Propylene carbonate/tetrabutylammonium

PC propylene carbonate NMO 3-methyl-2-oxazolidinone TBAI tetrabutylammonium iodide AN acetonitrile PN propionitrile GN glutaronitrile MAN methoxyacetonitrile MPN 3-methoxypropionitrile TBP tert-butylpyridine HMIml l-hexyl-3-methylimidazolium iodide DMPIml 1,2- dimethyl-3-propy-limidazolium iodide SOC Sumitomo Osaka Cement Co. Ltd. 

DMF = dimethylfonnamide DMSO = dimethyl sulfoxide PC = propylene carbonate, THE = tetrahydrofuran. HFP= 1.1,1,3,3,3-hexafluoro-2-propanol THAB = tetrahexylammonium benzoate TBAPFf, = tetrabutylammonium hexa-fluorophosphate. 

DMF = dimethylformamide NMP = A-methylpyrrolidone HMPA = hexamethylphosphotriamide DMSO = dimethyl sulfoxide sulfolane = tetramethylene sulfone PC = propylene carbonate THF = tetrahydrofuran, HFP = hexafluoro-2-propanol TBAP, TBAI = tetrabutylammonium perchlorate or iodide, respectively TEAP, TEAB = tetraethylammomum perchlorate or bromide, respectively TBAPFg = tetrabutylammonium hexafluorophosphate. 

Oxidation of trisubstituted N, N, IV -1 r i p h on y I -1,3,5 - tr i am i n o ben zcn cs (2a-2e) showed one to three irreversible cyclic voltammetric peaks. Potentials of the first peak fulfill the Hammett equation (against the 3 cr+ values, according to the additivity rule for three para-substituents) giving the slopes, i.e. the reaction constants p+, equal to —1.53, —1.45 and — 1.43 V/(3a+ unit) in solutions of methylene chloride, ACN and propylene carbonate, respectively (solutions contained 0.1 M tetrabutylammonium perchlorate)15. An interpretation of the above reaction constants is rather difficult because of the irreversibility (radical cations formed by the first electron transfer evidently disappear in fast chemical steps). However, relatively small values of p+ may be related15 to a charge delocalization onto the outer aromatic ring of the radical cation. 

Doping with these Group VA fluorides can be carried out electrochemically, using the polymer as the anode in a cell containing a solution of the dopant ion, e.g. tetrabutylammonium hexafluoroantimonate in propylene carbonate, or from the vapour phase. In the latter case the oxidative doping of polyacetylene is supposed to involve the following reaction of the dopant (for the case of AsFs) ... 

Experiments were conducted on trilayer PPy actuators to validate the effectiveness of the redox level-dependent admittance model. The electrolyte used was tetrabutylammonium hexafluorophosphate (TBA+PFg) in the solvent propylene carbonate (PC). The samples were predoped with PFg during fabrication, and the nominal concentration Co in the absence of DC bias was estimated to be fOOO mol/m based on the deposition conditions. In experiments different values of Cq were achieved by applying appropriate DC biases. Sinusoidal voltages of amplitude 0.05 V and frequency 0.08 — 200 Hz were superimposed on the DC voltage, as perturbations, for the measurement of admittance (or equivalently, impedance) spectra. 

Electrochemical characterization of monomer by cyclic voltammetry in solvents that will be used for electropolymerization. The solvents chosen for this purpose are usually acetonitrile, nitrobenzene, and propylene carbonate with about 0.1 M salt such as tetrabutylammonium hexafuorophosphate. Alternatively, if pyrrole or aniline derivatives will be studied, aqueous solutions can often be used. 

Polyselenophene (Fig. 16c) has been prepared. However, due to the difficulty in obtaining the monomer, the polymer has not been extensively investigated. Polymers of selenophene prepared electrochemically under appropriate conditions yield films with maximum conductivities of 10"- S cm [330,331]. Samples of p-doped selenophene produced chemically have conductivities on the same order of magnitude [332]. Applying 3-10 V between two electrodes in an electrolyte of 0.1 to 1 M lithium tetrafluoroborate or lithium perchlorate dissolved in benzonitrile or propylene carbonate gives polyselenophene films, as does the combination of tetrabutylammonium tetrafluoroborate in benzonitrile. However, other salts such as lithium hexafluoroarsenate, lithium hexafluorophosphate, tetrabutylammonium perchlorate, or silver perchlorate in combination with solvents such as acetonitrile or nitrobenzene were reported to produce either powders or no products at all [330,331,333]. 

Ion Mobilities, Fig. 2 Walden product (A rj) as function of temperature and solvent composition. Butyl triisoamylammonium tetraphenylborate in ethanol ( ), 1-propanol ( ), and acetonitrile ( ). Tetrabutylammonium perchlorate in 1-propanol (T) and acetonitrile (A). LiBr (O) in acetonitrile-propylene carbonate mixtures at temperatures from 25 °C to 75 °C... 

Created electrolyte comprised of solvent and ionic species. Possible ionic species include lithium tetrafluoroborate, tetrabutylammonium perchlorate, and tetraethylammonium tetrafluoroborate. Salt most preferred is ethyltriethylammonium tetrafluoroborate preferred solvent is non-aqueous. Examples include ethylene carbonate, propylene carbonate, N-methypyrrolidione, 1,2-dimethoxyethane, methyl formate, sulfuryl chloride, and tributyl phosphate. The most preferable solvent is a nitrile, specifically propionitrile. AIM solution of MTEATFB in propionitrile yielded conductivity of 48 mS/cm at 95°C and 28 mS/cm at 23°C. 

Notes TBA tetrabutylammonium PFe hexafluorophosphate PC propylene carbonate DBS dodecyl benzene sulfonate TFSI bis(trifluoromethylsulfonyl)imlde. 

This ligand class was thoroughly investigated by Jager in the 1980s and can be easily synthesised from the commercially available diethyl ethoxy-methylenemalonate and a suitable diamino spacer. The aluminium complex obtained via reaction with diethyl aluminium chloride efficiently catalyses the formation of propylene carbonate at 80 °C and 50 bar carbon dioxide (0.2 mol% catalyst). From the three ammonium salts tested as cocatalysts, tetrabutylammonium bromide again gave the best results (propylene carbonate yield 94%) followed by the tetrabutylammonium iodide (91%) and chloride (85%). 

Carbon dioxide is one of the most abundant carbon resources on earth. It reacts with an epoxide to give either a cyclic carbonate or a polycarbonate depending on the substrates and reaction conditions. Kinetic resolution of racemic propylene oxide is reported in the formation of both cyclic carbonate and polycarbonate. The fe ei value defined as ln[l-(conversion)(l+%ee)]/ln[l-(conversion)(l% ee)] reached 6.4 or 5.6 by using a Co(OTs)-salen complex with tetrabutylammonium chloride under neat propylene oxide or using a combination of a Co-salen complex and a chiral DMAP derivative in dichloromethane, respectively. 

Co(OAr)-salen complex [Ar = 2,4-(N02)2CeH3] with tetrabutylammonium chloride under neat propylene oxide, quite similar to the conditions for the cyclic carbonate synthesis, give polycarbonate with fe ei of 3.5. ° Without any additives, the use of Co(OAc)-salen provides the polycaronate with fe ei of 2.8. ... 

Aluminium monophenoxides substituted with a bullgr CMeaPh group or two t-butyl groups at the phenol and no ehlorine at the benzotriazole fragment displayed, when tested with propylene oxide and tetrabutylammonium bromide as coeatalyst, a signifieantly lower eatalytie aetivity than the chlorine substituted eatalyst (respeetively, 21%, 72% and 85% yields using 0.1 mol% catalyst, 1 mol% cocatalyst, 50 °C, 1 bar carbon dioxide). 

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