Dechlorination of chloroethylenes by cob(I)alamin and cobalamin model complexes

Cobalt-mediated dehalogenation reactions, specifically those that employ cobalamin, have attracted particular attention because these complexes rapidly degrade tetrachloroethylene (PCE) and trichloroethylene (TCE), which are common groundwater contaminants. Although questions remain about the relative importance of several pathways, both radicals and organometallic intermediates, specifically chlorovinyl complexes, play an important role in these processes. This Perspective highlights recent studies focused on elucidating the mechanism of chloroethylene degradation, including experimental studies on PCE and TCE dechlorination, computational studies, preparation of model complexes, and the study of model catalytic systems.