Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Synthesis of α-heterosubstituted ketones through sulfur mediated difunctionalization of internal alkynes.

ABSTRACT: Synthesis of α-heterosubstituted ketones was achieved through sulfur mediated difunctionalization of internal alkynes in one pot. The reaction design involves: phenyl substituted internal alkyne attacking triflic anhydride activated diphenyl sulfoxide to give a sulfonium vinyl triflate intermediate, hydrolysis to give an α-sulfonium ketone, and then substitution with various nucleophiles. This method provides a unified route to access α-amino ketones, α-acyloxy ketones, α-thio ketones, α-halo ketones, α-hydroxy ketones, and related heterocyclic structures, in a rapid fashion.

SUBMITTER: Zhang Z

PROVIDER: S-EPMC6524669 | biostudies-other | 2019 May

REPOSITORIES: biostudies-other

ACCESS DATA

Json Xml

Publications

Synthesis of α-heterosubstituted ketones through sulfur mediated difunctionalization of internal alkynes.

Zhang Zhong Z Luo Yuzheng Y Du Hongguang H Xu Jiaxi J Li Pingfan P

Chemical science 20190416 19

Synthesis of α-heterosubstituted ketones was achieved through sulfur mediated difunctionalization of internal alkynes in one pot. The reaction design involves: phenyl substituted internal alkyne attacking triflic anhydride activated diphenyl sulfoxide to give a sulfonium vinyl triflate intermediate, hydrolysis to give an α-sulfonium ketone, and then substitution with various nucleophiles. This method provides a unified route to access α-amino ketones, α-acyloxy ketones, α-thio ketones, α-halo ke ...[more]

PMID: 31183068

Similar Datasets

Alkynes as equivalents of alpha-diazo ketones in generating alpha-oxo metal carbenes: a gold-catalyzed expedient synthesis of dihydrofuran-3-ones.

Project description:An expedient and reliable method for accessing reactive alpha-oxo gold carbenes via gold-catalyzed intermolecular oxidation of terminal alkynes has been developed. Significantly, this method offers a safe and economical alternative to the strategies based on diazo substrates. Its synthetic potential is demonstrated by expedient preparation of dihydrofuran-3-ones containing a broad range of functional groups.

| S-EPMC2847863 | biostudies-literature

Palladium(ii)-catalyzed synthesis of indenones through the cyclization of benzenecarbaldehydes with internal alkynes.

Project description:The palladium(ii)-catalyzed carbocyclization of benzenecarbaldehydes with internal alkynes to afford 2,3-disubstituted indenones was reported. The annulation reaction proceeded through the transmetalation of Pd(ii) with an aromatic aldehyde and the insertion of internal alkynes, followed by cyclization via the intramolecular nucleophilic addition of intermediate organopalladium(ii) species to the aldehyde group. This reaction proceeded in moderate to good yields with high regioselectivity.

| S-EPMC9072296 | biostudies-literature

Enantioselective synthesis of α-amino ketones through palladium-catalyzed asymmetric arylation of α-keto imines.

Project description:Chiral α-amino ketones are common structural motifs in natural products and pharmaceuticals, as well as important synthons in organic synthesis. Thus, establishing efficient methods for preparing compounds with these privileged scaffolds is an important endeavor in synthetic chemistry. Herein we disclose a new catalytic asymmetric approach for the synthesis of chiral α-amino ketones through a chiral palladium-catalyzed arylation reaction of in situ generated challenging α-keto imines from previously unreported C-acyl N-sulfonyl-N,O-aminals, with arylboronic acids. The current reaction offers a straightforward approach to the asymmetric synthesis of acyclic α-amino ketones in a practical and highly stereocontrolled manner. Meanwhile, the multiple roles of the chiral Pd(ii) complex catalyst in the reaction were also reported.

| S-EPMC8966749 | biostudies-literature

Zinc Iodide Catalyzed Synthesis of Trisubstituted Allenes from Terminal Alkynes and Ketones.

Project description:A straightforward, user-friendly, efficient protocol for the one pot, ZnI2-catalyzed allenylation of terminal alkynes with pyrrolidine and ketones, toward trisubstituted allenes, is described. Trisubstituted allenes can be obtained under either conventional heating or microwave irradiation conditions, which significantly reduces the reaction time. A sustainable, widely available, and low-cost metal salt catalyst is employed, and the reactions are carried out under solvent-free conditions. Among others, synthetically valuable allenes bearing functionalities such as amide, hydroxyl, or phthalimide can be efficiently prepared. Mechanistic experiments, including kinetic isotope effect measurements and density functional theory (DFT) calculations, suggest a rate-determining [1,5]-hydride transfer during the transformation of the intermediate propargylamine to the final allene.

| S-EPMC8444324 | biostudies-literature

Decarboxylative benzylations of alkynes and ketones.

Project description:Benzyl esters of propiolic and beta-keto acids undergo catalytic decarboxylative coupling when treated with appropriate palladium catalysts. Such decarboxylative couplings allow the benzylation of alkynes without the use of strong bases and/or organometallics. This allows the synthesis of sensitive benzylic alkynes that are prone to undergo isomerizations under basic conditions. Additionally, decarboxylation facilitates the site-specific benzylation of diketones and ketoesters under mild, base-free conditions. Ultimately, the methodology described expands our ability to cross-couple medicinally relevant heterocycles.

| S-EPMC2923406 | biostudies-literature

Continuous-flow hydration-condensation reaction: Synthesis of α,β-unsaturated ketones from alkynes and aldehydes by using a heterogeneous solid acid catalyst.

Project description:A simple, practical and efficient continuous-flow hydration-condensation protocol was developed for the synthesis of α,β-unsaturated ketones starting from alkynes and aldehydes by employing a heterogeneous catalyst in a flow microwave. The procedure presents a straightforward and convenient access to valuable differently substituted chalcones and can be applied on multigram scale.

| S-EPMC3252873 | biostudies-literature

α-Diimine synthesis <i>via</i> titanium-mediated multicomponent diimination of alkynes with C-nitrosos.

Project description:α-Diimines are commonly used as supporting ligands for a variety of transition metal-catalyzed processes, most notably in α-olefin polymerization. They are also precursors to valuable synthetic targets, such as chiral 1,2-diamines. Their synthesis is usually performed through acid-catalyzed condensation of amines with α-diketones. Despite the simplicity of this approach, accessing unsymmetrical α-diimines is challenging. Herein, we report the Ti-mediated intermolecular diimination of alkynes to afford a variety of symmetrical and unsymmetrical α-diimines through the reaction of diazatitanacyclohexadiene intermediates with C-nitrosos. These diazatitanacycles can be readily accessed in situ via the multicomponent coupling of Ti[triple bond, length as m-dash]NR imidos with alkynes and nitriles. The formation of α-diimines is achieved through formal [4 + 2]-cycloaddition of the C-nitroso to the Ti and γ-carbon of the diazatitanacyclohexadiene followed by two subsequent cycloreversion steps to eliminate nitrile and afford the α-diimine and a Ti oxo.

| S-EPMC8809399 | biostudies-literature

Iodine-mediated hydration of alkynes on keto-functionalized scaffolds: mechanistic insight and the regiospecific hydration of internal alkynes.

Project description:An iodine-mediated hydration reaction of alkynes serves as a green alternative to metal-catalyzed procedures. Previous work has shown that this method works well with terminal alkynes on keto-functionalized scaffolds, including 1,3-dicarbonyls and their heteroatom analogues. It was hypothesized that the reaction proceeds through a 5-exo-dig neighboring group participation (NGP) cyclization and an α-iodo intermediate. The work described herein probes the existence of the intermediate through NMR investigations and explores the scope of the hydration process with internal alkynes. The NMR experiments confirm the existence of the α-iodo intermediate, and methodology studies demonstrate that alkyl-capped, asymmetric, internal alkynes undergo a regiospecific hydration, also via the 5-exo-dig NGP pathway.

| S-EPMC6880791 | biostudies-literature

Hypervalent Iodine-Mediated Diastereoselective α-Acetoxylation of Cyclic Ketones.

Project description:A binary hybrid system comprising a hypervalent iodine(III) reagent and BF3•OEt2 Lewis acid was found to be effective for the diastereoselective α-acetoxylation of cyclic ketones. In this hybrid system, BF3•OEt2 Lewis acid allowed the activation of the hypervalent iodine(III) reagent and cyclic ketones for smooth α-acetoxylation reaction, achieving high diastereoselectivity. This hypervalent iodine-mediated α-acetoxylation of the cyclic ketone reaction plausibly undergoes an SN2 substitution mechanism via an α-C-bound hypervalent iodine intermediate. The diastereoselectivity of the reaction mainly originates from thermodynamic control.

| S-EPMC7365914 | biostudies-literature

Enantio- and Diastereoselective Synthesis of Functionalized Carbocycles by Cu-Catalyzed Borylative Cyclization of Alkynes with Ketones.

Project description:A single-pot Cu-catalyzed enantio- and diastereoselective tandem hydroboration/borylative cyclization of alkynes with ketones for the synthesis of carbocycles is reported. The reaction proceeds via desymmetrization and generates four contiguous stereocenters, including an all-carbon quaternary center. The method provides rapid access to [6,5]- and [5,5]-bicycles and cyclopentane products. Catalyst-controlled diastereoselectivity by selection of bisphosphine ligand is noted. Utility of the products is demonstrated by site- and chemoselective transformations that afford valuable alkenyl and allyl organoborons.

| S-EPMC6702961 | 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