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Intermolecular C−H silylation for the synthesis of acyclic silanes bearing a silicon‐stereogenic center in one enantiomeric form remains unknown to date. Herein, we report the first enantioselective intermolecular C−H silylation of heteroarenes for the synthesis of acyclic silicon‐stereogenic heteroarylsilanes. This process undergoes a rhodium‐catalyzed direct intermolecular dehydrogenative Si−H/C−H cross‐coupling, giving access to a variety of acyclic heteroarylated silicon‐stereogenic monohydrosilanes, including bis‐Si‐stereogenic silanes, in decent yields with excellent chemo‐, regio‐, and stereo‐control, which significantly enlarge the chemical space of the optically active silicon‐stereogenic monohydrosilanes. [ABSTRACT FROM AUTHOR]

Previous direct C−H nitrogenation suffered from simple amidation/amination with limited atom-economy and is mostly limited to C(sp2)−H substrates. In this work, anthranil was designed as a novel bifunctional aminating reagent for both C(sp2)−H and C(sp3)−H bonds under rhodium(III) catalysis, thus affording a nucleophilic aniline tethered to an electrophilic carbonyl. A tridendate rhodium(III) complex has been isolated as the resting state of the catalyst, and DFT studies established the intermediacy of a nitrene species. [ABSTRACT FROM AUTHOR]

Metal-catalyzed CH activation not only offers important strategies to construct new bonds, it also allows the merge of important research areas. When quinoline N-oxide is used as an arene source in CH activation studies, the NO bond can act as a directing group as well as an O-atom donor. The newly reported density functional theory method, M11L, has been used to elucidate the mechanistic details of the coupling between quinoline NO bond and alkynes, which results in CH activation and O-atom transfer. The computational results indicated that the most favorable pathway involves an electrophilic deprotonation, an insertion of an acetylene group into a RhC bond, a reductive elimination to form an oxazinoquinolinium-coordinated RhI intermediate, an oxidative addition to break the NO bond, and a protonation reaction to regenerate the active catalyst. The regioselectivity of the reaction has also been studied by using prop-1-yn-1-ylbenzene as a model unsymmetrical substrate. Theoretical calculations suggested that 1-phenyl-2-quinolinylpropanone would be the major product because of better conjugation between the phenyl group and enolate moiety in the corresponding transition state of the regioselectivity-determining step. These calculated data are consistent with the experimental observations. [ABSTRACT FROM AUTHOR]

Asymmetric Catalysis, Dehydrogenative Coupling, Rhodium, Silylation, Stereogenic Silanes Keywords: Asymmetric Catalysis; Dehydrogenative Coupling; Rhodium; Silylation; Stereogenic Silanes EN Asymmetric Catalysis Dehydrogenative Coupling Rhodium Silylation Stereogenic Silanes 1 1 1 05/11/22 20220516 NES 220516 B Asymmetrische Katalyse b In ihrer Zuschrift (e202117820) berichten Chuan He et al. über die enantioselektive intermolekulare C-H-Silylierung von Heteroarenen zur Synthese von azyklischen Si-stereogenen Silanen. Frontispiz: Enantioselective Intermolecular C-H Silylation of Heteroarenes for the Synthesis of Acyclic Si-Stereogenic Silanes. [Extracted from the article]