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Abstract C−C linked glutarimide‐containing structures with direct utility in the preparation of cereblon‐based degraders (PROTACs, CELMoDs) can be assessed in a single step from inexpensive, commercial α‐bromoglutarimide through a unique Brønsted‐acid assisted Ni‐electrocatalytic approach. The reaction tolerates a broad array of functional groups that are historically problematic and can be applied to the simplified synthesis of dozens of known compounds that have only been procured through laborious, wasteful, multi‐step sequences. The reaction is scalable in both batch and flow and features a trivial procedure wherein the most time‐consuming aspect of reaction setup is weighing out the starting materials. 

Abstract There is a pressing need, particularly in the field of drug discovery, for general methods that will enable direct coupling of tertiary alkyl fragments to (hetero)aryl halides. Herein a uniquely powerful and simple set of conditions for achieving this transformation with unparalleled generality and chemoselectivity is disclosed. This new protocol is placed in context with other recently reported methods, applied to simplify the routes of known bioactive building blocks molecules, and scaled up in both batch and flow. The role of pyridine additive as well as the mechanism of this reaction are interrogated through Cyclic Voltammetry studies, titration experiments, control reactions with Ni(0) and Ni(II)‐complexes, and ligand optimization data. Those studies indicate that the formation of a BINAPNi(0) is minimized and the formation of an active pyridine‐stabilized Ni(I) species is sustained during the reaction. Our preliminary mechanistic studies ruled out the involvement of Ni(0) species in this electrochemical cross‐coupling, which is mediated by Ni(I) species via a Ni(I)‐Ni(II)‐Ni(III)‐Ni(I) catalytic cycle.