Catalyst-controlled divergent addition reactions of enoldiazoacetamides with nitrones have been developed. By using copper(I) tetrafluoroborate/bisoxazoline complex as the catalyst, a [3+3]-cycloaddition reaction was achieved with excellent yield and enantioselectivity under exceptionally mild conditions, which represents the first highly enantioselective base-metal-catalyzed vinylcarbene transformation. When the catalyst was changed to copper(I) triflate, Mannich addition products were formed in high yields with near exclusivity under otherwise identical conditions.

Over the past decade, vinyldiazo compounds have provided mild, efficient, and highly selective methods for the construction of heterocycles and carbocycles. Dinitrogen extrusion with suitable catalysts provides the carbon framework for [3+n] cycloaddition with a large variety of dipolarophiles. This minireview, covering the latest achievements in the field of metal‐catalyzed cyclization reactions with vinyldiazo reagents, focuses on reagent‐ or catalyst‐dependent chemodivergence: different vinyldiazo reagents or metal catalysts direct reactions to different cyclization pathways that give different reaction outcomes. Accordingly, metal‐catalyzed cyclization reactions of vinyldiazo compounds with nitrosoarenes, nitrones, indoles, and other diazo compounds are chosen to showcase the controllable versatility of the combination of vinyldiazo reagents and metal catalysts.

Ap alladium-catalyzed coupling between aryl halides and monocyclopropanated pyrroles or furans has been developed, leading to valuable six-membered N-and Oheterocycles.A st he key step,as elective cleavage of the nonactivated endocyclic CÀCb ond of the 2-heterobicyclo-[3.1.0]hexane framework is achieved. The developed method offers access to highly functionalized piperidines,p yridines, and pyrans that are challenging to access by traditional methods.Supportinginformation and the ORCID identification number(s) for the author(s) of this article can be found under: https://doi.

A dirhodium(II)-catalyzed annulation reaction between two structurally different diazocarbonyl compounds furnishes the donor–acceptor cyclopropane-fused benzoxa[3.2.1]octane scaffold with excellent chemo-, regio-, and diastereoselectivity under exceptionally mild conditions. The composite transformation occurs by [3+2]-cycloaddition between donor–acceptor cyclopropenes generated from enoldiazoacetamides and carbonyl ylides formed from intramolecular carbene–carbonyl cyclization in one pot with one catalyst. The annulation products can be readily transformed into benzoxa[3.3.1]nonane and hexahydronaphthofuran derivatives with exact stereocontrol. This method allows the efficient construction of three fused and bridged ring systems, all of which are important skeletons of numerous biologically active natural products.

Pd- or Ni-catalyzed C-H arylation of 4-nitroimidazole derivatives directed by a manipulable nitro group was developed. The reaction tolerates a wide range of substituted aryl halides and 4-nitroimidazoles. The experiments indicated that the nitro group has influence on regioselectivity of the reaction. In addition, we have shown that the efficiency of the Suzuki-Miyaura cross-coupling reaction of nitroimidazoles is slightly lower in comparison to the direct C-H arylation. The exploration of the chemical potential of the nitro group and a putative reaction mechanism are discussed.