We have developed a palladium‐catalyzed addition of a C−Si bond of acylsilanes across a range of unactivated allenes. The reaction proceeds with complete regioselectivity, in which a silyl group ...binds to the central carbon of the allene, allowing for the straightforward access to functionalized alkenylsilane derivatives.
Palladium‐catalyzed addition of a C−Si bond in acylsilanes across allenes is reported. The reaction proceeds with complete regioselectivity, in which a silyl group binds to the central carbon of the allene, allowing for the straightforward access to functionalized alkenylsilane derivatives.
Despite advances in methods for the decarbonylation of aldehydes, the decarbonylation of ketones has been met with limited success because this process requires the activation of two inert ...carbon–carbon bonds. All of the decarbonylation reactions of simple unstrained ketones reported to date require the addition of a stoichiometric rhodium complex. We report herein the nickel/N-heterocyclic carbene-mediated decarbonylation of simple diaryl ketones. This reaction shows unique acceleration effects based on the presence of both electron-donating and electron-withdrawing groups.
We report on a method for the synthesis of fluorinated dibenzophospholes using triarylphosphine via dearylative annulation with an aryne. This intermolecular annulation allows the preparation of a ...variety of fluorinated dibenzophospholes from simple building blocks. The key to the success of this dearylative annulation is the formation of a five-coordinated tetraarylfluorophosphorane. In this work, we successfully synthesized stable tetraarylfluorophosphorane, the structure of which was unambiguously determined by X-ray crystallography.
We report on the N-heterocyclic carbene (NHC)-catalyzed Truce–Smiles rearrangement of aniline derivatives, in which an unactivated C(aryl)–N bond is cleaved, leading to the formation of a new ...C(aryl)–C bond. The key to the success of this reaction is the utilization of a highly nucleophilic NHC, which enables the formation of a highly nucleophilic ylide intermediate that is generated from an α,β-unsaturated amide.
The iridium-mediated direct arylation of quinoline using an NHC ligand is reported. This reaction proceeds via cleavage of the carbon–carbon and carbon–nitrogen bonds of the NHC ligand and a ...carbon–hydrogen bond of quinoline.
Transition metal-catalyzed unimolecular fragment coupling (UFC) is defined as processes that forge new chemical bonds through the extrusion of molecules, such as CO and CO2, and the subsequent ...recombination of the remaining fragments. Herein, we report on a new UFC reaction that involves the palladium-catalyzed elimination of an isocyanate fragment from an amide, with the formation of carbon–carbon and carbon–heteroatom bonds. An organometallic intermediate that is relevant to the catalytic reaction was characterized by X-ray crystallography. This UFC reaction enables the late-stage transformation of an amide functionality, allowing amides to be used as a convertible directing or protecting group.
We report herein the phosphine-catalyzed 1,2-diacylation of alkynes using acyl fluorides and acylsilanes as acyl sources. The key to the success of the reaction is a formal oxidative addition–ligand ...metathesis–reductive elimination cycle based on phosphine redox catalysis, which allows for the installation of two different acyl groups into an alkyne in a regioselective manner.
The reductive cleavage of the C-O bonds of aryl ethers has great potential in organic synthesis. Although several catalysts that can promote the reductive cleavage of aryl ethers have been reported, ...all such systems require the use of an external reductant,
, hydrosilane or hydrogen. Here, we report the development of a new nickel-based catalytic system that can cleave the C-O bonds of ethers in the absence of an external reductant. The hydrogen atom required in this new reductive cleavage reaction is provided by the alkoxy group of the substrate, which serves as an internal reductant. The absence of an external reductant enables the unique chemoselectivity,
, the selective reduction of an alkoxy group over alkenes and ketones.
Catalytic amination: The title reaction demonstrates the use of aryl carboxylates as suitable electrophilic coupling substrates in catalytic amination reactions. N‐heterocyclic carbene ligands and ...NaOtBu promote the amination of aryl pivalates through the cleavage of normally unreactive aryl carbon–oxygen bonds (see scheme; cod=cyclooctadiene).
Seeing the sites: The Suzuki-Miyaura reaction of substrates containing multiple coupling sites has been performed in a directed manner through the reactivity modulation of the boron moiety (see ...scheme). Several other strategies are also discussed.
PDF