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The direct reductive cross-electrophile coupling (XEC) of two electrophiles has emerged as an attractive alternative to traditional cross coupling methodologies. These new XEC methods avoid the multistep prefunctionalization and use of highly reactive organometallic intermediates. The exclusion of such high-energy species often leads to improved functional group compatibility and can be conducted in atmospheric conditions. However, the limited substrate scope, requirement of low-potential redox-active catalysts, and use of superstoichiometric quantities of metal-based reductants or expensive chemical reductants have precluded the application of XEC in industrial settings.As a result, electrochemical methods have garnered attention over the past few years because it substitutes expensive, exogeneous redox reagents for benign low-energy materials. Electrochemical methodologies allow direct tuning of the catalyst and enable judicious control of the potential at which each electron is delivered, often at higher potentials than the source of the electron or hole. Although electrochemistry offers an innovative solution to the problems that plague XEC, electroreductive XEC reactions (eXEC) remain rare.Our efforts toward new eXEC technologies have been centered around the eXEC of aryl and alkyl bromides. More specifically, the selective coupling of challenging aryl electrophiles has remained limited because typical coupling catalysts are weakly reducing. The use of low-potential catalysts stem from the set reduction potentials of common XEC reductants. We hypothesized that electrochemistry would enable the delivery of high energy electrons needed to activate more activated catalysts. Our initial approach focused on repurposing a ligand used in battery materials toward eXEC. Thorough mechanistic investigation involving isolation and analysis of low-valent metal enabled the identification of aryl bromide over-reduction as major decomposition pathway. This led to the first application of redox-active shuttles in organic synthesis to enable the selective coupling of aryl and 1° with 2° alkyl bromides (Chapter 2).Subsequent studies were focused on expanding this work to enable the eXEC of 3° alkyl bromides. Recent reports had led to a reevaluation of the XEC mechanism and implicated NiI as the catalytic intermediate responsible for activating both alkyl and aryl halides. Thus, XEC of highly reactive 3° alkyl bromides often result in preferential 3° bromide activation. Critical to the success of this methodology was the application of a dual-catalyst system in which each catalyst activates a single electrophile. Ligand design was centered around targeting specific redox states of Ni to bias each catalyst toward one substrate. Detailed mechanistic studies uncovered “ligand rebound” as a novel mechanism in XEC reactions. Guided by these mechanistic insights, a wide scope of traditionally-incompatible substrates was developed (Chapter 3).Although this represented a general solution to the XEC of aryl electrophiles and alkyl halides, application of this methodology to other common radical precursors ultimately failed. Stoichiometric analysis revealed that Ni-Ar complexes readily capture and couple alkyl radicals generated in situ from a wide variety of radical precursors. We recognized that applying this method to Ni-Ar intermediates bearing pharmaceutically-relevant arenes would enable the rapid diversification of complex intermediates from a single stable precursor. This work is the subject of Chapter 4.