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Previous methods on CoIII‐catalyzed asymmetric C−H activation rely on the use of tailor‐made cyclopentadienyl‐ligated CoIII complexes, which require lengthy steps for the preparation. Herein, we report an unprecedented enantioselective C−H functionalization enabled by a simple cobalt/salicyloxazoline (Salox) catalysis. The chiral Salox ligands can be easily prepared in one step from salicylonitrile and chiral amino alcohols. A broad range of P‐stereogenic compounds were synthesized in high yields with excellent enantioselectivities (45 examples, up to 99 % yield and >99 % ee). The isolation and characterization of several intermediates provided insights into the generation of active catalytic cobalt species, the action of Salox, and the mode of stereocontrol. [ABSTRACT FROM AUTHOR]

Previous methods on CoIII‐catalyzed asymmetric C−H activation rely on the use of tailor‐made cyclopentadienyl‐ligated CoIII complexes, which require lengthy steps for the preparation. Herein, we report an unprecedented enantioselective C−H functionalization enabled by a simple cobalt/salicyloxazoline (Salox) catalysis. The chiral Salox ligands can be easily prepared in one step from salicylonitrile and chiral amino alcohols. A broad range of P‐stereogenic compounds were synthesized in high yields with excellent enantioselectivities (45 examples, up to 99 % yield and >99 % ee). The isolation and characterization of several intermediates provided insights into the generation of active catalytic cobalt species, the action of Salox, and the mode of stereocontrol. [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]

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]

In recent years, the merging of electrosynthesis with 3d metal catalyzed C−H activation has emerged as a sustainable and powerful technique in organic synthesis. Despite the impressive advantages, the development of an enantioselective version remains elusive and poses a daunting challenge. Herein, we report the first electrooxidative cobalt‐catalyzed enantio‐ and regioselective C−H/N−H annulation with olefins using an undivided cell at room temperature (up to 99 % ee). tBu‐Salox, a rationally designed Salox ligand bearing a bulky tert‐butyl group at the ortho‐position of phenol, was found to be crucial for this asymmetric annulation reaction. A strong cooperative effect between tBu‐Salox and 3,4,5‐trichloropyridine enabled the highly enantio‐ and regioselective C−H annulation with the more challenging α‐olefins without secondary bond interactions (up to 96 % ee and 97 : 3 rr). Cyclovoltametric studies, and the preparation, characterization, and transformation of cobaltacycle intermediates shed light on the mechanism of this reaction. [ABSTRACT FROM AUTHOR]

In recent years, the merging of electrosynthesis with 3d metal catalyzed C−H activation has emerged as a sustainable and powerful technique in organic synthesis. Despite the impressive advantages, the development of an enantioselective version remains elusive and poses a daunting challenge. Herein, we report the first electrooxidative cobalt‐catalyzed enantio‐ and regioselective C−H/N−H annulation with olefins using an undivided cell at room temperature (up to 99 % ee). tBu‐Salox, a rationally designed Salox ligand bearing a bulky tert‐butyl group at the ortho‐position of phenol, was found to be crucial for this asymmetric annulation reaction. A strong cooperative effect between tBu‐Salox and 3,4,5‐trichloropyridine enabled the highly enantio‐ and regioselective C−H annulation with the more challenging α‐olefins without secondary bond interactions (up to 96 % ee and 97 : 3 rr). Cyclovoltametric studies, and the preparation, characterization, and transformation of cobaltacycle intermediates shed light on the mechanism of this reaction. [ABSTRACT FROM AUTHOR]

Previous methods on CoIII‐catalyzed asymmetric C−H activation rely on the use of tailor‐made cyclopentadienyl‐ligated CoIII complexes, which require lengthy steps for the preparation. Herein, we report an unprecedented enantioselective C−H functionalization enabled by a simple cobalt/salicyloxazoline (Salox) catalysis. The chiral Salox ligands can be easily prepared in one step from salicylonitrile and chiral amino alcohols. A broad range of P‐stereogenic compounds were synthesized in high yields with excellent enantioselectivities (45 examples, up to 99 % yield and >99 % ee). The isolation and characterization of several intermediates provided insights into the generation of active catalytic cobalt species, the action of Salox, and the mode of stereocontrol. [ABSTRACT FROM AUTHOR]