Methyl halide electroreduction

The group at Tokyo Institute of Technology have also examined the electroreduction of methyl halides at a reactive tin cathode [198]. This is a different type of electrochemical system in which the cathode is a reactive metal. A surface intermediate is formed on the electrode which reacts to give either a three-electron dimeric distannane or a four-electron tetramethyl stannane, as shown in Scheme 9. 

ET-initiated alkylation of azines in the presence of alkyl halides has been found to occur under electrochemical conditions according to Scheme 43. Either alkylated dihydroheterocycles or the rearomatized products are obtained. As an example, electroreduction of quinoline in the presence of 1-bromoadamantane gives alkylated quinolines (10 % in position 2, 5 % in position 7) and 2-methyl- and 2-methoxyquinoline give the 7-adamantyl derivative in 20 and 23 % yield, respectively. 1,10-Phenanthroline gives bis(adamantyl) derivatives, whereas isoquinoline and phenanthridine give the 6-adamantyl-5,6-dihydro and the 9-adamantyl-9,10-dihydro derivatives, respectively [132]. Reaction with terr-butyl chloride also gives alkylated dihydroheterocycles [133]. Arylation has also been performed, e.g. in the synthesis of pyrazolophenanthridines (62, Scheme 44) [134]. 

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