Tetrabutylammonium tetrafluoroborate supporting electrolyte

Dibenzyl ditellurium was obtained in 70% yield by alkylation of the electrochemically generated ditelluride dianion with benzyl chloride in acetonitrile3. The ultrasonically promoted electrochemical reduction of tellurium powder was performed in H-type cells with the compartments separated by glass frits. Acetonitrile served as solvent and tetrabutylammonium tetrafluoroborate or hexafluorophosphate as the supporting electrolyte. At potentials beyond -1.1 V the dark-red ditelluride dianion is formed in the cathode and in the central compartment3. 

Tetrahexylammonium perchlorate and tetrabutylammonium tetrafluoroborate have been used as supporting electrolyte in benzene and chlorobenzene, respectively. The latter was suggested [418] to be an excellent solvent for the study of reversible oxidations and reductions of aromatic compounds. The TLV for chlorobenzene is 75 ppm. 

The general electrochemical procedure for the carbon dioxide incorporation was based on the use of one-compartment cells fitted with consumable anodes of magnesium or zinc [12]. Electrocarboxylations were carried out in DMF at constant current density, using tetrabutylammonium tetrafluoroborate (10 2 m) as supporting electrolyte. The catalyst was introduced in a 10% molar ratio with respect to the substrate and carbon dioxide was bubbled through the solution at atmospheric pressure. Electrolyses were generally run at room temperature and reactions were stopped when starting material was consumed or when the faradaic yield attained 30%. 

Fig. 10 Cyclic voltammetric (CV) reduction and oxidation scans of a terfluorene at 2.5 x 10 1 M in acetonitrile and toluene (1 1 v/v) with 0.1 M tetrabutylammonium tetrafluoroborate as the supporting electrolyte using a glassy carbon electrode...

Tetrabutylammonium tetrafluoroborate (BU4NBF4) is usually used as a supporting electrolyte, and dichloromethane (CH2CI2) is suitable as the solvent because of its low viscosity at low temperatures. Trifluorometha-nesulfonic acid (CF3SO3H or TfOH) is added in the cathodic chamber to facilitate the reduction of protons in the cathodic process. It should be noted that both an anodic process and a cathodic process take place simultaneously in electrochemical reactions, and both processes should proceed smoothly to promote the overall reaction. 

FIG. 7 Cyclic voltammogram of a self-assembled spherical gold microelectrode, (a) In a 7.5 mM aqueous solution of hexaamineruthenium(III) chloride and 1 M KC1 electrolyte. Electrode diameters, from top to bottom, 10, 5, 4, 3, 1.7 /rm. Scan rate 0.1 V/s. (b) In a 6.5 mM solution of tetracyanoquinodimethane in acetonitrile. Supporting electrolyte tetrabutylammonium tetrafluoroborate (0.1 M). Electrode diameter 6 /am. Scan rate 0.1 V/s. (Reprinted with permission from Ref. 20. Copyright 1997 American Chemical Society.)... 

The thiophene dimer and trimer have been electrochemically polymerized to grow poly thiophene films at lower potentials [248]. The dimer—2,2 -bithiophene—polymerizes at 1.2 V (versus SCE) to produce polythiophene with conductivities up to I S cm" [249]. The trimer— -terthiophene (2,2 5, 2"-terthienyl)—electrochemically polymerizes at 1.0 V (versus SCE) to yield films with conductivities up to 10" S cm" [201]. A mixture with sulfuric acid or use of tetrabutylammonium tetrafluoroborate as the supporting electrolyte in acetonitrile with the trimer produced no polymer, only gels or powder, respectively [250]. 

Polythiophene and its derivatives can be polymerized by chemical or electrochemical techniques. In this study, the electrochemical method was utilized.The mechanism is a cationic radical polymerization 11). The polymerization pathway can be summarized in the following steps 1) oxidation of the monomer to form a radical cation, 2) dimerization of the radical cations, 3) loss of proton to yield a neutral dimer, 4) oxidation of dimer to form a radical cation, 5) reaction of dimer radical cation with another radical cation, 6) repeat of the this study, are 3-methylthiophene, tetrabutylammonium tetrafluoroborate (TBATFB), as the supporting electrolyte. The organic solvent was acetonitrile. The resulting polymer was the first conducting polymer family found to be stable in air and water in both their doped or undoped state. 

Electrochemical conditions for the electropolymerization of 3-methylthiophene have been optimized. Responsive films for detection of anionic species in FIA were prepared under the following genei conditions 3-methylthiophene concentration (0.5 to 0.15 M), supporting electrolyte (tetrabutylammonium tetrafluoroborate) concentration (0.5 to 0.15 M), solvent (acetonitrile), applied potential (1.600 volts) and time of polymerization (30-60 seconds). 

Tetrabutylammonium tetrafluoroborate (0.1 M) as the supporting electrolyte, scan rate 100 mV s , 20 °C potential in mV, measured with a Pt disk working electrode in degassed dichloromethane solution. The values are referenced to the ferrocene/ferrocinium couple This value is attributable to the ether group as (R)-2,2 -dimethoxy-l,l -binaphthylene gave a value of 1,030 mV... 

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