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Abstract Alkynyl amides play crucial roles in organic synthesis in the production of bioactive compounds and valuable heterocycles. Despite numerous studies on their synthesis, challenges persist due to the necessity of harsh or hazardous conditions and the use of costly or unstable reagents. Herein, we present a one‐pot method for the synthesis of all three bonds of the alkyne under transition‐metal‐free conditions. An important feature of this chemistry is the use of readily available feedstock chemicals, such as methyl esters and acetamides. This approach offers efficient access to a wide range of aryl and alkyl alkynyl amides and demonstrates excellent tolerance towards various functional groups in a sustainable and cost‐effective manner. 

Abstract Carbosulfenylation of olefins represents an important class of reactions for the synthesis of structurally diverse organosulfur compounds. Previous studies typically yield 1,2‐regioselectivity. In the context of diversity‐oriented synthesis, accessing the regioreversed products is desirable, significantly broadening the scope of these reactions. In this study, we report a nickel‐catalyzed 2,1‐carbosulfenylation of trifluoromethyl‐ andgem‐difluoroalkenes, using free thiols and benzyl bromides as sulfur and carbon sources, respectively. The unusual regioselectivity observed is enabled by a “radical sorting” mechanism. The Ni catalyst activates benzyl bromide to generate a benzylic radical that undergoes hydrogen atom transfer (HAT) with the thiol to form a sulfur‐centered radical. The sulfur radical subsequently adds to the fluoroalkenes, resulting in an α‐fluoroalkyl C‐radical. This radical undergoes S_H2 with a Ni–CH₂Ar to form a C(sp³)─C(sp³) bond and quaternary center, ultimately producing valuable fluoroalkyl thioethers. Isotopic labeling experiments corroborate a hydrogen atom transfer (HAT) event within the working mechanism. 

Abstract Rh(I)‐catalyzed C8‐selective C−H alkenylation and arylation of 1,2,3,4‐tetrahydroquinolines with alkenyl and aryl carboxylic acids under microwave assistance have been realized. Using [Rh(CO)₂(acac)] as the catalyst and Piv₂O as the acid activator, 1,2,3,4‐tetrahydroquinolines undergo C8‐selective decarbonylative C−H alkenylation with a wide range of alkenyl and aryl carboxylic acids, affording the C8‐alkenylated or arylated 1,2,3,4‐tetrahydroquinolines. This method enables the synthesis of C8‐alkenylated 1,2,3,4‐tetrahydroquinolines that would otherwise be difficult to access by means of conventional C−H alkenylation protocols. Moreover, this catalytic system also works well in C8‐selective decarbonylative C−H arylation of 1,2,3,4‐tetrahydroquinolines with aryl carboxylic acids. The catalytic activity strongly depends on the choice of theN‐directing group, with the readily installable and removableN‐(2‐pyrimidyl) group being optimal. The catalytic pathway is elucidated by mechanistic experiments. 

Abstract BulkyN,N’‐bidentate ligands can furnish catalysts with enhanced catalytic activity compared to commercially available ligands. Straightforward methods to effectively synthesize a broad range of these ligands, however, are uncommon. In this work, a simple and efficient method is developed for the synthesis of bulkyN,N’‐bidentate ligands, including 2,2’‐bipyridines and enantioenriched pyridine‐oxazolines. The Pd/NIXANTPHOS catalyst system enabled synthesis of a series of bulky 2,2’‐bipyridine‐based ligands and (S)‐pyridine oxazoline‐based enantioenriched ligands with good to excellent yields. The ligands have been benchmarked in the aminofluorination of styrene. magnified image 

Abstract A base‐promoted net‐[3+2] cycloaddition of nitriles and 1‐arylpropynes for the synthesis of pyrroles is described. The developed method provides convenient access to various 2,5‐disubstituted or 2,4,5‐trisubstituted pyrroles in 40% to 96% yields (32 examples). Among methods for the synthesis of pyrroles, the protocol presented here stands out for its convenience and atom‐economy. 

Abstract The first Rh^I‐catalyzed, directed decarbonylative C2−H alkenylation of imidazoles with readily available alkenyl carboxylic acids is reported. The reaction proceeds in a highly regio‐ and stereoselective manner, providing efficient access to C2‐alkenylated imidazoles that are generally inaccessible by known C−H alkenylation methods. This transformation accommodates a wide range of alkenyl carboxylic acids, including challenging conjugated polyene carboxylic acids, and diversely decorated imidazoles with high functional group compatibility. The presence of a removable pyrimidine directing group and the use of a bidentate phosphine ligand are pivotal to the success of the catalytic reaction. This process is also suitable for benzimidazoles. Importantly, the scalability and diversification of the products highlight the potential of this protocol in practical applications. Detailed experimental and computational studies provide important insights into the underlying reaction mechanism. 

Abstract A simple one‐pot synthesis ofβ‐hydroxyallenamides is reported. This procedure entails chemo‐ and regioselective hydroboration of 3‐en‐1‐ynyl‐sulfonylamides with Cy₂BH followed by homoallenylation of aldehydes to yield β‐hydroxyallenamides (up to 94% yield and >20:1 dr). Controlled synthesis of up to three continuous stereochemical elements was realized. Density functional theory (DFT) calculations suggest a concerted Zimmerman‐Traxler chair‐like transition state. Initial results suggest that enantio‐ and diastereoselective synthesis of β‐hydroxyallenamides with optically active hydroboration reagents is viable. magnified image 

Abstract A Rh(I)‐catalyzed C6‐selective C−H arylation of 2‐pyridones with inexpensive, readily available, safe and structurally diverse aryl carboxylic acids with the aid of a pyridine directing group is developed. This decarbonylative arylation protocol features an easy‐to‐handle catalytic system, and is amenable to diversely substituted 2‐pyridones and aryl carboxylic acids. It allows access to a wide range of C6‐arylated 2‐pyridones, including those that are difficult to prepare using conventional C−H arylation processes. The method tolerates various electron‐neutral, electron‐rich and electron‐deficient functional groups, and affords the products in 41–91% yields. magnified image 

Abstract Cp*Rh(III)‐catalyzed chelation‐assisted direct C−H bond functionalization of 1‐(2‐pyridyl)‐2‐pyridones with internal alkynes that can be controlled to give three different products in good yields has been realized. Depending on the reaction conditions, solvents and additives, the reaction pathway can be switched between alkenylation, alkenylation/directing group migration and rollover annulation. These reaction manifolds allow divergent access to a variety of valuable C6‐alkenylated 1‐(2‐pyridyl)‐2‐pyridones, (Z)‐6‐(1,2‐diaryl‐2‐(pyridin‐2‐yl)vinyl)pyridin‐2(1H)‐ones and 10H‐pyrido[1,2‐a][1,8]naphthyridin‐10‐ones from the same starting materials. These protocols exhibit excellent regio‐ and stereoselectivity, broad substrate scope, and good tolerance of functional groups. A combination of experimental and computational approaches have been employed to uncover the key mechanistic features of these reactions. 

Abstract The selenenate anion (RSeO⁻) is introduced as an active organocatalyst for the dehydrohalogen coupling of benzyl halides to formtrans‐stilbenes. It is shown that RSeO⁻is a more reactive catalyst than the previously reported sulfur analogues (sulfenate anion, RSO⁻) and selenolate anions (RSe⁻) in the aforementioned reaction. This catalytic system was also applied to the benzylic‐chloromethyl‐coupling polymerization (BCCP) of a bis‐chloromethyl arene to form ppv (poly(p‐phenylene vinylene))‐type polymers with high yields, M_n(average molecular weight) up to 13,000 and Đ (dispersity) of 1.15. magnified image