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Abstract A three‐component coupling approach toward structurally complex dialkylsulfides is described via the nickel‐catalyzed 1,2‐carbosulfenylation of unactivated alkenes with organoboron nucleophiles and alkylsulfenamide (N−S) electrophiles. Efficient catalytic turnover is facilitated using a tailored N−S electrophile containing anN‐methyl methanesulfonamide leaving group, allowing catalyst loadings as low as 1 mol %. Regioselectivity is controlled by a collection of monodentate, weakly coordinating native directing groups, including sulfonamides, amides, sulfinamides, phosphoramides, and carbamates. Key to the development of this transformation is the identification of quinones as a family of hemilabile and redox‐active ligands that tune the steric and electronic properties of the metal throughout the catalytic cycle. Density functional theory (DFT) results show that the duroquinone (DQ) ligand adopts different coordination modes in different stages of the Ni‐catalyzed 1,2‐carbosulfenylation‐binding as an η⁶capping ligand to stabilize the precatalyst/resting state and prevent catalyst decomposition, binding as an X‐type redox‐active durosemiquinone radical anion to promote alkene migratory insertion with a less distorted square planar Ni(II) center, and binding as an L‐type ligand to promote N−S oxidative addition at a relatively more electron‐rich Ni(I) center. 

Abstract Over the last fifty years, the use of nickel catalysts for facilitating organic transformations has skyrocketed. Nickel(0) sources act as useful precatalysts because they can enter a catalytic cycle through ligand exchange, without needing to undergo additional elementary steps. However, most Ni(0) precatalysts are synthesized with stoichiometric aluminum–hydride reductants, pyrophoric reagents that are not atom‐economical and must be used at cryogenic temperatures. Here, we demonstrate that Ni(II) salts can be reduced on preparative scale using electrolysis to yield a variety of Ni(0) and Ni(II) complexes that are widely used as precatalysts in organic synthesis, including bis(1,5‐cyclooctadiene)nickel(0) [Ni(COD)₂]. This method overcomes the reproducibility issues of previously reported methods by standardizing the procedure, such that it can be performed anywhere in a robust manner. It can be transitioned to large scale through an electrochemical recirculating flow process and extended to an in situ reduction protocol to generate catalytic amounts of Ni(0) for organic transformations. We anticipate that this work will accelerate adoption of preparative electrochemistry for the synthesis of low‐valent organometallic complexes in academia and industry.