Tetrabutylammonium perchlorate

TETRABUTYLAMMONIUM PERCHLORATE AND BIS(4,4, 5,5 -TETRAMETHYL-2,2 -BI-l,3-DISELENOLYLIDENE) RADICAL ION (1 + ) PERCHLORATE 

Submitted by DENNIS A. STEPHENS, ANN E. REHAN, STEVE J. COMPTON, ROBERT A. BARKHAU, and JACK M. WILLIAMSf Checked by MARSHA M. LEE f  

Initially, 5 mL (34.9 mmol) of 70% perchloric acid is added dropwise, with stirring, to a solution of 9.91 g (29.2 mmol) of tetrabutylammonium hydrogen sulfate [Fluka] in 120 mL of distilled water. A white precipitate, [CH3(CH2)3]4N[C104], forms immediately. The solution is allowed to stir for 5 min and is then cooled at 0° for 40 min and filtered. The solid is washed with distilled water until the pH of wash is 7 and is dried under vacuum. The mother liquor is concentrated under vacuum (25°) to give additional product. The. products are combined and recrystallized three times from ethyl acetate the resulting solid is washed each time with distilled water. The crystals are dried in a vacuum desiccator. This yields 7.95 g (79.7%) of white crystals of tetrabutylammonium perchlorate (mp 208-210°). 

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Method A Tetrabutylammonium perchlorate (8.5 g, 25 mmol) was added to a solution containing DMF (49.5 mL) and hydrazine hydrate (0.5 tnL). To this solution was added green Pc2Lu (50 mg, 4.1 x 10 2 mmol). This mixture was stirred for 4 h. The blue-green of the starting solution rapidly became dark blue. Filtration and rapid evaporation under vacuum yielded 7 as a microcrystalline powder. 

TBAP, tetrabutylammonium perchlorate TEAB, tetraethylammonium bromide TBAI, tetrabutylammonium iodide. 

Electrolytic oxidation of acetonitrile solutions of monomer mixtures of dithioenopyrrole 23 and dithienothiophene 15a using tetrabutylammonium perchlorate as an electrolyte can produce poly(dithienopyrrole-dithienothiophene) copolymer which shows good electrochromic <1994EAC2159> characteristics. Similarly, films of poly(dithienopyrrole-thionapthene indole) and poly(dithienopyrrole-thionapthene indole) co-polymers can be obtained from DTT and DTP with thionapthene indole 85 (TNI) <1996SM(82)11>. 

In 1986, Breikss and Abruna reported electrochemical and mechanistic studies on a close analogue of the rhenium complex, (Dmbpy)Re[CO]3Cl, where Dmbpy = 4,4 dimethyl 2,2 bipyridine. The cyclic voltammogram of the complex at platinum in CH3CN/tetrabutylammonium perchlorate is shown in Figure 3.56 for simplicity we will consider only the electrochemistry taking place above c. —2.3V vs. SCE. 

A combination of HPLC and amperometric detection was proposed for determination of tributylstannyl oxide in antifouling paint. The detector is of the static hanging Hg drop type in a flow cell, the solvent is CH2CI2/THF, containing tetrabutylammonium perchlorate as supporting electrolyte. The oxidation mechanism depicted in reactions 4... 

Electrochemical oxidation of epoxides in absence of nucleophiles, catalyses a rearrangement to the carbonyl compound. The electrolyte for this process is dichlo-romethane with tetrabutylammonium perchlorate. Reaction, illustrated in Scheme 8.7, involves the initial formation of a radical-cation, then rearrangement to the ketone radical-cation, which oxidises a molecule of the substrate epoxide. The process is catalytic and requires only a small charge of electricity [73]. 

I. 4-methoxyacetophenone (30 //moles) was added as an internal standard. The reaction was stopped after 2 hours by partitioning the mixture between methylene chloride and saturated sodium bicarbonate solution. The aqueous layer was twice extracted with methylene chloride and the extracts combined. The products were analyzed by GC after acetylation with excess 1 1 acetic anhydride/pyridine for 24 hours at room temperature. The oxidations of anisyl alcohol, in the presence of veratryl alcohol or 1,4-dimethoxybenzene, were performed as indicated in Table III and IV in 6 ml of phosphate buffer (pH 3.0). Other conditions were the same as for the oxidation of veratryl alcohol described above. TDCSPPFeCl remaining after the reaction was estimated from its Soret band absorption before and after the reaction. For the decolorization of Poly B-411 (IV) by TDCSPPFeCl and mCPBA, 25 //moles of mCPBA were added to 25 ml 0.05% Poly B-411 containing 0.01 //moles TDCSPPFeCl, 25 //moles of manganese sulfate and 1.5 mmoles of lactic acid buffered at pH 4.5. The decolorization of Poly B-411 was followed by the decrease in absorption at 596 nm. For the electrochemical decolorization of Poly B-411 in the presence of veratryl alcohol, a two-compartment cell was used. A glassy carbon plate was used as the anode, a platinum plate as the auxiliary electrode, and a silver wire as the reference electrode. The potential was controlled at 0.900 V. Poly B-411 (50 ml, 0.005%) in pH 3 buffer was added to the anode compartment and pH 3 buffer was added to the cathode compartment to the same level. The decolorization of Poly B-411 was followed by the change in absorbance at 596 nm and the simultaneous oxidation of veratryl alcohol was followed at 310 nm. The same electrochemical apparatus was used for the decolorization of Poly B-411 adsorbed onto filter paper. Tetrabutylammonium perchlorate (TBAP) was used as supporting electrolyte when methylene chloride was the solvent. 

Poly B-411, a water-soluble, blue dye (IV) has been used as a lignin model by Glenn et al. (18). The dye was deposited onto a piece of filter paper, which was then attached directly to a glassy carbon anode. The anolyte contained 10 mM veratryl alcohol and 0.1 M tetrabutylammonium perchlorate (TBAP) in methylene chloride. The catholyte contained only... 

The step 1 product and 2,2, 5,2"-terthiophene were reacted to form the copolymer using cyclic voltammetry and electro-copolymerizalion. Cyclic voltammetry in CH2CI2 containing 0.1 M tetrabutylammonium perchlorate supporting electrolyte indicated that the co-monomer oxidation began at approximately 0.70 V vs. Ag/Ag+. 

The exhaustive controlled-potential reduction of 6-chioro-l-phenylhex-l-yne at — 1.57 V in dimethylformamide containing tetrabutylammonium perchlorate gave a mixture of products. among which was ( >(2-phcnylvinyl)cyclobutane (9).11 It is probable that the mechanism involves initial isomerization of the acetylene to an allene 8 which is reduced at — 1.57 V to the radical anion. Protonation and further onc-clectron reduction then yield the allylic anion. An intramolecular nucleophilic substitution eventually gives the cyclobutane.11... 

FIGURE 3. Cyclic voltammetric curves for the tetracobaltcarbonyl cluster in thf containing 0.1 M tetrabutylammonium perchlorate. Sweep rate, 200 mVs-1. The inset shows the scans of the first (0/—1) redox couple at 1000,500,200 and 100mVs-1. Reprinted with permission from Reference 27. Copyright 1986, American Chemical Society... 

FIGURE 5. Cyclic voltammogram of l,4-bis(triphenyl-phosphonio)benzodiiodide in dmf containing 0.1 M tetrabutylammonium perchlorate. The abscissa is with reference to SCE. Reproduced by permission of VCH from Reference 42... 

Our second study was to accomplish substantially electroinitiated anionic polymerization. In order to demonstrate this, polarographic studies should be carried out in the same medium as the polymerizatia-tion. Actually half-wave potentials of several monomers were measured in dimethoxyethane with tetrabutylammonium perchlorate. The potentials... 

A low molecular weight of polytetrahydrofuran was accidentally found in an anodic solution, when an electric current was passed through a solution of styrene with tetrabutylammonium perchlorate in tetra-hydrofuran (23), At the cathode styrene was polymerized and no copolymers were observed in either solution. A possible explanation of the initiation of polymerization can be offerend to account for the preliminary experimental results obtained. It may have been caused by interaction of the perchlorate radical formed at the anode [Eq. (11)] with tetrahydrofuran, providing an axonium ion. 

Another example has been found in the author s laboratory. In the course of studies on the synthesis of metal-olefin complexes by means of cathodic reduction in dry organic mediums, a variety of linear oligomers were prepared on the nickel atom formed at the platinum cathode in electrolytic solution (32). The solution contained tetracispyridine nickel perchlorate or nickel dichloride and butadiene in ethanol or dimethoxye-thane, using tetrabutylammonium perchlorate as an electrolyte. 

Figure 12.7 Cyclic voltammograms for the oxidation of 10 mM TCNQ in acetonitrile at a 12.4-pim-radius Pt disk electrode. Concentration of the supporting electrolyte, tetrabutylammonium perchlorate (A) 100 mM (B) 1 mM (C) 0 mM. The solutions were purged with N2. [From Ref. 75, reproduced with permission of the copyright holder.]...

Polarographic data for pseudoazulenes 26, 27, 39, and 40 have been reported.51 Reduction of azalenes 26 and 39 at a dropping mercury electrode using tetrabutylammonium perchlorate as the carrier electrolyte in acetoni-... 

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