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The past decade has witnessed a rapid progress in asymmetric C-H activation. However, the enantioselective C-H alkoxylation and amination with alcohols and free amines remains elusive. Herein, we disclose the first enantioselective dehydrogenative C-H alkoxylation and amination enabled by a simple cobalt/salicyloxazoline (Salox) catalysis. The use of cheap and readily available cobalt(II) salts as catalysts and Saloxs as chiral ligands provides an efficient method to access P-stereogenic compounds in excellent enantioselectivities (up to >99 % ee). The practicality of this protocol is demonstrated by gram-scale preparation and further derivatizations of the resulting P-stereogenic phosphinamides, which offering a flexible asymmetric alternative to access P-stereogenic mono- and diphosphine chiral ligands. Preliminary mechanistic studies on the enantioselective C-H alkoxylation reaction suggest that a cobalt(III/IV/II) catalytic cycle might be involved., (© 2022 Wiley-VCH GmbH.)

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]

Highly efficient synthesis of axially chiral biaryl amines through cobalt‐catalyzed atroposelective C−H arylation using easily accessible cobalt(II) salt and salicyloxazoline ligand has been reported. This methodology provides a straightforward and sustainable access to a broad range of enantioenriched biaryl‐2‐amines in good yields (up to 99 %) with excellent enantioselectivities (up to 99 % ee). The synthetic utility of the unprecedented method is highlighted by its scalability and diverse transformations. [ABSTRACT FROM AUTHOR]

Chiral diarylmethylamines (DAMA) are important structural motifs widely present in pharmaceuticals, natural products, and chiral ligands. Herein, we reported a highly enantioselective synthesis of chiral DAMAs via cobalt‐catalyzed enantioselective C−H alkoxylation strategy. The reaction features easy operation, the use of earth‐abundant and cost‐efficient cobalt(II) catalyst, and readily available ligand. A range of chiral DAMAs were efficiently synthesized in high yields with excellent enantioselectivities (up to 90 % yield and up to 99 % ee) through desymmetrization and parallel kinetic resolution. Moreover, this protocol was also compatible with the synthesis of chiral benzylamines via kinetic resolution. [ABSTRACT FROM AUTHOR]

The past decade has witnessed a rapid progress in asymmetric C−H activation. However, the enantioselective C−H alkoxylation and amination with alcohols and free amines remains elusive. Herein, we disclose the first enantioselective dehydrogenative C−H alkoxylation and amination enabled by a simple cobalt/salicyloxazoline (Salox) catalysis. The use of cheap and readily available cobalt(II) salts as catalysts and Saloxs as chiral ligands provides an efficient method to access P‐stereogenic compounds in excellent enantioselectivities (up to >99 % ee). The practicality of this protocol is demonstrated by gram‐scale preparation and further derivatizations of the resulting P‐stereogenic phosphinamides, which offering a flexible asymmetric alternative to access P‐stereogenic mono‐ and diphosphine chiral ligands. Preliminary mechanistic studies on the enantioselective C−H alkoxylation reaction suggest that a cobalt(III/IV/II) catalytic cycle might be involved. [ABSTRACT FROM AUTHOR]