The modulation of selectivity of highly reactive carbon radical cross-coupling for the construction of C-C bonds represents a challenging task in organic chemistry. N-Heterocyclic carbenes (NHCs) catalyzed radical transformations opened...

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Rh(III)-catalyzed C-H activation and annulation of 1-benzoylpyrrolidine with propargyl alcohols has been achieved for an efficient synthesis of (4-benzylidene)isochroman-1-one. Highly enantioenriched products were obtained starting from optically pure propargyl alcohols.

Axially chiral aldehydes have received increasing attention in enantioselective catalysis. However, only very few catalytic methods have been developed to construct structurally diverse axially chiral aldehydes. We herein describe an NHC-catalyzed atroposelective esterification of biaryl dialdehydes as a general and practical strategy for the construction of axially chiral aldehydes. Mechanistic studies indicate that coupling proceeds through a novel combination of NHC-catalyzed desymmetrization of the dialdehydes and kinetic resolution. This protocol features excellent enantioselectivity, mild conditions, good functional-group tolerance, and applicability to late-stage functionalization and provides a modular platform for the synthesis of axially chiral aldehydes and their derivatives.

By using N-fluorobenzenesulfonimide as both the oxidant and the amination reagent, we have realized the first example of the intermolecular chalcogenative amination of alkynes, which grants facile, highly regio- and stereoselective access to chalcogenated enamides. The reaction features mild conditions, high yields and selectivities, remarkably broad substrate scope, and excellent functional group tolerance. Mechanistic studies indicate the in situ generated chalcogen imidates to be the actual reactive species, which in turn, has clarified the mechanism of related transformations. These reactions represent significant additions to the development of the highly selective amino bisfunctionalization of alkynes.

4-Acyl-1-sulfonyltriazoles act as versatile carbene reagents in Cp*Rh(III)-catalyzed ortho-selective coupling with arenes via C-H activation. The coupling led to olefination with possible cyclization, depending on the nature of the arene.

A novel hydroamination of aryl C-H bonds has been accomplished using N-Boc-hydroxyamine via synergistic combination of rhodium and copper catalysis. The merger of two robust catalytic systems has allowed for the development of a mild and sustainable protocol for the direct formation of benzo[c]isoxazol-3(1H)-ones.

Supportinginformation and the ORCID identification number(s) for the author(s) of this article can be found under: https://doi.