Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Nickel-Catalyzed Activation of Acyl C-O Bonds of Methyl Esters.

ABSTRACT: We report the first catalytic method for activating the acyl C-O bonds of methyl esters through an oxidative-addition process. The oxidative-addition adducts, formed using nickel catalysis, undergo in?situ trapping to provide anilide products. DFT calculations are used to support the proposed reaction mechanism, to understand why decarbonylation does not occur competitively, and to elucidate the beneficial role of the substrate structure and the Al(OtBu)3 additive on the kinetics and thermodynamics of the reaction.

SUBMITTER: Hie L

PROVIDER: S-EPMC4821830 | biostudies-literature | 2016 Feb

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

Nickel-Catalyzed Activation of Acyl C-O Bonds of Methyl Esters.

Hie Liana L Fine Nathel Noah F NF Hong Xin X Yang Yun-Fang YF Houk Kendall N KN Garg Neil K NK

Angewandte Chemie (International ed. in English) 20160125 8

We report the first catalytic method for activating the acyl C-O bonds of methyl esters through an oxidative-addition process. The oxidative-addition adducts, formed using nickel catalysis, undergo in situ trapping to provide anilide products. DFT calculations are used to support the proposed reaction mechanism, to understand why decarbonylation does not occur competitively, and to elucidate the beneficial role of the substrate structure and the Al(OtBu)3 additive on the kinetics and thermodynam ...[more]

PMID: 26804615

Similar Datasets

Conversion of amides to esters by the nickel-catalysed activation of amide C-N bonds.

Project description:Amides are common functional groups that have been studied for more than a century. They are the key building blocks of proteins and are present in a broad range of other natural and synthetic compounds. Amides are known to be poor electrophiles, which is typically attributed to the resonance stability of the amide bond. Although amides can readily be cleaved by enzymes such as proteases, it is difficult to selectively break the carbon-nitrogen bond of an amide using synthetic chemistry. Here we demonstrate that amide carbon-nitrogen bonds can be activated and cleaved using nickel catalysts. We use this methodology to convert amides to esters, which is a challenging and underdeveloped transformation. The reaction methodology proceeds under exceptionally mild reaction conditions, and avoids the use of a large excess of an alcohol nucleophile. Density functional theory calculations provide insight into the thermodynamics and catalytic cycle of the amide-to-ester transformation. Our results provide a way to harness amide functional groups as synthetic building blocks and are expected to lead to the further use of amides in the construction of carbon-heteroatom or carbon-carbon bonds using non-precious-metal catalysis.

| S-EPMC4529356 | biostudies-literature

Photochemical Asymmetric Nickel-Catalyzed Acyl Cross-Coupling.

Project description:Photochemical enantioselective nickel-catalyzed cross-coupling reactions are difficult to implement. We report a visible-light-mediated strategy that successfully couples symmetrical anhydrides and 4-alkyl dihydropyridines (DHPs) to afford enantioenriched ?-substituted ketones under mild conditions. The chemistry does not require exogenous photocatalysts. It is triggered by the direct excitation of DHPs, which act as a radical source and as a reductant, facilitating the turnover of the chiral catalytic nickel complex.

| S-EPMC6900114 | biostudies-literature

Nickel-Catalyzed Decarbonylative Amination of Carboxylic Acid Esters.

Project description:The reaction of carboxylic acid derivatives with amines to form amide bonds has been the most widely used transformation in organic synthesis over the past century. Its utility is driven by the broad availability of the starting materials as well as the kinetic and thermodynamic driving force for amide bond formation. As such, the invention of new reactions between carboxylic acid derivatives and amines that strategically deviate from amide bond formation remains both a challenge and an opportunity for synthetic chemists. This report describes the development of a nickel-catalyzed decarbonylative reaction that couples (hetero)aromatic esters with a broad scope of amines to form (hetero)aryl amine products. The successful realization of this transformation was predicated on strategic design of the cross-coupling partners (phenol esters and silyl amines) to preclude conventional reactivity that forms inert amide byproducts.

| S-EPMC7533108 | biostudies-literature

Nickel Catalyzed Vinylidene Insertions into O-H Bonds.

Project description:A (pybox)Ni catalyst (pybox = pyridine-bis(oxazoline)) promotes the reductive cyclization of β-hydroxy 1,1-dichloroalkenes to form 2,3-dihydrofurans. The substrates for this reaction are conveniently prepared by an aldol addition followed by one-carbon homologation. Chiral substrates are accessible in highly enantioenriched form, allowing for the synthesis of stereochemically complex 2,3,4-trisubstituted products. Mechanistic studies support a vinylidene O-H insertion pathway rather than C-O cross-coupling followed by reductive dechlorination.

| S-EPMC8115312 | biostudies-literature

Nickel-catalyzed insertions of vinylidenes into Si-H bonds.

Project description:A nickel-catalyzed reductive cyclization of 1,1-dichloroalkenyl silanes is reported. The products of this reaction are unsaturated five- or six-membered silacycles. Intermolecular variants are also described, providing access to trisubstituted vinyl silanes that are not accessible by alkyne hydrosilylation or sila-Heck-type processes. A variety of silanes can be utilized, including those that serve as nucleophilic partners in Hiyama cross-coupling reactions. Mechanistic studies using deuterium-labelled silanes are described.

| S-EPMC7679053 | biostudies-literature

Nickel-catalyzed trifluoromethylthiolation of Csp<sup>2</sup>-O bonds.

Project description:While nickel catalysts have previously been shown to activate even the least reactive Csp2-O bonds, i.e. aryl ethers, in the context of C-C bond formation, little is known about the reactivity limits and molecular requirements for the introduction of valuable functional groups under homogeneous nickel catalysis. We identified that due to the high reactivity of Ni-catalysts, they are also prone to react with existing or installed functional groups, which ultimately causes catalyst deactivation. The scope of the Ni-catalyzed coupling protocol will therefore be dictated by the reactivity of the functional groups towards the catalyst. Herein, we showed that the application of computational tools allowed the identification of matching functional groups in terms of suitable leaving groups and tolerated functional groups. This allowed for the development of the first efficient protocol to trifluoromethylthiolate Csp2-O bonds, giving the mild and operationally simple C-SCF3 coupling of a range of aryl, vinyl triflates and nonaflates. The novel methodology was also applied to biologically active and pharmaceutical relevant targets, showcasing its robustness and wide applicability.

| S-EPMC5635847 | biostudies-literature

Nickel-Catalyzed Cross-Coupling of Redox-Active Esters with Boronic Acids.

Project description:A transformation analogous in simplicity and functional group tolerance to the venerable Suzuki cross-coupling between alkyl-carboxylic acids and boronic acids is described. This Ni-catalyzed reaction relies upon the activation of alkyl carboxylic acids as their redox-active ester derivatives, specifically N-hydroxy-tetrachlorophthalimide (TCNHPI), and proceeds in a practical and scalable fashion. The inexpensive nature of the reaction components (NiCl2 ?6?H2 O-$9.5?mol(-1) , Et3 N) coupled to the virtually unlimited commercial catalog of available starting materials bodes well for its rapid adoption.

| S-EPMC5232357 | biostudies-literature

Nickel-Catalyzed Decarbonylative Stannylation of Acyl Fluorides under Ligand-Free Conditions.

Project description:Nickel-catalyzed decarbonylative stannylation of acyl fluorides under ligand-free conditions was disclosed. A variety of aromatic acyl fluorides are capable of reacting with silylstannanes in the presence of cesium fluoride. A one-pot decarbonylative stannylation/Migita-Kosugi-Stille reaction of benzoyl fluoride, giving rise to the direct formation of the corresponding cross-coupled products, further demonstrated the synthetic utility of the present method. This newly developed methodology with a good functional-group compatibility via C-F bond cleavage and C-Sn bond formation under nickel catalysis opens a new area for the functionalization of acyl fluorides in terms of carbon-heteroatom bond formation.

| S-EPMC6539589 | biostudies-literature

Nickel-Catalyzed Enantioselective Cross-Coupling of N-Hydroxyphthalimide Esters with Vinyl Bromides.

Project description:An enantioselective Ni-catalyzed cross-coupling of N-hydroxyphthalimide esters with vinyl bromides is reported. The reaction proceeds under mild conditions and uses tetrakis(N,N-dimethylamino)ethylene as a terminal organic reductant. Good functional group tolerance is demonstrated, with over 20 examples of reactions that proceed with >90% ee.

| S-EPMC5868419 | biostudies-literature

Enantiomerically Enriched α-Borylzinc Reagents by Nickel-Catalyzed Carbozincation of Vinylboronic Esters.

Project description:In this paper is described a synthesis of enantiomerically enriched, configurationally stable organozinc reagents by catalytic enantioselective carbozincation of a vinylboronic ester. This process furnishes enantiomerically enriched α-borylzinc intermediates that are shown to undergo stereospecific reactions, producing enantioenriched secondary boronic ester products. The properties of the intermediate α-borylzinc reagent are probed and the synthetic utility of the products is demonstrated by application to the synthesis of (-)-aphanorphine and (-)-enterolactone.

| S-EPMC8859859 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data