Cyclic phosphonium ionic liquids

• Sharon I. Lall-Ramnarine,
• Joshua A. Mukhlall,
• James F. Wishart,
• Robert R. Engel,
• Alicia R. Romeo,
• Masao Gohdo,
• Sharon Ramati,
• Marc Berman and
• Sophia N. Suarez

Beilstein J. Org. Chem. 2014, 10, 271–275, doi:10.3762/bjoc.10.22

• phosphonium salts increase with increasing ring size for two of the compounds synthesized. As suggested by the viscosity results, the conductivities of the phosphonium ILs are lower than those for their ammonium congeners, and that for both families they decrease with increasing ring size. The conductivity of

Crystal design using multipolar electrostatic interactions: A concept study for organic electronics

• Peer Kirsch,
• Qiong Tong and
• Harald Untenecker

Beilstein J. Org. Chem. 2013, 9, 2367–2373, doi:10.3762/bjoc.9.272

• and H∙∙∙O contacts. The calculation of transfer integrals based on the crystal structure indicates that in spite of the brickwall-structure, due to a slight asymmetry of the “layering”, the hole conductivity is rather anisotropic (1D), whereas the electron conductivity is three-dimensional (3D

Flow synthesis of phenylserine using threonine aldolase immobilized on Eupergit support

• Jagdish D. Tibhe,
• Hui Fu,
• Timothy Noël,
• Qi Wang,
• Jan Meuldijk and
• Volker Hessel

Beilstein J. Org. Chem. 2013, 9, 2168–2179, doi:10.3762/bjoc.9.254

• calculate the mass transfer coefficient, porosity (ε) = 0.5 estimated, density (ρ) = 1024 kg/m3, viscosity of fluid (μ) = 0.00134 kg/ms and thermal conductivity (K) = 0.58 (W/m·K). The Reynolds number (Re) for a fluid flow through a bed of approximately spherical particles of diameter D can be calculated

Molecular assembly of amino acid interlinked, topologically symmetric, π-complementary donor–acceptor–donor triads

• M. B. Avinash,
• K. V. Sandeepa and
• T. Govindaraju

Beilstein J. Org. Chem. 2013, 9, 1565–1571, doi:10.3762/bjoc.9.178

• organization of D-A stacks could bring about significant improvement in the conductivity through directional charge transfer. Herein, we have chosen three D-A-D triads (1–3) of pyrene and NDI interlinked by different amino acids, namely alanine, phenylalanine and isoleucine (Figure 1). The choice of amino

Simple and rapid hydrogenation of p-nitrophenol with aqueous formic acid in catalytic flow reactors

• Rahat Javaid,
• Shin-ichiro Kawasaki,
• Akira Suzuki and
• Toshishige M. Suzuki

Beilstein J. Org. Chem. 2013, 9, 1156–1163, doi:10.3762/bjoc.9.129

• recorded at room temperature by using a spectrophotometer (U–3310; Hitachi). The collected gaseous products were analyzed by using a gas chromatograph (GC–8A; Shimadzu Corp.) equipped with thermal conductivity detector (TCD). A molecular sieve (5 Å) column (3 mm × 6 m) was used for H2 with argon as the

High-spin intermediates of the photolysis of 2,4,6-triazido-3-chloro-5-fluoropyridine

• Sergei V. Chapyshev,
• Denis V. Korchagin,
• Patrik Neuhaus and
• Wolfram Sander

Beilstein J. Org. Chem. 2013, 9, 733–742, doi:10.3762/bjoc.9.83

• prepared by vacuum co-deposition of two separate molecular beams (Ar and triazide 11 vapor) on the tip of an oxygen-free high-conductivity copper rod (75 mm length, 3 mm diameter) cooled at 5 K. The vapor of 11 was produced by an oven heating the polycrystalline 11 to 60 °C. The matrix-isolated samples

Spin state switching in iron coordination compounds

• Philipp Gütlich,
• Ana B. Gaspar and
• Yann Garcia

Beilstein J. Org. Chem. 2013, 9, 342–391, doi:10.3762/bjoc.9.39

Molecular switches and cages

• Dirk Trauner

Beilstein J. Org. Chem. 2012, 8, 870–871, doi:10.3762/bjoc.8.97

• features include their absorption spectra, conductivity, geometry and bistability, as well as their polarity, solubility, efficacy, or catalytic activity. Photoswitches are covered extensively, ranging from diarylethenes (Pu, Wagenknecht) to dihydroazulenes/vinylheptafulvenes (Nielsen) and azobenzenes

Formation of carbohydrate-functionalised polystyrene and glass slides and their analysis by MALDI-TOF MS

• Martin J. Weissenborn,
• Johannes W. Wehner,
• Christopher J. Gray,
• Robert Šardzík,
• Claire E. Eyers,
• Thisbe K. Lindhorst and
• Sabine L. Flitsch

Beilstein J. Org. Chem. 2012, 8, 753–762, doi:10.3762/bjoc.8.86

• functionalisation, which has the potential for self-formation of a matrix (self-matrix) for MS analysis, at the same time as acting as a hydrophobic tether [11][12][13]. However, polystyrene has only minimal innate electrical conductivity and to our knowledge has never been used successfully, unmodified, as a

• dichloride hydrate [14]. The addition of electron-accepting additives, however, did not completely suppress the mass shifts observed during MALDI-TOF MS on low-conductivity supports. Additionally, glass slides coated with conductive material are expensive and limited in their utility [14]. In order to

• procedures. For the coupling a combination of HBTU/DIPEA or HATU/DIPEA in dry DMF was applied yielding 74% of 5 and 71% of 7. The analysis of molecules on materials such as polystyrene by MALDI-TOF MS is difficult and irreproducible, largely due to their minimal electrical conductivity. To our knowledge

Cyanoethylation of the glucans dextran and pullulan: Substitution pattern and formation of nanostructures and entrapment of magnetic nanoparticles

• Kathrin Fiege,
• Heinrich Lünsdorf,
• Sevil Atarijabarzadeh and
• Petra Mischnick

Beilstein J. Org. Chem. 2012, 8, 551–566, doi:10.3762/bjoc.8.63

• conductivity up to 2.4 × 10−3 S/cm. Thus, a lithium ion polymer battery with cyanoethylpullulan as a matrix polymer could be built with high charge/discharge efficiency [9]. Another example is a vertical electrochemical transistor based on poly(3-hexylthiophene), which was realized by making use of the film

Improved syntheses of high hole mobility phthalocyanines: A case of steric assistance in the cyclo-oligomerisation of phthalonitriles

• Daniel J. Tate,
• Rémi Anémian,
• Richard J. Bushby,
• Suwat Nanan,
• Stuart L. Warriner and
• and Benjamin J. Whitaker

Beilstein J. Org. Chem. 2012, 8, 120–128, doi:10.3762/bjoc.8.14

• conductivity (PR-TRMC) method because of the very high frequency employed in PR-TRMC. At such high frequencies the charge carriers only migrate over microdomains, avoiding deep traps. Furthermore PR-TRMC records the combined mobilities of the holes and the electrons. Hence, although there are a number of PR

Imidazole as a parent π-conjugated backbone in charge-transfer chromophores

• Jiří Kulhánek and
• Filip Bureš

Beilstein J. Org. Chem. 2012, 8, 25–49, doi:10.3762/bjoc.8.4

• with a practical application. For instance, in 2002 Yang et al. [114] reported a fairly simple organic-electrical bistable device (OBD) based on amine 83 (Figure 15). Yang’s OBD consisted of organic material based on 83 with a built-in thin aluminum active layer. The OBD’s conductivity in the two

Advances in synthetic approach to and antifungal activity of triazoles

• Kumari Shalini,
• Nitin Kumar,
• Sushma Drabu and
• Pramod Kumar Sharma

Beilstein J. Org. Chem. 2011, 7, 668–677, doi:10.3762/bjoc.7.79

• triazoles Triazoles have been suggested as water replacements in proton conductors used in fuel cells. Once doped into membranes, these triazoles improve the conductivity of the membranes under anhydrous conditions. Due to their amphoteric nature, these compounds act as proton acceptors and donors. Their

• conductivity in the order of 1 mS/cm in dry conditions at 100 °C for composites of 4,5-dicyano-1H-1,2,3-triazole with polyacrylonitrile in the absence of any other external proton sources [68]. Some triazole derivatives such as 4-amino-5-mercapto-3-methyl-1,2,4-triazole (AMMT), 4-amino-5-mercapto-3-ethyl-1,2,4

Miniemulsion polymerization as a versatile tool for the synthesis of functionalized polymers

• Daniel Crespy and
• Katharina Landfester

Beilstein J. Org. Chem. 2010, 6, 1132–1148, doi:10.3762/bjoc.6.130

• p-toluenesulfonic acid. The conductivity was increased dramatically when stannous chloride was employed, which the authors attributed to the reduction of part of pernigraniline in the emeraldine base structure. Such oxidative polymerization of aniline can be used to add an additional conductive

• pyrrole initiated by iron(III) chloride on polystyrene latexes produced in miniemulsion to yield particles with sizes ranging from 50 to 70 nm [96]. The conductivity of pellets prepared from the particles was found to be 15.4 S∙cm−1. Core–shell morphologies could be identified by selectively dissolving

Self-assembly and semiconductivity of an oligothiophene supergelator

• Pampa Pratihar,
• Suhrit Ghosh,
• Vladimir Stepanenko,
• Sameer Patwardhan,
• Ferdinand C. Grozema,
• Laurens D. A. Siebbeles and
• Frank Würthner

Beilstein J. Org. Chem. 2010, 6, 1070–1078, doi:10.3762/bjoc.6.122

• . The charge transport ability of such elongated fibres of quaterthiophene π-system was explored by the pulse radiolysis time resolved microwave conductivity (PR-TRMC) technique and moderate mobility values were obtained. Furthermore, initial AFM and UV-vis spectroscopic studies of a mixture of our

• mono- and bithiophene bisurea compunds [18]. Therefore, the charge transport properties of T1 in the solid state were investigated by pulse radiolysis time resolved microwave conductivity (PR-TRMC) measurements [27]. PR-TRMC measurements were performed with a solid (powder) sample of T1 using the same

• methodology as reported previously [27][28]. The sample (~32.5 mg) was irradiated with a short pulse of 3 MeV electrons, which lead to the formation of charges in the material during the pulse. The conductivity was measured as a function of time by microwave conductivity measurements. The dose-normalized PR

Molecular recognition of organic ammonium ions in solution using synthetic receptors

• Andreas Späth and
• Burkhard König

Beilstein J. Org. Chem. 2010, 6, No. 32, doi:10.3762/bjoc.6.32

Flow through reactors for organic chemistry: directly electrically heated tubular mini reactors as an enabling technology for organic synthesis

• Ulrich Kunz and
• Thomas Turek

Beilstein J. Org. Chem. 2009, 5, No. 70, doi:10.3762/bjoc.5.70

• pressure would lead to loss of reactant in an open system. Measurements at temperatures higher than 32 °C are not possible at all. The progress of the reaction can be measured easily online by determining the electrical conductivity of the reaction mixture leaving the reactor. Electrical conductivity is

• directly proportional to the formation of formic acid and thus proportional to conversion. As a measure for conversion the conductivity of the reaction mixture at the reactor outlet was used. The reaction follows first order kinetics (within the concentrations we have chosen), which facilitates the

• the activation energy and the pre-exponential factor. To some extent the values for k scatter. This could be based on the conductivity cell which was used for measuring the conversion as it had no temperature control. Measured values showed some influence on fluid temperature. From the Arrhenius plot

Coaxial electrospinning of liquid crystal-containing poly(vinylpyrrolidone) microfibres

• Eva Enz,
• Ute Baumeister and
• Jan Lagerwall

Beilstein J. Org. Chem. 2009, 5, No. 58, doi:10.3762/bjoc.5.58

• properties of the polymer solution, and operational conditions. The most important are: type of polymer and its concentration; viscosity, electrical conductivity, polarity and surface tension of the solvent; applied electric field, distance between spinneret and collector, flow rate of the polymer solution

A convenient method for preparing rigid-core ionic liquid crystals

• Julien Fouchet,
• Laurent Douce,
• Benoît Heinrich,
• Richard Welter and
• Alain Louati

Beilstein J. Org. Chem. 2009, 5, No. 51, doi:10.3762/bjoc.5.51

• liquids (ILs) have revealed their many useful properties such as extremely low volatility, high thermal stability, non-flammability, high chemical and radiochemical stability, high ionic conductivity and wide electrochemical window [1][2][3]. In addition, the ILs have been used as reaction media

• range of materials (Ionic liquid crystals, ILCs) with novel and tunable characteristics such as those of ordered and oriented hybrid compound semiconductors exhibiting both electronic and ionic conductivity [10]. For this, the imidazolium unit is an excellent platform that can be designed to promote