Electrolysis paired

When a copper anode is used instead of platinum, the resulting chlorosilane is subsequently reduced to a Si—Si coupling product in a one-pot reaction (equation 49)57. Interestingly, when a mixture of hydrosilane and chlorosilane is electrolyzed using a copper anode and a platinum cathode, a Si—Si coupling product is obtained in 64% yield on the basis of the sum of both reagents used. Thus, the paired electrolysis of hydrosilane on the anode and chlorosilane on the cathode proceeds to give disilane (equation 50)57. 

Another alternative is the autoredox reaction. D-Gluconic acid and D-glucitol were obtained concurrently in 90% yield by paired electrolysis of glucose with a lead sheet cathode and a dimensionally stable anode in a press-filtration diaphragm cell.20... 

Hilt G (2003) Convergent paired electrolysis for the three-component synthesis of protected homoallylic alcohols. Angew Chem Int Ed 42 1720-1721... 

Ishifune M, Yamashita H, Matsuda M, Ishida H, Yamashita N, Kera Y, Kashimura S, Masuda H, Murase H (2001) Electro reduction of aliphatic esters using new paired electrolysis systems. Electrochim Acta 46 3259-3264... 

In a paired electrolysis, amines have been A -alkylated in alcoholic solution. At the Pt(Pt) anode the alcohol was oxidized to an aldehyde that condensed with the amine to an imine the imine was reduced at the cathode to a secondary amine. Benzylamine was thus electrolyzed to benzylethylamine in 96% yield (65% current yield) in ethanol containing 10 vol% of water [14]. 

Figure 5.10 Paired electrolysis to generate cation and anion equivalents using a...

Paired electrolysis [33], in which both the anodic oxidation and the cathodic reduction contribute to the formation of the final product(s), is highly advantageous from the viewpoint of green chemistry, because of the effidnet use of electric energy and avoidance of disposal of by-products produced at the counter electrode. 

It is noteworthy that both anodic and cathodic reactions can be used for desired transformations in some cases. For example, the anodic oxidation of silyl-substituted carbamates can be combined with the cathodic reduction of allyUc halides in the presence of chlorotrimethylsilane (paired electrolysis) [51]. The products of both reactions, i.e. N-acyliminium ion and the allylic silane, are then allowed to react with each other to obtain a final coupling product (Table 7.2). 

Cheng H, Scott K, Christensen PA (2005) Paired electrolysis in a solid polymer electrolyte reactor -simultaneously reduction of nitrate and oxidation of ammonia. Chem Eng J 108 257-268... 

Reyter D, Belanger D, Roue L (2011) Optimization of the cathode material for nitrate removal by a paired electrolysis process. J Hazard Mater 192 507-513... 

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