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This article explores the use of chromium-promoted dearomative hydrocyanoalkylation in organic synthesis. The authors emphasize the versatility of the cyano group and the potential for using simple alkylnitriles as cost-effective sources. They acknowledge the challenges of dearomatization reactions and the limited range of current methods. The authors present their own research on the efficient dearomative hydrocyanoalkylation of chromium-bound (hetero)arenes using simple alkylnitriles, with a focus on optimizing reaction conditions. This research has the potential to expand the scope of dearomative hydrocyanoalkylation reactions and provide new synthetic building blocks. Additionally, the article discusses a new method for synthesizing complex cyclohexadiene compounds using a chromium-mediated reaction. The authors demonstrate the broad applicability of the reaction by successfully synthesizing various arenes and heteroarenes with different substituents and functional groups. They also extend the methodology to include the synthesis of deuterated cyclohexadienes and the transformation of the products into more structurally complex compounds. The authors highlight the potential applications of this method in the synthesis of bioactive natural products and alkaloids. [Extracted from the article]

Herein, a general strategy for chemo‐ and regioselective 1,2‐reduction of chromium‐bound arenes was developed, thus providing rapid access to 1,3‐cyclohexadienes. Selective arene activation via π‐complexation along with the use of mild hydride Ph3SiH can overcome the inherently low reactivity of arene π‐bonds while tolerating various reduction‐sensitive functional groups. Its versatility further enables a regiodivergent deuteration. Using different sequences of (non)deuterated hydride and acid reagents, the deuterated positions as well as the degrees of deuterium incorporation can be controlled precisely, which leads to a large and previously inaccessible chemical space for 1,3‐cyclohexadiene isotopologues. A reasonable mechanism was proposed based on intermediate capture and control experiments. The synthetic value of this selective 1,2‐reduction was demonstrated in the formal total synthesis of (±)‐galanthamine and (±)‐lycoramine. [ABSTRACT FROM AUTHOR]

Herein, a general strategy for chemo‐ and regioselective 1,2‐reduction of chromium‐bound arenes was developed, thus providing rapid access to 1,3‐cyclohexadienes. Selective arene activation via π‐complexation along with the use of mild hydride Ph3SiH can overcome the inherently low reactivity of arene π‐bonds while tolerating various reduction‐sensitive functional groups. Its versatility further enables a regiodivergent deuteration. Using different sequences of (non)deuterated hydride and acid reagents, the deuterated positions as well as the degrees of deuterium incorporation can be controlled precisely, which leads to a large and previously inaccessible chemical space for 1,3‐cyclohexadiene isotopologues. A reasonable mechanism was proposed based on intermediate capture and control experiments. The synthetic value of this selective 1,2‐reduction was demonstrated in the formal total synthesis of (±)‐galanthamine and (±)‐lycoramine. [ABSTRACT FROM AUTHOR]

Inside Cover: Chemoselective 1,2-Reduction and Regiodivergent Deuteration of Chromium-Bound Arenes (Angew. Keywords: 1,3-Cyclohexadiene; Arene Reduction; Chromium; Deuterium; Reductive Deuteration EN 1,3-Cyclohexadiene Arene Reduction Chromium Deuterium Reductive Deuteration 1 1 1 04/19/23 20230424 NES 230424 B Arene 1,2-reduction b and regiodivergent deuteration via SP 6 sp -coordination have been developed by Wei Li and co-workers in their Research Article (e202218961). 1,3-Cyclohexadiene, Arene Reduction, Chromium, Deuterium, Reductive Deuteration. [Extracted from the article]

1,3-Cyclohexadiene, Arene Reduction, Chromium, Deuterium, Reductive Deuteration Keywords: 1,3-Cyclohexadiene; Arene Reduction; Chromium; Deuterium; Reductive Deuteration EN 1,3-Cyclohexadiene Arene Reduction Chromium Deuterium Reductive Deuteration 1 1 1 04/18/23 20230424 NES 230424 B Arene 1,2-reduction b and regiodivergent deuteration via SP 6 sp -coordination have been developed by Wei Li and co-workers in their Research Article (e202218961). A diverse set of 1,3-cyclohexadiene isotopologues were readily synthesized by precisely controlling the deuterated positions as well as the degrees of deuterium incorporation. [Extracted from the article]

Amides are ubiquitous in physical and life sciences. Given the significant abundance of arenes, dearomative aminocarbonylation of arenes would lead to a large and underexplored chemical space for amide discovery. However, such reactions are challenging due to the high degree of resonance stabilization and selectivity issues. Herein, we disclose an unprecedented dearomative trifluoromethylative aminocarbonylation of arenes via bifunctional coordination to chromium, providing a modular platform for the construction of amides possessing trifluoromethyl (CF3) groups and three‐dimensional rings. Its versatility further enabled a switchable difluoromethylation or trifluoromethylation aminocarbonylation of arene C−H bonds. A possible mechanism was proposed based on control experiments. Finally, the synthetic utility was well demonstrated by diverse applications in the total synthesis of CF3‐functionalized amide‐type drugs, including praziquantel, nateglinide, maraviroc and alloyohimbane. [ABSTRACT FROM AUTHOR]

Amides are ubiquitous in physical and life sciences. Given the significant abundance of arenes, dearomative aminocarbonylation of arenes would lead to a large and underexplored chemical space for amide discovery. However, such reactions are challenging due to the high degree of resonance stabilization and selectivity issues. Herein, we disclose an unprecedented dearomative trifluoromethylative aminocarbonylation of arenes via bifunctional coordination to chromium, providing a modular platform for the construction of amides possessing trifluoromethyl (CF3) groups and three‐dimensional rings. Its versatility further enabled a switchable difluoromethylation or trifluoromethylation aminocarbonylation of arene C−H bonds. A possible mechanism was proposed based on control experiments. Finally, the synthetic utility was well demonstrated by diverse applications in the total synthesis of CF3‐functionalized amide‐type drugs, including praziquantel, nateglinide, maraviroc and alloyohimbane. [ABSTRACT FROM AUTHOR]

The incorporation of the privileged amino functionality is of paramount importance in organic synthesis. In contrast to the well‐developed amination methods for alkenes, the dearomative amination of arenes is largely underexplored due to the inherently inert reactivity of arene π‐bonds and selectivity challenges. Herein, we report an intermolecular dearomative aminofunctionalization via direct nucleophilic addition of simple amines to chromium‐bound arenes. This multicomponent 1,2‐amination/carbonylation reaction enables rapid access to complicated alicyclic compounds containing amino and amide functionalities from benzene derivatives under CO‐gas‐free conditions, which also represents the first application of nitrogen‐based nucleophiles in η6‐coordination‐induced arene dearomatizations. [ABSTRACT FROM AUTHOR]