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Search for "conductivity" in Full Text gives 94 result(s) in Beilstein Journal of Organic Chemistry.
Recent advances in the electrochemical synthesis of organophosphorus compounds
Beilstein J. Org. Chem. 2025, 21, 770–797, doi:10.3762/bjoc.21.61
- lower efficiency (e.g., some electrolytic cells). Role of electrolytes in organic electrochemical reactions Electrolytes are crucial for conductivity and reaction stability in organic electrochemical reactions. They are categorized as supporting electrolytes, which enhance conductivity, reduce
- was performed. The use of graphite and RVC gave good results. Nickel, graphite, and platinum electrodes were examined as the cathodes. Results showed that platinum and nickel performed better than graphite in the cathode due to their higher conductivity and lower electrical resistance. When platinum
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
- systems in which charge defects are responsible for conductivity in their corresponding conducting polymers. Acenes are the archetypal structure of small polycyclic aromatic hydrocarbons with a π-electron structure expanded over a sequence of linearly fused benzenes [4]. Whereas acenes, up to substituted
Effect of substitution position of aryl groups on the thermal back reactivity of aza-diarylethene photoswitches and prediction by density functional theory
Beilstein J. Org. Chem. 2025, 21, 242–252, doi:10.3762/bjoc.21.16
- Molecular photoswitches have been studied for a long time because their physicochemical properties such as refractive index [1][2], dipole moment [3][4], conductivity [5][6], magnetism [7][8], and fluorescence [9][10][11] can be spatiotemporally modulated by light without physical contact. Therefore
The charge transport properties of dicyanomethylene-functionalised violanthrone derivatives
Beilstein J. Org. Chem. 2024, 20, 2921–2930, doi:10.3762/bjoc.20.244
- properties of violanthrone is traced back to 1950, when Akamatu and Inokuchi measured its electrical conductivity (σ), which was found to be 3.4 × 10−4 Ω−1 cm−1 [27][28]. The chemical structure of violanthrone allows for its modification and hence the synthesis of materials with interesting spectral
5th International Symposium on Synthesis and Catalysis (ISySyCat2023)
Beilstein J. Org. Chem. 2024, 20, 2704–2707, doi:10.3762/bjoc.20.227
- values in the range of 1–10 μM. Teixeira et al. reported the preparation of new triazinephosphonate-based dopants and their application in the production of Nafion proton exchange membranes, which exhibited higher conductivity with only 1 wt % loading [19]. These new triazinephosphonate dopants could
Applications of microscopy and small angle scattering techniques for the characterisation of supramolecular gels
Beilstein J. Org. Chem. 2024, 20, 2608–2634, doi:10.3762/bjoc.20.220
- structures formed by the self-assembly of amino acid-appended perylene bisimides (PBIs) [83]. They found that the average fibre length was a critical nanostructural feature for affording a desirable mechanoresponsive property, that is the change in conductivity under a bending force, in PBI films. Therefore
Electrochemical radical cation aza-Wacker cyclizations
Beilstein J. Org. Chem. 2024, 20, 1900–1905, doi:10.3762/bjoc.20.165
- due to the increased conductivity of the electrolyte solution (Table 1, entry 1). The reaction did not take place without electricity and most of the starting material was recovered (Table 1, entry 3). The addition of trifluoroacetic acid (TFA) was advantageous in terms of the reproducibility, which
New triazinephosphonate dopants for Nafion proton exchange membranes (PEM)
Beilstein J. Org. Chem. 2024, 20, 1623–1634, doi:10.3762/bjoc.20.145
- N115, in the same experimental conditions. The Nafion-doped membrane with compound TP2 with a 1.0 wt % loading showed the highest proton conductivity with 84 mS·cm−1. Keywords: electrolyser; fuel cells; Nafion-modified membranes; phosphonates; proton exchange membranes; triazine; Introduction
- membranes to ensure a high proton conduction or leading to an efficient reaction production of hydrogen and oxygen gases, with no risk of electrolyte leakage and restricted gas-crossover [15][16][17]. Also, besides their conductivity and their low permeability to fuel and oxidant, the chemical and
- observed in the spectra of new membranes compared to commercial Nafion [64]. Other characteristic bands of S–O group, CF2–CF and C–O–C are observed at near 1050, 980 and 960 cm−1, respectively, in the FTIR spectra [63]. The proton conductivity of the new proton exchange membrane is a key property relevant
Benzylic C(sp3)–H fluorination
Beilstein J. Org. Chem. 2024, 20, 1527–1547, doi:10.3762/bjoc.20.137
- preliminary electrochemical examples [93][101]. Middleton and co-workers described an alternating polarity approach for the fluorination of simple toluene derivatives in neat pyridine·HF (Figure 42) [102][103]. Poor conductivity necessitated the use of this waveform type. The benzylic fluorination was
Synthesis and physical properties of tunable aryl alkyl ionic liquids based on 1-aryl-4,5-dimethylimidazolium cations
Beilstein J. Org. Chem. 2024, 20, 1278–1285, doi:10.3762/bjoc.20.110
- -donating substituents in different positions of the phenyl ring and the bis(trifluoromethylsulfonyl)imide (NTf2) anion. We investigated the effect of additional methyl groups in the backbone of the imidazolium core on the physical properties regarding viscosity, conductivity and electrochemical window
- . With an electrochemical window of up to 6.3 V, which is unprecedented for TAAILs with an NTf2 anion, this new class of TAAILs demonstrates the opportunities that arise from modifications in the backbone of the imidazolium cation. Keywords: conductivity; electrochemical window; ionic liquids; tunable
- investigate the impact on the properties of ILs. The negative impact on viscosity and conductivity due to the higher mass should be comparatively low. We investigated different substituents with electron-donating as well as electron-withdrawing properties at the aryl ring and the difference between the ortho
Organic electron transport materials
Beilstein J. Org. Chem. 2024, 20, 672–674, doi:10.3762/bjoc.20.60
- general, this restriction also applies to n-dopants, compounds that reduce electron transport materials, which are important for increasing the electrical conductivity of n-type materials. However, there have been elegant solutions developed to counteract this, where air-stable dimers can be used which
- of the dopant [11] and therefore improved electrical conductivity. The overlap of desired characteristics for materials used in OECTs and organic thermoelectrics shows that there is a lot to be gained from the design of new electron transport materials. Whilst there are challenges still to be
Possible bi-stable structures of pyrenebutanoic acid-linked protein molecules adsorbed on graphene: theoretical study
Beilstein J. Org. Chem. 2024, 20, 570–577, doi:10.3762/bjoc.20.49
- modelled in single-layer graphene or in multilayer graphene. Graphene has been considered as an ideal material for the platform of biosensors [13][14][15][16][17][18][19][20][21][22][23], benefiting from its excellent properties such as large detection area and high thermal conductivity [14][24][25
- reflected light of the probe light. For such laser-based biosensors, graphene's conductivity can provide a unique advantage. In fact, the conductivity of multilayered graphene is highly anisotropic. Therefore, the use of multilayer graphene avoids the burning of biomaterials by lasers irradiated from the
Optimizing reaction conditions for the light-driven hydrogen evolution in a loop photoreactor
Beilstein J. Org. Chem. 2024, 20, 74–91, doi:10.3762/bjoc.20.9
- substrate and allowed to dry at room temperature. To improve the conductivity and achieve higher resolution SEM imaging, a 20 nm thick layer of Au was sputtered onto the sample surface. For EDS mapping, the samples were not sputtered with Au to avoid interference during the determination of Pt. UV–vis
Preparing a liquid crystalline dispersion of carbon nanotubes with high aspect ratio
Beilstein J. Org. Chem. 2024, 20, 52–58, doi:10.3762/bjoc.20.7
- . Keywords: aqueous dispersion; bar-coating; carbon nanotube; coffee-ring effect; liquid crystal; Introduction Carbon nanotubes (CNTs) are cylindrical carbon structures with high electrical conductivity and tensile strength in the direction of the tube, anticipated as durable and highly conductive fibers
- . However, the properties of produced fibers are often inferior to the inherent properties of CNTs. For instance, the wet-spinning method has resulted in CNT fibers with electrical conductivity up to 109,000 S/cm [1], which is about 1/4 that of Al, while individual single-walled CNTs (SWCNTs) have been
- estimated to have a conductivity of 900,000 S/cm [2]. The electrical conductivity of CNT fibers is primarily determined by the density of the fibers and the length of their constituent CNTs [3][4]. Therefore, enhancing CNT alignment is crucial for producing CNT fibers to endow inherent CNT properties, as
1-Butyl-3-methylimidazolium tetrafluoroborate as suitable solvent for BF3: the case of alkyne hydration. Chemistry vs electrochemistry
Beilstein J. Org. Chem. 2023, 19, 1966–1981, doi:10.3762/bjoc.19.147
- pollutants. This also facilitates their recovery and recycling. Furthermore, they generally exhibit low flammability, high thermal and chemical stability, good thermal and electrical conductivity, together with the ability to solubilize organic and inorganic compounds of different polarity [78][79][80][81
Anion–π catalysis on carbon allotropes
Beilstein J. Org. Chem. 2023, 19, 1881–1894, doi:10.3762/bjoc.19.140
- conductivity of the reactor was much lower [44]. This meant that already small currents produce high voltage. Despite this undesirable situation, conversion of 68 was observed to increase with increasing voltage. This observation was particularly intriguing because electric-field-induced anion–π catalysis on
A series of perylene diimide cathode interlayer materials for green solvent processing in conventional organic photovoltaics
Beilstein J. Org. Chem. 2023, 19, 1620–1629, doi:10.3762/bjoc.19.119
- transport, exhibit high thermal stability, are highly tunable in terms of their physical and chemical properties, and can be readily doped thereby increasing electronic conductivity. Some of the most widely used PDI materials for CILs are PDIN [14], PDINN [15], and PDINO (Figure 1a) [14][15]. Past work in
Synthesis, structure, and properties of switchable cross-conjugated 1,4-diaryl-1,3-butadiynes based on 1,8-bis(dimethylamino)naphthalene
Beilstein J. Org. Chem. 2023, 19, 674–686, doi:10.3762/bjoc.19.49
- theoretical and experimental studies revealed that the side groups of 1,4-diaryl-1,3-butadiynes have a significant impact on their useful characteristics [7][8][9][10][11][12][13][14]. For example, single-molecule conductivity, nonlinear optical properties, and the ability to serve as photosensitizers of
Microelectrode arrays, electrosynthesis, and the optimization of signaling on an inert, stable surface
Beilstein J. Org. Chem. 2022, 18, 1488–1498, doi:10.3762/bjoc.18.156
- never leaves the surface. The surface does not recover its original conductivity and the experiment shows a binding constant that is greater than either of the individual interactions. Alternatively, the surface-bound substrate could lead to avidity events where more than one of the ligands binds to the
First example of organocatalysis by cathodic N-heterocyclic carbene generation and accumulation using a divided electrochemical flow cell
Beilstein J. Org. Chem. 2022, 18, 979–990, doi:10.3762/bjoc.18.98
- recycle them, good stability, low flammability, good solubility ability for many molecules, salts and gases, the possibility to use them as reagents and/or solvents, large electrochemical window, good electrical conductivity, their ionic nature sometimes increases the reactivity and the selectivity of
- the electrodes so that lower concentrations of supporting electrolytes are needed to provide sufficient conductivity [28]. Applications of flow electrochemistry reported in the literature are mainly devoted to anodic oxidations, carried out in undivided cells, in which the counter electrode reaction
Post-synthesis from Lewis acid–base interaction: an alternative way to generate light and harvest triplet excitons
Beilstein J. Org. Chem. 2022, 18, 825–836, doi:10.3762/bjoc.18.83
- emitters can be realized by adding a Lewis acid to a fluorescent conjugated compound [15][16]. Lewis acids are common complexing agents [17] and are frequently used to dope conjugated polymers to enhance their conductivity while the luminescence is completely quenched [18][19]. In contrast, in the presence
- red-shifted with increasing the concentration of the Lewis acid, changing from 440 nm to 520 nm. In order to further explore the doping mechanism of Lewis acid on organic semiconductors, Yurash et al. found that B(C6F5)3 possessed the best doping effect and thus increased the conductivity, compared
Mechanistic studies of the solvolysis of alkanesulfonyl and arenesulfonyl halides
Beilstein J. Org. Chem. 2022, 18, 120–132, doi:10.3762/bjoc.18.13
- the removal of (as chloride ion), a chlorine attached to a carbon. Robertson and co-workers devised a system for a very accurate determination of rates of reaction by following changes in conductivity, with very precise temperature control. In this way, it was possible to observe systematic deviations
- obtaining the specific rates of solvolysis. When a strong acid is produced, as in Equation 7, conductivity measurements are usually the method of choice [31][77][78]. While very accurate measurements have been made, the ratios kH2O/kD2O and kMeOH/kMeOD have not proved to be very useful in assigning a
Synthesis and investigation on optical and electrochemical properties of 2,4-diaryl-9-chloro-5,6,7,8-tetrahydroacridines
Beilstein J. Org. Chem. 2021, 17, 2450–2461, doi:10.3762/bjoc.17.162
- giving an energy gap of 4.02 eV. The HOMO energy of derivative 4b was the highest and as a result it exhibited the lowest value of Egap and its electron conductivity was the best. The molecular electrostatic potential maps for tetrahydroacridines 4a–d are shown in Figure 10. The red and blue colors
Chemical syntheses and salient features of azulene-containing homo- and copolymers
Beilstein J. Org. Chem. 2021, 17, 2164–2185, doi:10.3762/bjoc.17.139
- peak around 690 nm supporting the oligomeric nature of the soluble fraction. The thermogravimetric analysis (TG) showed that PAZ-I2 was thermally more stable than PAZ-Br2. The electrical conductivity of PAZ-Br2 (5 × 10−3 S/cm) was far too superior compared to PAZ-I2 (10−6 S/cm). In 1997, Kihara
- polyazulene 3 or 3’ was soluble in various organic solvents such as toluene, dichloromethane, tetrahydrofuran (THF), and N,N’-dimethylformamide (DMF). The ‘true polyazulene’ exhibited the conductivity of 5.38 × 10−8 S/cm, which was increased to 8.16 × 10−3 S/cm upon exposure to iodine atmosphere, presumably
- acids on the polymer backbone. The direct current (DC) conductivity of protonated and iodine-doped 1,3-polyazulene 5 (0.74 and 1.22 S/cm respectively) was significantly higher than its neutral form (<10−11 S/cm). The increased conductivity of 1,3-polyazulene 5 upon protonation can be attributed to the
Constrained thermoresponsive polymers – new insights into fundamentals and applications
Beilstein J. Org. Chem. 2021, 17, 2123–2163, doi:10.3762/bjoc.17.138
- their physicochemical properties (e.g., solubility, viscosity) and can respond to stimuli in several ways by altering light transmitting abilities, shape, color, conductivity, as well as wettability [27][28]. Therefore, such functional polymers have a huge potential in numerous areas of application
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