Dihalides electroreduction

The electroreductive coupling of organic dihalides is an interesting approach to synthesize polymers. 

Organic Electroreductive Coupling Reactions using Transition Metal Complexes as Catalysts Table 2. Reductive electropolymerisation of aryl dihalides using nickel catalysts... 

The high yield reduction of 1,2-dihalides to produce olefins has been employed to advantage to prepare reactive olefins. Electron transfer in electrochemistry is proportional to the diffusion coefficient, which is related in a much less sensitive way to temperature changes than is chemical reactivity. Thus it may become possible to synthesize and study electro-chemically species whose chemical reactivity is high by working at low temperatures. Electroreduction of 1,2-dibromobenzocyclobutene (144) in acetonitrile or butyroni-trile/TEAP or chemical reduction using the biphenyl radical anion resulted in the formation of benzocyclobutadiene (145)128. Efforts to observe the electrochemically generated anion radical or dianion of benzocyclobutadiene indicated that dimerization to 146 was faster than further reduction (equation 84). 

Monomeric and polymeric A-alkylpyridine-4-carboxylates serve as redox mediators for the indirect electroreduction of z /c-dihalides to PYWj -olefins [219,220]. 

Aromatic 1,2-dihalides (I, Br) gave only traces of benzyne on gas-phase reaction with alkali metal vapors under microwave or ultrasound excitation. Electroreduction of such... 

Electroreductive dehalogenation of v/c-dihalides using a Co(II)salen complex in [BMIMllBFq] was... 

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