A cyclic voltammogram for the reduction of 4-(bromomethyl)-7-methyl-2H-chromen-2-one (1) at a glassy carbon cathode in dimethylformamide containing tetramethylammonium tetrafluoroborate shows irreversible peaks that can be attributed to reductive cleavage of the carbon-bromine bond and to reduction of two products, namely 4,7-dimethyl-2H-chromen-2-one (3) and 4,4'-(ethane-l,2-diyl)bis(7-methyl-2H-chromen-2-one) (5). In a similar fashion, cyclic voltammograms for the reduction of 4-(bromomethyl)-7-methoxy-2H-chromen-2-one (2) can be interpreted in terms of scission of the carbon-bromine bond as well as the reductions of 7-methoxy-4-methyl-2H-chromen-2-one (4) and 4,4'-(ethane-1,2-diyl)bis(7-methoxy-2H-chromen-2-one) (6). Controlled-potential (bulk) electrolyses of 1 or 2 at reticulated vitreous carbon cathodes held at potentials corresponding to reduction of the carbon-bromine bond afford 3 or 4, respectively, in yields of 19-25%, along with 5 or 6, respectively, in yields of 70-81%. On the basis of the coulometric n value of one, it is concluded that the carbon-bromine bond of 1 or 2 undergoes one-electron reduction to the corresponding radical, which either accepts a hydrogen atom from the solvent or couples with itself. (C) 2008 The Electrochemical Society.