Nickel-catalyzed 1,4-rearrangement of an aryl Group in aryl N-benzylimidates via C–O and C–H bond cleavage

We report herein that nickel-catalyzed reaction of aryl imidates bearing an N-benzyl group results in 1,4-migration of an O-aryl group via the cleavage of C–O and C–H bonds. This protocol allows for the benzylic C–H bond arylation of benzylamine building blocks using phenols as an aryl source to form elaborate diarylmethylamine derivatives

Iridium/N-heterocyclic carbene-catalyzed C–H borylation of arenes by diisopropylaminoborane

Catalytic C–H borylation of arenes has been widely used in organic synthesis because it allows the introduction of a versatile boron functionality directly onto simple, unfunctionalized arenes. We report herein the use of diisopropylaminoborane as a boron source in C–H borylation of arenes. An iridium(I) complex with 1,3-dicyclohexylimidazol-2-ylidene is found to efficiently catalyze the borylation of arenes and heteroarenes. The resulting aminoborylated products can be converted to the corresponding boronic acid derivatives simply by treatment with suitable diols or diamines

Synthesis, Structure, and Reactivity of a Gallylene Derivative Bearing a Phenalenyl-Based Ligand

Phenalenyl-based N,N-bidentate ligand-stabilized monovalent gallium(I) 1 was synthesized and characterized. Compound 1 promotes the oxidative addition of I-I, Si-Cl, C-I, and S-S bonds and oxidative cyclization with various Pi-components. Compound 1 can also coordinate to a tungsten complex to form a gallium-tungsten bond

Synthesis of γ-Lactams from Acrylamides by Single-Carbon Atom Doping Annulation

A protocol for single-carbon atom doping annulation is reported, which enables the conversion of acrylamides into homologated γ-lactams through the cleavage of two σ-bonds and the formation of four new σ-bonds at the single carbon center. The key strategy is the use of N-heterocyclic carbenes as an atomic carbon equivalent by acting as carbon atom donors through the loss of a 1,2-diimine moiety. Experimental and computational studies reveal that the reaction proceeds through a spirocyclic intermediate, followed by the disassembly of the N-heterocyclic carbene skeleton via proton transfer.Fujimoto H., Nakayasu B., Tobisu M.. Synthesis of γ-Lactams from Acrylamides by Single-Carbon Atom Doping Annulation. Journal of the American Chemical Society 145, 19518 (2023); https://doi.org/10.1021/jacs.3c07052

Non-Stabilized Vinyl Anion Equivalents from Styrenes by N-Heterocyclic Carbene Catalysis and Its Use in Catalytic Nucleophilic Aromatic Substitution

A protocol for the catalytic nucleophilic activation of unactivated styrenes is reported, which enables the generation of a non-stabilized alkenyl anion equivalent as a transient intermediate. In the reaction, N-heterocyclic carbenes add across styrenes to generate ylide intermediates, which can then be used in intramolecular nucleophilic aromatic substitution reactions of aryl fluorides, chlorides, and methyl ethers. The method allows for straightforward access to complex polyaromatic compounds.Ito S., Fujimoto H., Tobisu M.. Non-Stabilized Vinyl Anion Equivalents from Styrenes by N-Heterocyclic Carbene Catalysis and Its Use in Catalytic Nucleophilic Aromatic Substitution. Journal of the American Chemical Society, 144, 15, 6714-6718, April 11, 2022. © 2022 American Chemical Society. https://doi.org/10.1021/jacs.2c02579

Synthesis of γ-Lactams from Acrylamides by Single-Carbon Atom Doping Annulation

Fujimoto H., Nakayasu B., Tobisu M.. Synthesis of γ-Lactams from Acrylamides by Single-Carbon Atom Doping Annulation. Journal of the American Chemical Society 145, 19518 (2023); https://doi.org/10.1021/jacs.3c07052.A protocol for single-carbon atom doping annulation is reported, which enables the conversion of acrylamides into homologated γ-lactams through the cleavage of two σ-bonds and the formation of four new σ-bonds at the single carbon center. The key strategy is the use of N-heterocyclic carbenes as an atomic carbon equivalent by acting as carbon atom donors through the loss of a 1,2-diimine moiety. Experimental and computational studies reveal that the reaction proceeds through a spirocyclic intermediate, followed by the disassembly of the N-heterocyclic carbene skeleton via proton transfer

Rhodium-catalyzed Decarbonylation of Acylsilanes

The rhodium-catalyzed decarbonylation of acylsilanes is reported. This reaction proceeds through the cleavage of a carbon–silicon bond in acylsilanes. When two different acylsilanes are reacted in one batch, crossover products are formed. These results indicate that two mechanisms are operating in this catalytic reaction.This is the peer reviewed version of the following article: Yoshida, T., Kodama, T., Tobisu, M., Asian J. Org. Chem. 2022, 11, e202200610 which has been published in final form at https://doi.org/10.1002/ajoc.202200610. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving. This article may not be enhanced, enriched or otherwise transformed into a derivative work, without express permission from Wiley or by statutory rights under applicable legislation. Copyright notices must not be removed, obscured or modified. The article must be linked to Wiley’s version of record on Wiley Online Library and any embedding, framing or otherwise making available the article or pages thereof by third parties from platforms, services and websites other than Wiley Online Library must be prohibited