Control of Redox‐Active Ester Reactivity Enables a General Cross‐Electrophile Approach to Access Arylated Strained Rings**

Strained rings are increasingly important for the design of pharmaceutical candidates, but cross-coupling strained remains challenging. An attractive, underdeveloped, approach to diverse functionalized carbocyclic and heterocyclic frameworks containing all-carbon quaternary centers is coupling abundant strained-ring carboxylic acids with aryl halides. Herein we disclose development a nickel-catalyzed cross-electrophile that couples variety ring N-hydroxyphthalimide (NHP) esters, derived from acid in one step, various heteroaryl halides under reductive conditions. The chemistry enabled by discovery methods control NHP ester reactivity, tuning solvent or using modified t-BuBpyCamCN, an L2X ligand, avoids problematic side reactions. This method can be run flow 96-well plates.