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A Pd‐catalyzed synthesis of 5‐iminopyrrolones from propiolamides was developed, which featured wide substrate scope and good yields. This efficient conversion involved a tandem hydrocyanation, E to Z isomerization of alkenes, and nitrile/amide cyclization. Control experiments show the intermediacy of β‐cyanation products, and the Z‐isomers was efficiently converted to the target products by Pd/L2 catalysis only after the cyanation reagent was completely consumed. [ABSTRACT FROM AUTHOR]

Daphenylline, a structurally unique triterpenoid Daphniphyllum alkaloid, has attracted considerable attention from the synthetic community since its isolation. Herein, we delineate an enantioselective total synthesis of (−)‐daphenylline, which is based on a gold‐catalyzed dearomatization reaction of β‐methoxynaphthalene. Other features include installation of the initial chiral stereocenter via an enantioselective rhodium‐catalyzed hydrogenation of an alkylidene‐indane derivative; construction of the other vital stereocenter by organocatalytic asymmetric Mukaiyama–Michael reaction of a structurally complex benzofused cyclohexanone; and a tandem reductive amination/amidation double cyclization reaction to assemble the distinctive azapolycyclic cage‐like architecture. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: The construction of acyclic quaternary carbon stereocenters, which are ubiquitous in many bioactive compounds, pharmaceuticals and natural products, has been a long persuit in synthetic organic chemistry. Among numerous methods, enantioselective nickel‐catalysis has attracted incremental attention in recent years. This review summarizes the recent development in the asymmetric strategies, research progress, mechanistic investigations for the generation of acyclic quaternary carbon stereocenters via enantioselective nickel catalysis. Key Scientists: In 2006, the Zhou group and RajanBabu group realized the nickel‐catalyzed enantioselective hydrovinylation of α‐substituted styrenes and ethylene to construct acyclic quaternary carbon stereocenters (QCSs) by using spiro‐ and binaphthyl phosphoramidite ligands, respectively. In 2016, Watson developed a nickel‐catalyzed Suzuki‐Miyaura arylation to generate acyclic QCSs via chirality transfer reaction. In 2017, the Feng and the Fu group developed nickel‐catalyzed enantioselective conjugated/Michael additions to build acyclic QCSs, respectively. In 2020, the Fang group made the first success in the construction of QCSs by nickel‐catalyzed hydrocyanation of alkenes and allenes. In 2021, Gregory C. Fu and co‐workers disclosed a nickel‐catalyzed enantioselective α‐functionalization of carbonyl compounds that could form acyclic QCSs. At the same time, the Shi group constructed chiral acyclic QCSs via nickel‐catalyzed functionalization of alkenes. In 2023, Kleij and co‐workers applied a new strategy for Ni‐catalyzed regio‐ and enantioselective homoallylic coupling to construct acyclic QCSs. In the same year, Tao and co‐workers demonstrated a novel strategy that is dinickel‐catalyzed enantioselective α‐alkylation of carbonyl compounds with alkyl iodides. [ABSTRACT FROM AUTHOR]

Metal‐hydride‐catalyzed migratory functionalization of alkenes witnessed extensive development in the past few years. However, the asymmetric version of this reaction has remained largely underdeveloped owing to the difficulty in simultaneous control of both regio‐ and stereoselectivity. In addition, exploring the wider alkene substrate scope to enable more synthetically valuable applications represents another challenge in this field. In this context, a nickel‐catalyzed asymmetric hydrocyanation of internal alkenes involving a chain‐walking process is demonstrated. The reaction exhibits excellent regio‐ and enantioselectivity, proceeds under mild reaction conditions, and delivers benzylic nitriles in high yields. Even α,ω‐diaryl internal alkenes, which are known to be one of the most challenging substrates of this type, could be successfully converted to the desired products with good regio‐ and stereoselectivity by modifying the electronic and steric effects. Theoretical calculations suggest that the η3‐benzyl coordination mode and the aryl substituent (3,5‐(OMe)2C6H3) on the diphosphite ligand are both key factors in regulating regio‐ and enantioselectivity. [ABSTRACT FROM AUTHOR]

N‐Heterocyclic amines have been known as an important class of nitrogen‐containing molecules with a wide range of applications. Described here is a mild and efficient electrochemical desulfurizative amination of readily accessible heteroaromatic thiols without necessity of metal catalyst. The key to success for this reaction is the in‐situ generation of a hypervalent iodine reagent as an organocatalyst from iodoarene by anodic oxidation. This mild desulfurizative amination presents ample substrate scope and good functional group tolerance without the use of extra stoichiometric chemical oxidants. As only electrons serve as the oxidation reagents, this method offers a straightforward and sustainable manner towards versatile N‐heterocyclic amines, including late‐stage functionalization of pharmaceutically relevant molecules. [ABSTRACT FROM AUTHOR]

We herein describe a palladium‐catalyzed hydrocyanation of propiolamides for the stereodivergent synthesis of trisubstituted acrylonitriles. This synthetic method tolerated various primary, secondary and tertiary propiolamides. The cautious selection of a suitable ligand is essential to the success of this stereodivergent process. Control experiments indicate the intermediacy of E‐acrylonitriles, which lead to Z‐acrylonitriles via isomerization. The density functional theory calculations suggests that the bidentate ligand L2 enables a feasible cyclometallation/isomerization pathway for the E to Z isomerization, while the monodentate ligand L1 inhibits the isomerization, leading to divergent stereoselectivity. The usefulness of this method can be demonstrated by the readily derivatization of products to give various E‐ and Z‐trisubstituted alkenes. In addition, the E‐ and Z‐acrylonitrile products have also been successfully employed in cycloaddition reactions. [ABSTRACT FROM AUTHOR]

Enantioselective auto‐tandem catalysis represents a challenging yet highlight attractive topic in the field of asymmetric catalysis. In this context, we describe a dual catalytic cycle that merges allylic cyanation and asymmetric hydrocyanation. The one‐pot conversion of a broad array of allylic alcohols into their corresponding 1,3‐dinitriles proceeds in good yield with high enantioselectivity. The products are densely functionalized and can be easily transformed to chiral diamines, dinitriles, diesters, and piperidines. Mechanistic studies clearly support a novel sequential cyanation/hydrocyanation pathway. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: The construction of acyclic quaternary carbon stereocenters, which are ubiquitous in many bioactive compounds, pharmaceuticals and natural products, has been a long persuit in synthetic organic chemistry. Among numerous methods, enantioselective nickel‐catalysis has attracted incremental attention in recent years. This review summarizes the recent development in the asymmetric strategies, research progress, mechanistic investigations for the generation of acyclic quaternary carbon stereocenters via enantioselective nickel catalysis. Key Scientists: In 2006, the Zhou group and RajanBabu group realized the nickel‐catalyzed enantioselective hydrovinylation of α‐substituted styrenes and ethylene to construct acyclic quaternary carbon stereocenters (QCSs) by using spiro‐ and binaphthyl phosphoramidite ligands, respectively. In 2016, Watson developed a nickel‐catalyzed Suzuki‐Miyaura arylation to generate acyclic QCSs via chirality transfer reaction. In 2017, the Feng and the Fu group developed nickel‐catalyzed enantioselective conjugated/Michael additions to build acyclic QCSs, respectively. In 2020, the Fang group made the first success in the construction of QCSs by nickel‐catalyzed hydrocyanation of alkenes and allenes. In 2021, Gregory C. Fu and co‐workers disclosed a nickel‐catalyzed enantioselective α‐functionalization of carbonyl compounds that could form acyclic QCSs. At the same time, the Shi group constructed chiral acyclic QCSs via nickel‐catalyzed functionalization of alkenes. In 2023, Kleij and co‐workers applied a new strategy for Ni‐catalyzed regio‐ and enantioselective homoallylic coupling to construct acyclic QCSs. In the same year, Tao and co‐workers demonstrated a novel strategy that is dinickel‐catalyzed enantioselective α‐alkylation of carbonyl compounds with alkyl iodides. [ABSTRACT FROM AUTHOR]

A novel and efficient method for the synthesis of O -allenes and N -allenes via isomerization of terminal alkynes catalyzed by cesium hydroxide monohydrate is described. The advantages of this method include: mild reaction conditions, high yields and wide tolerance toward functional groups. The protocol provides an efficient route to O -allenes and N -allenes, which are important intermediates in organic synthetic chemistry. [ABSTRACT FROM AUTHOR]