Browse
Submit Data
Databases
API
Help

Dataset Information

43 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

A palladium-catalyzed C-H functionalization route to ketones via the oxidative coupling of arenes with carbon monoxide.

ABSTRACT: We describe the development of a new palladium-catalyzed method to generate ketones via the oxidative coupling of two arenes and CO. This transformation is catalyzed by simple palladium salts, and is postulated to proceed via the conversion of arenes into high energy aroyl triflate electrophiles. Exploiting the latter can also allow the synthesis of unsymmetrical ketones from two different arenes.

SUBMITTER: Levesque TM

PROVIDER: S-EPMC8157493 | biostudies-literature | 2020 Feb

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

A palladium-catalyzed C-H functionalization route to ketones via the oxidative coupling of arenes with carbon monoxide.

Levesque Taleah M TM Kinney R Garrison RG Arndtsen Bruce A BA

Chemical science 20200220 11

We describe the development of a new palladium-catalyzed method to generate ketones via the oxidative coupling of two arenes and CO. This transformation is catalyzed by simple palladium salts, and is postulated to proceed via the conversion of arenes into high energy aroyl triflate electrophiles. Exploiting the latter can also allow the synthesis of unsymmetrical ketones from two different arenes. ...[more]

PMID: 34122815

Similar Datasets

Palladium catalyzed carbonylative generation of potent, pyridine-based acylating electrophiles for the functionalization of arenes to ketones.

Project description:We describe here the design of a palladium catalyzed route to generate aryl ketones via the carbonylative coupling of (hetero)arenes and aryl- or vinyl-triflates. In this, the use of the large bite angle Xantphos ligand on palladium provides a unique avenue to balance the activation of the relatively strong C(sp2)-OTf bond with the ultimate elimination of a new class of potent Friedel-Crafts acylating agent: N-acyl pyridinium salts. The latter can be exploited to modulate reactivity and selectivity in carbonylative arene functionalization chemistry, and allow the efficient synthesis of ketones with a diverse array of (hetero)arenes.

| S-EPMC8163404 | biostudies-literature

Palladium-catalyzed oxidative cross-coupling for the synthesis of α-amino ketones.

Project description:A novel oxidative cross-coupling reaction for the synthesis of α-aryl α-amino ketones in the presence of palladium catalysts using T+BF4 - as an oxidant has been developed. This transformation was achieved by direct C-H oxidation of α-aminocarbonyl compounds and arylation. The mild reaction has a broad reaction scope and gives desired α-aryl α-amino ketones in moderate to excellent yields.

| S-EPMC9072988 | biostudies-literature

Toward Green Acylation of (Hetero)arenes: Palladium-Catalyzed Carbonylation of Olefins to Ketones.

Project description:Green Friedel-Crafts acylation reactions belong to the most desired transformations in organic chemistry. The resulting ketones constitute important intermediates, building blocks, and functional molecules in organic synthesis as well as for the chemical industry. Over the past 60 years, advances in this topic have focused on how to make this reaction more economically and environmentally friendly by using green acylating conditions, such as stoichiometric acylations and catalytic homogeneous and heterogeneous acylations. However, currently well-established methodologies for their synthesis either produce significant amounts of waste or proceed under harsh conditions, limiting applications. Here, we present a new protocol for the straightforward and selective introduction of acyl groups into (hetero)arenes without directing groups by using available olefins with inexpensive CO. In the presence of commercial palladium catalysts, inter- and intramolecular carbonylative C-H functionalizations take place with good regio- and chemoselectivity. Compared to classical Friedel-Crafts chemistry, this novel methodology proceeds under mild reaction conditions. The general applicability of this methodology is demonstrated by the direct carbonylation of industrial feedstocks (ethylene and diisobutene) as well as of natural products (eugenol and safrole). Furthermore, synthetic applications to drug molecules are showcased.

| S-EPMC5785770 | biostudies-literature

S,O-Ligand-Promoted Palladium-Catalyzed C-H Functionalization Reactions of Nondirected Arenes.

Project description:Pd(II)-catalyzed C-H functionalization of nondirected arenes has been realized using an inexpensive and easily accessible type of bidentate S,O-ligand. The catalytic system shows high efficiency in the C-H olefination reaction of electron-rich and electron-poor arenes. This methodology is operationally simple, scalable, and can be used in late-stage functionalization of complex molecules. The broad applicability of this catalyst has been showcased in other transformations such as Pd(II)-catalyzed C-H acetoxylation and allylation reactions.

| S-EPMC5617328 | biostudies-literature

Palladium-Catalyzed Oxidative Allene-Allene Cross-Coupling.

Project description:Direct cross-coupling reactions between two similar unactivated partners are challenging but constitute a powerful strategy for the creation of new carbon-carbon bonds in organic synthesis. [4]Dendralenes are a class of acyclic branched conjugated oligoenes with great synthetic potential for the rapid generation of structural complexity, yet the chemistry of [4]dendralenes remains an unexplored field due to their limited accessibility. Herein, we report a highly selective palladium-catalyzed oxidative cross-coupling of two allenes with the presence of a directing olefin in one of the allenes, enabling the facile synthesis of a broad range of functionalized [4]dendralenes in a convergent modular manner. Specifically, the selective allenic C-H activation of an allene with an allyl substituent as the assisting group gives rise to a vinylpalladium intermediate, which reacts with a less substituted allene in a carbopalladation, followed by a β-hydride elimination. The reaction sequence leads to a new C(sp2)-C(sp2) bond between two diene units. Remarkably, this protocol provides an unconventional strategy for the site-selective and stereoselective construction of C(vinyl)-C(vinyl) bonds without using any halogenated and organometallics olefin precursors. Furthermore, the practical transformations of the synthesized [4]dendralenes and late-stage modifications of biorelevant molecules demonstrate their potential in the total synthesis of natural products and drug discovery.

| S-EPMC11803718 | biostudies-literature

Palladium-catalyzed acetylation of arenes.

Project description:A simple method for the preparation of aryl methyl ketones is reported. The transformation involves the Pd-catalyzed coupling of an acyl anion equivalent, acetyltrimethylsilane, with aryl bromides to afford the corresponding acetylated arenes in synthetically useful yields. The methodology is tolerant of heterocycles and provides a new method for arene functionalization.

| S-EPMC3937967 | biostudies-literature

Double heteroatom functionalization of arenes using benzyne three-component coupling.

Project description:Arynes participate in three-component coupling reactions with N, S, P, and Se functionalities to yield 1,2-heteroatom-difunctionalized arenes. Using 2-iodophenyl arylsulfonates as benzyne precursors, we could effectively add magnesiated S-, Se-, and N-nucleophilic components to the strained triple bond. In the same pot, addition of electrophilic N, S, or P reagents and a copper(I) catalyst trapped the intermediate aryl Grignard to produce a variety of 1,2-difunctionalized arenes.

| S-EPMC4832838 | biostudies-other

Rhodium(III)-catalyzed oxidative carbonylation of benzamides with carbon monoxide.

Project description:An efficient strategy for the oxidative carbonylation of aromatic amides via C-H/N-H activation to form phthalimides using an Rh(III) catalyst has been developed. The reaction shows a preference for C-H bonds of electron-rich aromatic amides and tolerates a variety of functional groups.

| S-EPMC3423973 | biostudies-literature

Combined oxypalladation/C-H functionalization: palladium(II)-catalyzed intramolecular oxidative oxyarylation of hydroxyalkenes.

Project description: Not available

| S-EPMC3347770 | biostudies-literature

Palladium catalyzed radical relay for the oxidative cross-coupling of quinolines.

Project description:Traditional approaches for transition-metal catalyzed oxidative cross-coupling reactions rely on sp2-hybridized starting materials, such as aryl halides, and more specifically, homogeneous catalysts. We report a heterogeneous Pd-catalyzed radical relay method for the conversion of a heteroarene C(sp3)-H bond into ethers. Pd nanoparticles are supported on an ordered mesoporous composite which, when compared with microporous activated carbons, greatly increases the Pd d charge because of their strong interaction with N-doped anatase nanocrystals. Mechanistic studies provide evidence that electron-deficient Pd with Pd-O/N coordinations efficiently catalyzes the radical relay reaction to release diffusible methoxyl radicals, and highlight the difference between this surface reaction and C-H oxidation mediated by homogeneous catalysts that operate with cyclopalladated intermediates. The reactions proceed efficiently with a turn-over frequency of 84 h-1 and high selectivity toward ethers of >99%. Negligible Pd leaching and activity loss are observed after 7 catalytic runs.

| S-EPMC9296488 | biostudies-literature