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An "OFF/ON" electric current switching protocol was developed as a new strategy for one‐pot organic synthesis. Suzuki‐Miyaura coupling of 2‐bromopyridines with arylboronic acids in an electrochemical cell was performed without applying an electric current, and subsequently, the Pd‐catalyzed electrochemical C−H bromination was conducted using the already‐present Pd catalyst to obtain 2‐(2‐bromoaryl)pyridines as products. The one‐pot synthesis of bromoarenes can also be achieved without adding an external Br source in the second step. Furthermore, an OFF/ON/OFF two‐times switching protocol also realized the formation of an N‐containing teraryl derivative. [ABSTRACT FROM AUTHOR]

Palladium‐catalyzed remote arylative substitution was achieved for the reaction of arylboronic acids with alkenes possessing a distant acetoxy group to provide arylation products having an alkene moiety at the remote position. The use of β‐acetoxy elimination as a key step in the catalytic cycle allowed for regioselective formation of unstabilized alkenes after chain walking. This reaction was applicable to various arylboronic acids as well as alkene substrates. [ABSTRACT FROM AUTHOR]

Anti‐Markovnikov addition of anilines to aliphatic terminal alkynes proceeded using an 8‐quinolinolato rhodium/phosphine catalyst system. The use of a strong organic base, 1,1,3,3,–tetramethylguanidine, in the catalyst system enabled the formation of the aldimine products. Substrates with various functional groups including polar groups such as a phenolic hydroxy group are applicable to the hydroamination. [ABSTRACT FROM AUTHOR]

Transition‐metal‐catalyzed electrochemical C−H functionalizations have been extensively studied as atom‐ and step‐economical clean methods in organic synthesis. In this account, we described our efforts on the palladium‐catalyzed electrochemical C−H functionalizations, including C−H halogenations of arylpyridines and benzamide derivatives using HCl/HBr and I2 as a halogen source, a one‐pot process giving teraryls via the palladium‐catalyzed electrochemical C−H iodination and subsequent Suzuki‐Miyaura coupling, and an iodine‐mediated oxidative homo‐coupling reaction of arylpyridines. [ABSTRACT FROM AUTHOR]

We report a hydroaminative cyclization of enynes using phosphine‐quinolinolato rhodium catalysts. The hydroaminative cyclization of 2‐vinylphenylacetylene derivatives with secondary amines gives 2‐aminoindenes in good yields. The reaction is considered to proceed through carbon–carbon bond formation on a catalytically generated aminocarbene ligand. [ABSTRACT FROM AUTHOR]

We report here a method for in situ generation of various ruthenium carbonyl phosphine catalysts for arylation via cleavage of inert aromatic carbon–oxygen bonds. The use of catalyst systems consisting of [RuCl2(CO)(p‐cymene)], CsF, styrene, and phosphines enabled facile screening of phosphine ligands. Asymmetric C–O arylation was also achieved for atropo‐enantioselective biaryl synthesis using a chiral monodentate phosphine ligand. [ABSTRACT FROM AUTHOR]

Sequential formation of distant bonds in organic molecules was achieved for the palladium‐catalyzed hydrosilylation/cyclization of various 1,n‐dienes by chain walking of the metal catalyst. The reaction was applicable to various 1,n‐dienes, including a 1,13‐diene, to form a cyclopentane ring as well as a carbon–silicon bond at a remote site. The use of "nondissociative" chain walking provides a fascinating strategy in organic synthesis to functionalize distant parts of organic molecules, in a particular order, within a catalytic cycle by effectively moving the reactive center from a remote position. [ABSTRACT FROM AUTHOR]

Abstract: Palladium‐catalyzed ortho‐selective C−H iodination of N‐(8‐quinolinyl)benzamides proceeded using I2 under both electrochemical and non‐electrochemical conditions. The C−H iodination at 90 °C under base‐free conditions provided high yields of the iodination products. The use of anodic oxidation increased the efficiency of the iodination at sterically‐hindered positions. [ABSTRACT FROM AUTHOR]

Efficient, selective, transition-metal-catalyzed C−H functionalizations have been widely studied and are recognized as atom- and step-economical tools in organic synthesis. During the past two decades, a variety of catalytic reactions involving C−H bond cleavage have been developed. In this review, we briefly survey studies dealing with transition-metal-catalyzed efficient and selective C−H functionalization by electrochemical reactions. [ABSTRACT FROM AUTHOR]

An ortho‐selective C−H alkylation of aromatic ketones with N‐alkenylindoles proceeded in the presence of just a Fe(PMe3)4 catalyst. In addition, C−H indolylation products, which are considered to be formed via 1,4‐iron migration, were also observed as minor products. [ABSTRACT FROM AUTHOR]

Ruthenium-catalyzed selective monoalkenylation of ortho CO or CN bonds of aromatic ketones was achieved. The reaction allowed the direct comparison of the relative reactivities of the cleavage of different carbon-heteroatom bonds, thus suggesting an unconventional chemoselectivity, where smaller, more-electron-donating groups are more easily cleaved. Selective monofunctionalization of CO bonds in the presence of ortho CH bonds was also achieved. [ABSTRACT FROM AUTHOR]

Titelbild: Carbon-Carbon Bond Formation via Catalytically Generated Aminocarbene Complexes: Rhodium-Catalyzed Hydroaminative Cyclization of Enynes with Secondary Amines (Angew. Keywords: aminocarbene complexes; enynes; hydroaminative cyclization; rhodium; secondary amines EN aminocarbene complexes enynes hydroaminative cyclization rhodium secondary amines 11769 11769 1 07/08/20 20200713 NES 200713 B Heteroatom-stabilisierte b Übergangsmetall-Carbenkomplexe sind nützliche Bausteine für die organische Synthese, ihre katalytische Erzeugung aus Substraten mit gewöhnlichen funktionellen Gruppen ist jedoch eine Herausforderung. Aminocarbene complexes, enynes, hydroaminative cyclization, rhodium, secondary amines. [Extracted from the article]

Cover Feature: In Situ Generation of Ruthenium Carbonyl Phosphine Complexes as a Versatile Method for the Development of Enantioselective C-O Bond Arylation (Chem. Eur. J. 8/2020) The coordination of the acetyl group to the ruthenium center facilitates the Ar-OMe bond cleavage. Asymmetric synthesis, cleavage reactions, homogeneous catalysis, ruthenium, synthetic methods. [Extracted from the article]

Review: [73 refs. [ABSTRACT FROM AUTHOR]

The article presents chemical equations related to the article "Copper-Catalyzed Electrochemical Chlorination of 1,3-Dicarbonyl Compounds Using Hydrochloric Acid" by K. Tsuchida and others, published in the periodical "Asian Journal of Organic Chemistry" in 2013.

These two new catalytic reactions proceed via oxidative addition of the C-N-bonds, followed by a β-hydride elimination process from the ruthenium amide species. [ABSTRACT FROM AUTHOR]

The title reaction, affording cyclobutenes in high yields, is completely regioselective, and various combinations of terminal alkynes and acrylates can be used. [ABSTRACT FROM AUTHOR]

The use of chain walking provides a new method to functionalize unreactive C-H bonds. [ABSTRACT FROM AUTHOR]