Serial Electrode Configuration

Figure 9.1 Cyanation of pyrene in an electrochemical flow microreactor with a serial electrode configuration.

There is another type of electrochemical flow microreactors that can be used for electrolyte-free electrolysis (Figure 9.5) [24]. In this system, two carbon fiber electrodes are separated by a spacer (porous PTFE membrane, pore size 3 pm, thickness 75 pm) at a distance of micrometer order. A substrate solution is introduced into the anodic chamber. The anodic solution flows through the spacer membrane into the cathodic chamber. The product solution leaves the system from the cathodic chamber. In this system, the electric current flow and the liquid flow are parallel. Using this electrochemical flow microreactor having a serial electrode configuration, the anodic methoxylation of p-methoxytoluene was accomplished effectively without intentionally added electrolyte. Protons generated by the anodic oxidation acted as carriers of the electricity. This process will be discussed in detail in the practical part of this chapter. The device could also be used for the anodic methoxylation of N-methoxycarbonyl pyrrolidine and acenaphthylene. 

Reaction System Anodic oxidation of p-methoxytoluene is carried out in the absence of intentionally added supporting electrolyte using an electrochemical flow microreactor with a serial electrode configuration to obtain p-methoxyben-zaldehyde dimethyl acetal. 

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