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Comprehensive Summary: Skipped dienes are of great importance but remain challenging to synthesize because of the presence of a sp3 hybrid carbon between the two alkenes. Herein, we have developed the first nickel‐catalyzed regio‐, (E)‐stereo‐ and linear‐selective ring‐opening/cross‐coupling reaction of vinylaziridines with organoboronic acids under mild conditions to construct various skipped aminodienes. The reaction exhibits wide functional‐group compatibility, and could be adapted for the introduction of skipped aminodiene functionality into bioactive molecules. In addition, the reaction could be carried out on a gram‐scale, delivering the ring‐opening products in high yields and with linear‐selectivity (90% yield, l : b >20 : 1). Furthermore, DFT calculations and mechanistic experiments provided detailed insights into the mechanism. [ABSTRACT FROM AUTHOR]

An iridium‐catalyzed remote site‐switchable hydroarylation of alkenes was reported, delivering the products functionalized at the subterminal methylene and terminal methyl positions on an alkyl chain controlled by two different ligands, respectively, in good yields and with good to excellent site‐selectivities. The catalytic system showed good functional group tolerance and a broad substrate scope, including unactivated and activated alkenes. More importantly, the regioconvergent transformations of mixtures of isomeric alkenes were also successfully realized. The results of the mechanistic studies demonstrate that the reaction undergoes a chain‐walking process to give an [Ar−Ir−H] complex of terminal alkene. The subsequent processes proceed through the modified Chalk–Harrod‐type mechanism via the migratory insertion of terminal alkene into the Ir−C bond followed by C−H reductive elimination to afford the hydrofunctionalization products site‐selectively. [ABSTRACT FROM AUTHOR]

The allylic alcohol structural motif is prevalent in many important molecules and valuable building blocks. The rearrangement reaction is one of the most important transformations, however there are only a few reports for the 1,3‐rearrangement of allylic alcohols. Herein, a 1,3‐rearrangement of allylic alcohols catalyzed by an Ir(III) dihydride complex is described. This reaction could provide the corresponding less accessible allylic alcohols regio‐ and stereoselectively from readily available E/Z mixtures of the substrates. Furthermore, a tandem alkene isomerization followed by 1,3‐rearrangement of homoallylic alcohols was also realized. In addition, this rearrangement reaction could be used to synthesize the natural product Navenone B. Mechanistic investigation indicated that the reaction pathway involved a π‐allyl‐Ir(V) intermediate and that the dihydride in the iridium catalyst acts as a hydrogen switch to modulate the valence of the iridium center. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Skipped dienes are of great importance but remain challenging to synthesize because of the presence of a sp3 hybrid carbon between the two alkenes. Herein, we have developed the first nickel‐catalyzed regio‐, (E)‐stereo‐ and linear‐selective ring‐opening/cross‐coupling reaction of vinylaziridines with organoboronic acids under mild conditions to construct various skipped aminodienes. The reaction exhibits wide functional‐group compatibility, and could be adapted for the introduction of skipped aminodiene functionality into bioactive molecules. In addition, the reaction could be carried out on a gram‐scale, delivering the ring‐opening products in high yields and with linear‐selectivity (90% yield, l : b >20 : 1). Furthermore, DFT calculations and mechanistic experiments provided detailed insights into the mechanism. [ABSTRACT FROM AUTHOR]