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Photocatalysis holds a pivotal position in modern organic synthesis, capable of inducing novel reactivities under mild and environmentally friendly reaction conditions. However, the merger of photocatalysis and transition‐metal‐catalyzed asymmetric C−H activation as an efficient and sustainable method for the construction of chiral molecules remains elusive and challenging. Herein, we develop a cobalt‐catalyzed enantioselective C−H activation reaction enabled by visible‐light photoredox catalysis, providing a synergistic catalytic strategy for the asymmetric dearomatization of indoles with high levels of enantioselectivity (96 % to >99 % ee). Mechanistic studies indicate that the excited photocatalyst was quenched by divalent cobalt species in the presence of Salox ligand, leading to the formation of catalytically active chiral Co(III) complex. Moreover, stoichiometric reactions of cobaltacycle intermediate with indole suggest that the irradiation of visible light also play a critical role in the dearomatization step. [ABSTRACT FROM AUTHOR]

The combination of achiral Cp*Rh(III) with chiral carboxylic acids (CCAs) represents an efficient catalytic system in transition metal‐catalyzed enantioselective C−H activation. However, this hybrid catalysis is limited to redox‐neutral C−H activation reactions and the adopt to oxidative enantioselective C−H activation remains elusive and pose a significant challenge. Herein, we describe the development of an electrochemical Cp*Rh(III)‐catalyzed enantioselective C−H annulation of sulfoximines with alkynes enabled by chiral carboxylic acid (CCA) in an operationally friendly undivided cell at room temperature. A broad range of enantioenriched 1,2‐benzothiazines are obtained in high yields with excellent enantioselectivities (up to 99 % yield and 98 : 2 er). The practicality of this method is demonstrated by scale‐up reaction in a batch reactor with external circulation. A crucial chiral Cp*Rh(III) intermediate is isolated, characterized, and transformed, providing rational support for a Rh(III)/Rh(I) electrocatalytic cycle. [ABSTRACT FROM AUTHOR]

Transition metal‐catalyzed enantioselective C−H carbonylation with carbon monoxide, an essential and easily available C1 feedstock, remains challenging. Here, we disclosed an unprecedented enantioselective C−H carbonylation catalyzed by inexpensive and readily available cobalt(II) salt. The reactions proceed efficiently through desymmetrization, kinetic resolution, and parallel kinetic resolution, affording a broad range of chiral isoindolinones in good yields with excellent enantioselectivities (up to 92 % yield and 99 % ee). The synthetic potential of this method was demonstrated by asymmetric synthesis of biological active compounds, such as (S)‐PD172938 and (S)‐Pazinaclone. The resulting chiral isoindolinones also serve as chiral ligands in cobalt‐catalyzed enantioselective C−H annulation with alkynes to construct phosphorus stereocenter. [ABSTRACT FROM AUTHOR]

P-Stereogenic phosphorus compounds are important structural elements in chiral ligands or organocatalysts. Herein, we report a Pd(II)-catalyzed enantioselective C–H olefination toward the synthesis of P-stereogenic phosphinamides using cheap commercially available L -pGlu-OH as a chiral ligand. A broad range of P-stereogenic phosphinamides were gained in good yields with high enantioselectivities (33 examples, up to 77% yield, 99% ee) via desymmetrization and kinetic resolution. [ABSTRACT FROM AUTHOR]

Herein, we reported the synthesis of enantioenriched N-aryl peptoid atropisomers via Pd(II)-catalyzed atroposelective C–H olefination using the easily accessible L -pyroglutamic acid (L -pGlu-OH) as the chiral ligand. A series of optically active N-aryl peptoid atropisomers were obtained in synthetically useful yields with high enantioselectivities. [ABSTRACT FROM AUTHOR]

Axially chiral styrenes, a type of atropisomer analogous to biaryls, have attracted great interest because of their unique presence in natural products and asymmetric catalysis. Since 2016, a number of methodologies have been developed for the atroposelective construction of these chiral skeletons, involving both transition metal catalysis and organocatalysis. In this feature article, we aim to provide a comprehensive understanding of recent advances in the asymmetric synthesis of axially chiral styrenes catalyzed by transition metals, integrating scattered work with different catalytic systems together. This feature article is cataloged into five sections according to the strategies, including asymmetric coupling, enantioselective C–H activation, central-to-axial chirality transfer, asymmetric alkyne functionalization, and atroposelective [2+2+2] cycloaddition. [ABSTRACT FROM AUTHOR]

Metalla‐electrocatalyzed C−H oxygenation represents one of the most straightforward and sustainable approaches to access valuable oxygenated molecules. Despite the significant advances, the development of enantioselective electrochemical C−H oxygenation reaction is very challenging and remains elusive. Herein, we described the first electrochemical CoII‐catalyzed enantioselective C−H alkoxylation. A broad range of enantioenriched alkoxylated phosphinamides were obtained in good yields with excellent enantioselectivities (up to 98 % yield and >99 % ee). An unusual cobalt(III) alcohol complex was prepared and fully characterized, which was proven to be a key intermediate of this C−H alkoxylation reaction. Mechanistic studies revealed that the oxidation of CoIII to CoIV was facilitated by a base and the whole process proceeded through a cobalt(III/IV/II) catalytic cycle. [ABSTRACT FROM AUTHOR]