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The utilizations of omnipresent, thermodynamically stable amides and aliphatic C(sp3)−H bonds for various functionalizations are ongoing challenges in catalysis. In particular, the direct coupling between the two functional groups has not been realized. Here, we report the synergistic activation of the two challenging bonds, the amide C−N and unactivated aliphatic C(sp3)−H, via metallaphotoredox catalysis to directly acylate aliphatic C−H bonds utilizing amides as stable and readily accessible acyl surrogates. N‐acylsuccinimides served as efficient acyl reagents for the streamlined synthesis of synthetically useful ketones from simple C(sp3)−H substrates. Detailed mechanistic investigations using both computational and experimental mechanistic studies were performed to construct a detailed and complete catalytic cycle. The origin of the superior reactivity of the N‐acylsuccinimides over other more reactive acyl sources such as acyl chlorides was found to be an uncommon reaction pathway which commences with C−H activation prior to oxidative addition of the acyl substrate. [ABSTRACT FROM AUTHOR]

The utilizations of omnipresent, thermodynamically stable amides and aliphatic C(sp 3 )-H bonds for various functionalizations are ongoing challenges in catalysis. In particular, the direct coupling between the two functional groups has not been realized. Here, we report the synergistic activation of the two challenging bonds, the amide C-N and unactivated aliphatic C(sp 3 )-H, via metallaphotoredox catalysis to directly acylate aliphatic C-H bonds utilizing amides as stable and readily accessible acyl surrogates. N-acylsuccinimides served as efficient acyl reagents for the streamlined synthesis of synthetically useful ketones from simple C(sp 3 )-H substrates. Detailed mechanistic investigations using both computational and experimental mechanistic studies were performed to construct a detailed and complete catalytic cycle. The origin of the superior reactivity of the N-acylsuccinimides over other more reactive acyl sources such as acyl chlorides was found to be an uncommon reaction pathway which commences with C-H activation prior to oxidative addition of the acyl substrate., (© 2020 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The mechanistic platform for a novel nickel 0 -catalyzed anionic cross-coupling reaction (ACCR) of lithium sulfonimidoyl alkylidene carbenoids (metalloalkenyl sulfoximines) with organometallic reagents is reported herein, affording substituted alkenylmetals and lithium sulfinamides. The Ni 0 -catalyzed ACCR of three different types of metalloalkenyl sulfoximines, including acyclic, axially chiral and exocyclic derivatives, with sp 2 organolithiums and sp 2 and sp 3 Grignard reagents has been studied. The ACCR of metalloalkenyl sulfoximines with PhLi in the presence of the Ni 0 -catalyst and precatalyst Ni(PPh 3 ) 2 Cl 2 afforded alkenyllithiums, under inversion of configuration at the C atom and complete retention at the S atom. In a combination of experimental and DFT studies, we propose a catalytic cycle of the Ni 0 -catalyzed ACCR of lithioalkenyl sulfoximines. Computational studies reveal two distinctive pathways of the ACCR, depending on whether a phosphine or 1,5-cyclooctadiene (COD) is the ligand of the Ni atom. They rectify the underlying importance of forming the key Ni 0 -vinylidene intermediate through an indispensable electron-rich Ni 0 -center coordinated by phosphine ligands. Fundamentally, we present a mechanistic study in controlling the diastereoselectivity of the alkenyllithium formation via the key lithium sulfinamide coordinated Ni 0 -vinylidene complex, which consequently avoids an unselective formation of an alkylidene carbene Ni-complex and ultimately racemic alkenyllithium., (© 2019 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.)