Electrosynthesis and electrolytic

Electrolysis offers an alternative route for organic synthesis via the formation of anion and cation radical intermediates. However, traditional electrolytic methods suffer from a number of limitations such as heterogeneity of the electric field, thermal loss due to heating and obligatory use of supporting electrolytes. These factors either hamper electrosynthetic efficiency or make the separation process cumbersome. The combination of electrosynthesis and microreaction technology effectively overcomes these difficulties. 

Electrochemical nanotechnologies using ultramicroelectrodes such as the tips of electrochemical scanning tunneling microscopes and related devices [446,447] are of special interest both, for conducting local electrosynthesis and for electrochemical modification. The tip nanotechnique in electrolyte solutions ensures the optimal level of surface purity, offers additional possibilities in governing the processes by varying the potentails of the tip electrode and the substrate, and may also be used for... 

Electrolytic decarboxylative coupling of sodium salts of carboxylic acids takes place during their electrolysis. Carbon dioxide is eliminated, and the free radicals thus generated couple to form hydrocarbons or their derivatives. The reaction is referred to as the Kolbe electrosynthesis and is exemplified by the synthesis of 1,8-difluorooctane from 5-fluorovaleric acid (equation 469) [574]. Yields of homologous halogenated acids range from 31% to 82% [574]. 

Surendranath Y, Dinca M, Nocera DG (2009) Electrolyte-dependent electrosynthesis and activity of cobalt-based water oxidation catalysts. J Am Chem Soc 131 2615-2620 Kanan MW, Yano J, Suiendranath Y, Dinca M, Yachandra VK, Nocoa DG (2010) Structure and Valency of a Cobalt-Phosphate Wattn Oxidation Catalyst Detmmined by in Situ X-ray Spectroscopy. J Am Chem Soc 132 13692-13701... 

The ohmic drop frequently represents an important fraction of the cell voltage and plays a major role in the heat generation terms. This is especially true in organic electrosynthesis where current densities are high and electrolyte conductivities low. A major concern in electrochemical engineering is clearly linked to the design of cells with minimum ohmic drops. 

Problems reviewed include the electrosynthesis of organometallic compounds and electrolytic oxidation of organic substances in fuel cells. Also considered are the possibilities of using electrochemical methods to investigate catalytic processes in solutions and electrochemical gentidiion of free radicals. 

Interest in using ionic liquid (IL) media as alternatives to traditional organic solvents in synthesis [1 ], in liquid/liquid separations from aqueous solutions [5-9], and as liquid electrolytes for electrochemical processes, including electrosynthesis, primarily focus on the unique combination of properties exhibited by ILs that differentiate them from molecular solvents. 

Aqueous electrolytes proposed in the literature for cathodic electrodeposition of lead selenide are generally composed of dissolved selenous anhydride and a lead salt, such as nitrate or acetate. Polycrystalline PbSe films have been prepared by conventional electrosynthesis from ordinary acidic solutions of this kind on polycrystalline Pt, Au, Ti, and Sn02/glass electrodes. The main problem with these applications was the PbSe dendritic growth. Better controlled deposition has been achieved by using EDTA in order to prevent PbSeOs precipitation, and also acetic acid to prevent lead salt hydrolysis. 

The electrosynthesized (0EP)Ge(CgHs)C10, was characterized in situ by thin-layer spectroelectrochemistry. The final product of electrosynthesis was spectrally compared with the same compounds which were synthesized using chemical and photochemical methods(35). (0EP)Ge(C6H5)Ci and (0EP)Ge(CsHs)0H were also electrochemically generated by the use of specific solvent/supporting electrolyte systems(35). 

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