Pierre. H. Dixneuf

Despite the significant potential of chiral sulfinamides in drug discovery, the stereocontrolled synthesis of such molecules remains a formidable challenge. Herein, we report a nickel-catalyzed regio- and enantioselective hydrosulfinamidation of readily available aryl alkenes that provides efficient access to diverse chiral sulfinamides bearing two contiguous stereocenters. This method exhibits broad functional group tolerance, complete regioselectivity, and excellent enantioselectivity (up to 98% ee). The reaction is readily scalable to gram quantities, and the resulting products can be further transformed into a variety of sulfur-containing compounds with full retention of enantiopurity. Mechanistic studies elucidate the radical reaction pathway and rationalize the origins of regio- and enantioselectivity. The process commences with the regio- and enantioselective syn-hydronickelation of the alkene by an in situ-generated Ni(II)-H species, yielding an alkylnickel intermediate. Subsequently, a turnover-limiting step occurs through 2,3-addition of the alkylnickel species across the S═N bond of the sulfinylamines.

Despite the significant potential of axially chiral enamines, their efficient synthesis remains a challenge. Herein, we report a new approach for the diverse synthesis of enamine‐based axially chiral styrenes via a copper‐catalyzed atroposelective hydroamination of internal alkynes. This method features good functional group tolerance, exclusive regio‐ and E ‐selectivity, and excellent enantioselectivities (up to 98% ee). Experimental and DFT studies were performed to elucidate the mechanism and rationalize the origin of enantioselectivity. Furthermore, the reaction is readily scalable to gram quantities, and the resulting products can be transformed into chiral N,P‐ligands, thereby enriching the family of axially chiral ligands with new members.

Despite the significant potential of axially chiral enamines, their efficient synthesis remains a challenge. Herein, we report a new approach for the diverse synthesis of enamine‐based axially chiral styrenes via a copper‐catalyzed atroposelective hydroamination of internal alkynes. This method features good functional group tolerance, exclusive regio‐ and E ‐selectivity, and excellent enantioselectivities (up to 98% ee). Experimental and DFT studies were performed to elucidate the mechanism and rationalize the origin of enantioselectivity. Furthermore, the reaction is readily scalable to gram quantities, and the resulting products can be transformed into chiral N,P‐ligands, thereby enriching the family of axially chiral ligands with new members.

Despite their significant importance in numerous fields, the challenges in direct and diverse synthesis of γ-amino-α-hydroxybutyric acids (AHBAs) pose substantial obstacles to explore their functions. Here, by preparation of a N-doped carbon-supported bifunctional cobalt catalyst (Co-DAPhen/C), it was applied to develop a reductive tandem reaction for general synthesis of AHBA derivatives from cheap and abundant nitroarenes, formaldehyde, and acrylates. This catalytic three-component reaction features broad substrate and functionality tolerance, an easily accessible and reusable catalyst, and high step and atom economy. The active Co sites of the catalyst are involved in the mild reduction processes with formic acid, whereas the N-doped carbon support enriches the HCHO and acrylates by physical adsorption, thus favoring the capture of hydroxylamine and nitrone intermediates via condensation and 1,3-dipolar cycloaddition, respectively. Such a metal-support synergy interrupts the conventional reduction of nitroarenes into anilines and results in a novel tandem reaction route. In this work, the concept merging mild reduction and effective intermediate transformations is anticipated to develop more useful tandem reactions by rational catalyst design.

Herein, we report a AgF-mediated regio- and stereoselective acetoxyselenylation of terminal/internal alkynes from iodobenzene dicarboxylate [PhI(OCOR)₂] and diorganyl diselenides via multiple-site functionalization to afford β-selenyl enol esters in good yields. Alkynes derived from bioactive molecules, such as l(-)-borneol, l-menthol, and acyne oxalate, are also suitable for this transformation and afford the expected compounds.

The trifluoromethylacyl group (-COCF₃) is an important motif and widely studied in catalysis, medicinal chemistry, and materials science. Herein, a novel palladium-catalyzed selenofluoroalkylacylation of terminal alkynes with commercially available fluoroalkyl anhydride and diorganyl diselenides to afford β-seleno and aryl/alkyl disubstituted enones under mild conditions is disclosed. In addition, selenodifluoroacetylations and selenoperfluoroacetylations are also suitable for this reaction. Mechanistic studies reveal that this reaction proceeds via an oxidative radical-polar crossover process.

A metal and base-free effective synthetic approach for the direct amidation of esters via C(acyl)–O bond cleavage, using water as a green-solvent.

Due to the generation of multiple intermediates during the nitroarene reduction, precise interception of single one to develop tandem reactions involving both C−C and C−N bond formations still remains a significant challenge. Herein, the relay catalysis of a supported bifunctional cobalt catalyst with l ‐proline has been successfully applied to establish a bran‐new reductive annulation reaction of nitroarenes and formaldehyde, which enables direct and diverse construction of both symmetrical and unsymmetrical 1,3‐diaryl imidazolines. It proceeds with operational simplicity, good substrate and functionality compatibility, and excellent step and atom‐efficiency. Mechanistic studies reveal that the Co‐catalyst exhibits a synergistic effect on the formation of key N ‐hydroxy imine, and the l ‐proline subsequently facilitates the key C−C bond formation. The current work opens a door to develop useful transformations with nitroarenes by reduction‐interrupted strategy.

Due to the generation of multiple intermediates during the nitroarene reduction, precise interception of single one to develop tandem reactions involving both C−C and C−N bond formations still remains a significant challenge. Herein, the relay catalysis of a supported bifunctional cobalt catalyst with l ‐proline has been successfully applied to establish a bran‐new reductive annulation reaction of nitroarenes and formaldehyde, which enables direct and diverse construction of both symmetrical and unsymmetrical 1,3‐diaryl imidazolines. It proceeds with operational simplicity, good substrate and functionality compatibility, and excellent step and atom‐efficiency. Mechanistic studies reveal that the Co‐catalyst exhibits a synergistic effect on the formation of key N ‐hydroxy imine, and the l ‐proline subsequently facilitates the key C−C bond formation. The current work opens a door to develop useful transformations with nitroarenes by reduction‐interrupted strategy.