VOLTAMMETRY OF POLYBROMOMETHANES IN APROTIC-SOLVENTS

Reduction of CBr4, CHBr3, and CH2Br2 on a glassy-carbon rotating disk electrode in dimethylformamide and acetonitrile proceeds mainly via su ccessive dehalogenation. Anions -CBr3 and -CHBr2, formed in the first reduction step of CBr4 and CHBr3, respectively, can undergo both proto nation (through reaction -CHBr2 + CHBr3 --> CH2Br2 + -CBr3, among othe rs) and partial dissociation to fragments by the pattern -CBr3 --> :CB r2 + Br- (with subsequent reduction of carbene at the same potentials) . Concurrently, compounds form that inhibit the reduction process. The reduction of polybromomethanes on mercury is complicated by their int eraction with the electrode material.