Toluene electrochemical reduction

Reduction of fullerenes to fullerides — Reversible electrochemical reduction of Ceo in anhydrous dimethylformamide/toluene mixtures at low temperatures leads to the air-sensitive coloured anions Qo" , ( = 1-6). The successive mid-point reduction potentials, 1/2, at -60°C are -0.82, -1.26, -1.82, -2.33, —2.89 and —3.34 V, respectively. Liquid NH3 solutions can also be used. " Ceo is thus a very strong oxidizing agent, its first reduction potential being at least 1 V more positive than those of polycyclic aromatic hydrocarbons. C70 can also be reversibly reduced and various ions up to... 

UV photolysis of CpMn(CO)3 in toluene leads to loss of CO and formation of CpMn(CO)2( ] -toluene). Kinetic studies suggest that the binding energy of the toluene is ca. 60kJmor. The binding of H2 to CpMn(CO)2 has been studied in supercritical CO2 solvent. It has been proposed that pyrylium and pyridinium salts such as (35) can be used to label proteins and thereby aid in the detection and characterization of receptor sites. Cymantrene bound to lysine residues of bovine serum albumin (BSA) has been used as a redox label. Electrochemical reduction of the label established an impressive BSA detection limit of 2 x 10 M. 

Fullerenes have high electron affinity so that electrochemical reduction processes are easily observed. The solution-phase electrochemical response of Cgg and C70 fullerenes in MeCN/toluene mixtures at low temperature consisted of six reversible one-electron reductions at potentials between -0.97 to -3.26 V vs. Fc7Fc+ (Xie et al., 1992). This can be represented as successive one-electron transfer processes ... 

Raman, IR, and near-IR spectroscopy and TGA analyses of the functionalized SWNTs confirmed the attachment of radical groups. Aryl diazonium salts have been used to generate radicals for addition to SWNTs using electrochemical reduction.Up to 49wt% aryl functionality has been achieved and a stable homogeneous solution of aryl functionalized SWNT (50 mg L ) up to 36 h in chloroform is obtained after a 30 min sonication. Polymeric radical addition to SWNTs has been shown to occur during in situ free radical polymerization of styrene in toluene and sodium 4-styrenesulfonate in water. 

Methyl trichloroacetate reacts with olefins in the presence of transition-metal catalysts to give mixtures of the corresponding butyrate and y-butyrol-actone. Substituted y-butyrolactones are produced in the radiation-induced addition of alcohols or the electrochemical reductive addition of acetone to a/3-unsaturated esters. Acetylenic Grignard reagents react with y-lactones to give products of double addition, whereas the analogous lithium salts react only once. The products observed in the pyrolysis of y-lactone toluene-/ -sulphonylhydrazone sodium salts can be accounted for by the intermediacy of an oxycarbene. ... 

Electrochemical redox studies of electroactive species solubilized in the water core of reverse microemulsions of water, toluene, cosurfactant, and AOT [28,29] have illustrated a percolation phenomenon in faradaic electron transfer. This phenomenon was observed when the cosurfactant used was acrylamide or other primary amide [28,30]. The oxidation or reduction chemistry appeared to switch on when cosurfactant chemical potential was raised above a certain threshold value. This switching phenomenon was later confirmed to coincide with percolation in electrical conductivity [31], as suggested by earlier work from the group of Francoise Candau [32]. The explanations for this amide-cosurfactant-induced percolation center around increases in interfacial flexibility [32] and increased disorder in surfactant chain packing [33]. These increases in flexibility and disorder appear to lead to increased interdroplet attraction, coalescence, and cluster formation. 

A further adaptation of the titaniuni(m) reduction uses di(cyclopentadienyl)-titanium ions as mediator. The mediator is generated in aqueous acid and reacted outside the electrochemical cell with a solution of the nitrobenzene in toluene. The... 

The product of the electrochemical reaction was extracted with cyclohexane. The yields observed in the reactions of PhBr and PhCH2Br were 35 and 75%, respectively. In the reaction of PhCH2Br, no toluene was formed, indicating that the process was highly selective and that the reduction of the halogenated substrate was avoided. It was further verified that, at the end of the electrolysis, the catalytic system completely regained its reversibility. The nickel(II) catalyst remained totally in the ionic liquid after the extraction of products, and the catalyst system was reusable. 

Fullerene is an ideal candidate as a component of molecular batteries because it shows six chemically and electrochemically reversible, one-electron reduction70 and one oxidation process.71 In particular, the first reduction process occurs at easy accessible potentials (—0.98 V versus Fc +/Fc in MeCN/toluene solution at 263 K)70 and it is thus the most suitable process to exploit in charge storing devices. To covalently append fullerene to the dendritic structure, chemical functionalization of the bucky-ball is necessary. Fortunately, most of its derivatives keep the reversible electrochemical properties of Ceo, at least for the first reduction process, which usually occurs at more negative potentials than that of fullerene. 

Some work has been done on the reduction of the alpha and epsilon dinitrotoluenes by electrochemical means. Brand and Loller (13) have prepared from the epsilon compound a 2-2-dinitrO 6-6-azoxytoluene and a 2-2-dinitro-3-hydrox -6-6-azotoluene. The formation is determined by the solution used. The alpha dinitro-toluene gives similar substances. 

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