Addition Reactions of Cathodically Generated Radicals

Radicals generated at the cathode by either direct or indirect reduction (see also Section 2.6.5.2) have been added to alkenes, aromatic compounds, pyridinium salts, nitriles, alkynes, carbon and metals. 

The cathodic cyclization of 5-enones leads regio- and stereoselectively to cyclo-pentanols (Eqs. 22, 23) [161]. The reduction of the non-conjugated dienone affords in a tandem reaction a bicyclic alcohol (Eq. 24) [162]. 

Enol phosphates can be reduced to vinyl radicals, which cyclize in a tandem reaction to cyclopropanes (Eq. 25) [163], 

In /fM-generated acylphosphonium salts can be reduced to the corresponding ketyls, which cyclize to a-substituted cyclopentanones (Eq. 28) [166.  

Aryl radicals that are generated by cathodic reduction of aryl halides have been added to phenols [167]. With aromatic radical anions as mediators, the follow-up reduction of aryl radicals can be suppressed, which enables the cathodic addition of 

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