For Electroorganic Synthesis

KF/A1203 is widely used as a solid base in a wide variety of reactions, whereas application of CsF/Al203 to organic reactions is not so well reported. Figueras 

Figu re 5.2 Electrolytic system using solid-supported bases for in situ generation of a supporting electrolyte. 

CsF/A1203 was also used for deacylation reactions [48]. Among several inorganic supported CsF systems, Celite-supported CsF has been used for many reactions, such as N-alkylaliori, oxidation of thiols, addition reaction and Williamson synthesis [49-54]. 

KOH/kaolin combined with a chiral catalyst was used for asymmetric alkylation of glycine imine esters, and recycled for subsequent reactions without loss of activity over three times [55, 56]. 

Asymmetric synthesis of P-phosphono-malonates via K0H/Fe203 catalyzed phospha-Michael reaction to Knoevenagel acceptors has been achieved by Enders and Tedeschi [57]. The reaction did not proceed when only KOH was used as a catalyst Fe203 was the best diastereoselective support among the other supports tested, A1203, ZnO, Cu20, Mn02 and MgO. 

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Electrodes. At least three factors need to be considered ia electrode selection as the technical development of an electroorganic reaction moves from the laboratory cell to the commercial system. First is the selection of the lowest cost form of the conductive material that both produces the desired electrode reactions and possesses stmctural iategrity. Second is the preservation of the active life of the electrodes. The final factor is the conductivity of the electrode material within the context of cell design. An ia-depth discussion of electrode materials for electroorganic synthesis as well as a detailed discussion of the influence of electrode materials on reaction path (electrocatalysis) are available (25,26). A general account of electrodes for iadustrial processes is also available (27). 

Tank Cells. A direct extension of laboratory beaker cells is represented in the use of plate electrodes immersed into a lined, rectangular tank, which may be fitted with a cover for gas collection or vapor control. The tank cell, which is usually undivided, is used in batch or semibatch operations. The tank cell has the attraction of being both simple to design and usually inexpensive. However, it is not the most suitable for large-scale operation or where forced convection is needed. Rotating cylinders or rotating disks have been used to overcome mass-transfer problems in tank cells. An example for electroorganic synthesis is available (46). 

Stark, W., Kinkel, J., Michel, M., Schmidt-Traub, H., Micro reactor for electroorganic synthesis in the simulated moving bed-reaction and separation environment, Electrochim. Acta 48 (2003) 2889-2896. 

Water is one of the most environmentally friendly solvents, and the use of water as a solvent for electroorganic synthesis seems to be attractive, although many organic... 

Ionic liquids have also attracted significant research interest as environmentally benign reaction media because they are expected to replace hazardous and volatile organic solvents. The advantages of ionic liquids include easy recovery and re-use, in addition to minuscule vapor pressure, nonflammability, and relative inertness. For electroorganic synthesis, ionic liquids serve as good reaction media, because they have relatively wide potential windows and high conductivity. Because ionic liquids... 

Solid-liquid biphasic systems that utilizes reagents or catalysts bound to insoluble materials are also an effective approach. Various mediators and carriers of electricity bound to insoluble materials have been developed for electroorganic synthesis. We discuss such approaches in this section. 

Electroreduction of nitro compounds is of considerable importance for electroorganic synthesis. Interesting catalytic effects were reported for the reduction of aromatic nitro compounds on Pt. Figure 11 shows that Ph, Tl, and Bi adlayers shift the half-wave potential positively by 100 to 300 mV. The catalytic effect was attributed to a change in the mechanism of the reduction of the nitro group from a catalytic hydrogenation on bare Pt to an electron-transfer mechanism on Pt/Mad, that is, a direct electron exchange between the nitro compound and the adatom-covered electrode surface, namely. 

Bouzek K, Jiricny V, Kodym R, Kristal J, Bystron T (2010) Microstructured reactor for electroorganic synthesis. Electrochim Acta 55 8172-8181... 

Waldvogel SR, Mentizi S. Kirste A (2012) Boron-doped diamond electrodes for electroorganic synthesis. Topics Curr Chem 320 1-32... 

Furthermore, the oxidation products depend on the experimental conditions. In fact, it has been found that either the partial oxidation of the organic compound, for electroorganic synthesis, or the complete oxidation, for wastewater treatment. 

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