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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.
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Three-Component Ni-Catalyzed Silylacylation of Alkenes
A Ni-catalyzed silylacylation of alkenes is presented. The reaction combines alkenes, ClZnSiR3, and acid chlorides to provide rapid access to β-silyl ketones. Importantly, the method involves a [Ni]-SiR3 complex as a catalytic intermediate, which is rarely described for three-component alkene functionalization. Finally, the synthetic utility of the products is demonstrated, and the mechanistic details are described.
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- Award ID(s):
- 1726633
- PAR ID:
- 10212740
- Date Published:
- Journal Name:
- ACS Catalysis
- ISSN:
- 2155-5435
- Page Range / eLocation ID:
- 1858 to 1862
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1021/acscatal.0c05449
