 2015, 11, 174–183, doi:10.3762/bjoc.11.18
- and pyran derivatives under indirect electrochemical conditions generating selenium or iodonium cations. The reactions proceed in good yields and regioselectivities for the formation of single diastereomers. Keywords: cyclic ethers; cyclisation; 1,4-dienes; electrochemistry; iodonium; selenium
- antibacterial properties [10][11][12][13]. For this purpose, we investigated a protocol for the straight forward synthesis of 1,4-dienols which should be cyclised into the corresponding tetrahydrofuran or pyran derivatives. With our sight set on efficient and atom economic organic reactions electrochemistry
- seems to be a powerful tool for the transformation of those 1,4-dienols. Although it seems that all possible functional groups have been investigated in organic electrochemistry, reports on electrochemical transformations of 1,4-dienes are rare [14][15][16][17]. First attempts of a direct
The Shono-type electroorganic oxidation of unfunctionalised amides. Carbon–carbon bond formation via electrogenerated N-acyliminium ions
Beilstein J. Org. Chem. 2014, 10, 3056–3072, doi:10.3762/bjoc.10.323
- electroorganic techniques and future directions. Keywords: anodic oxidation; electrochemistry; electroorganic, electrosynthesis, N-acyliminium ions; natural products; non-Kolbe oxidation; peptidomimetics; Shono oxidation; synthesis; Review N-Acyliminium ions are synthetically versatile N-Acyliminium ions [1][2
- ) [76][77]. The ability to introduce two carbon–carbon bonds on to the same α-carbon to prepare spirocyclic systems is a challenge, yet the application of electrochemistry in tandem with ring closing metathesis (RCM) readily achieved this feat. The use of the Shono-type electrooxidation in natural
- ]. Examples of Phe7–Phe8 mimics prepared using an electrochemical approach [93]. Preparation of arginine mimics employing an electrooxidation step [96]. Preparation of chiral cyclic amino acids [20]. Two-step preparation of Nazlinine 117 using Shono flow electrochemistry [101]. Acknowledgements The authors
Recent advances in the electrochemical construction of heterocycles
Beilstein J. Org. Chem. 2014, 10, 2858–2873, doi:10.3762/bjoc.10.303
- reactions is presented and discussed in this review. Keywords: anodic cyclization; electrosynthesis; heterocycle; olefin coupling; organic electrochemistry; radical cyclization; Introduction The construction of heterocyclic cores undoubtedly represents a highly important discipline of organic synthesis
- electrochemistry of heterocyclic compounds are also available [27][28][29]. However, recent innovations in electrosynthesis such as the cation pool method or the development of novel electron transfer mediators also have a significant impact on heterocyclic chemistry [30][31]. This review focuses upon both anodic
- , electrochemistry represents a complementary method to conventional synthesis, due to unique selectivity and the possibility for electrochemical Umpolung. However, considering the fact that heterocycle-containing compounds represent the major part of active ingredients in pharmaceutics and crop protection, a lack
Synthesis and properties of novel star-shaped oligofluorene conjugated systems with BODIPY cores
Beilstein J. Org. Chem. 2014, 10, 2704–2714, doi:10.3762/bjoc.10.285
- generally increased with increasing molecular weight. This trend was most pronounced for Y-Bn (n = 1–4) and not so significant for the T-Bn (n = 1–4) series. In the latter case the Tg reached a saturation value at 99 °C for terfluorene T-B3. Electrochemistry The electrochemical properties of the materials
Molecular ordering at electrified interfaces: Template and potential effects
Beilstein J. Org. Chem. 2014, 10, 2243–2254, doi:10.3762/bjoc.10.233
- other hand the electrochemistry of viologens in solution is well documented in the literature [11][12]. In dicationic form dibenzyl-viologen molecules (DBV2+) are well-known to undergo two successive reversible electron transfer steps yielding first the corresponding monocation radical DBV+• and then
Scalable synthesis of 5,11-diethynylated indeno[1,2-b]fluorene-6,12-diones and exploration of their solid state packing
Beilstein J. Org. Chem. 2014, 10, 2122–2130, doi:10.3762/bjoc.10.219
- anticipated, altering the trialkylsilyl group has very little effect on the optoelectronic properties of the conjugated scaffold (Table 2). All molecules have two strong absorptions around 310 and 330 nm, with a much weaker, broad absorption in the 450–550 nm range. Electrochemistry shows two reversible
The Ugi four-component reaction as a concise modular synthetic tool for photo-induced electron transfer donor-anthraquinone dyads
Beilstein J. Org. Chem. 2014, 10, 1006–1016, doi:10.3762/bjoc.10.100
- constants of the solvent applied in spectroscopy (εs) and reference solvent used in electrochemistry (εref), and r+ and r− are indicating the effective ionic radii of the donor radical cation and acceptor radical anion, respectively. It is allowed to neglect the forth term, if spectroscopic and
Tuning the interactions between electron spins in fullerene-based triad systems
Beilstein J. Org. Chem. 2014, 10, 332–343, doi:10.3762/bjoc.10.31
- -fullerene spacing. The shorter oxalate-bridged triads exhibit stronger spin–spin coupling with triplet character, while in the longer terephthalate-bridged triads the intramolecular spin–spin coupling is significantly reduced. Keywords: carbon nanomaterials; electrochemistry; EPR; fullerene dimers
- restrict our discussion to dianionic species in compounds where the electrochemistry is well defined; under these conditions each fullerene cage is reduced by a single electron. We have evaluated the effects of varying the inter-fullerene separation (oxalate bridge vs terephthalate bridge) and the nature
The chemistry of amine radical cations produced by visible light photoredox catalysis
Beilstein J. Org. Chem. 2013, 9, 1977–2001, doi:10.3762/bjoc.9.234
- ; Introduction Amine radical cations, which are an odd-electron species, are of great utility in amine syntheses [1][2][3][4][5][6][7][8]. They can be formed by loss of an electron from the corresponding amines. This one-electron oxidation process has been realized by using electrochemistry [9][10][11], chemical
Self-assembly of 2,3-dihydroxycholestane steroids into supramolecular organogels as a soft template for the in-situ generation of silicate nanomaterials
Beilstein J. Org. Chem. 2013, 9, 1826–1836, doi:10.3762/bjoc.9.213
- , electrochemistry, light-harvesting materials and so on [1][2][3][4][5][6]. These small molecules self-assemble into regular supramolecular structures through non covalent interactions such as ion–ion, dipole–dipole, hydrogen bonding, π–π stacking, van der Waals, host–guest, and ion coordination, and in so doing
Incorporation of perfluorohexyl-functionalised thiophenes into oligofluorene-truxenes: synthesis and physical properties
Beilstein J. Org. Chem. 2013, 9, 1243–1251, doi:10.3762/bjoc.9.141
- electrochemistry and stability, as well as the improved chemical resistance and thermal stability that replacing alkyl hydrogen atoms with fluorine atoms affords [13]. Our group has previously published work on oligofluorene-functionalised truxenes [14], and it was in our interest to observe changes in the optical
Synthesis, photophysical and electrochemical characterization of terpyridine-functionalized dendritic oligothiophenes and their Ru(II) complexes
Beilstein J. Org. Chem. 2013, 9, 866–876, doi:10.3762/bjoc.9.100
- . Photophysical studies of the complexes revealed broad absorption spectra covering from 250 to 600 nm and high molar extinction coefficients. The MLCT emission of these complexes were significantly red-shifted (up to 115 nm) compared to the parent [Ru(tpy)2]2+ complex. Keywords: dendrons; electrochemistry
Spectroscopic characterization of photoaccumulated radical anions: a litmus test to evaluate the efficiency of photoinduced electron transfer (PET) processes
Beilstein J. Org. Chem. 2013, 9, 800–808, doi:10.3762/bjoc.9.91
- aromatic compounds known to participate in photosubstitution or photocatalytic alkylation reactions. It was proposed to ascertain whether these may accumulate, as often observed in electrochemistry [33][34] and by pulse radiolysis [35], but rarely in photochemistry. Results The acceptors chosen for this
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