Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Organocatalysis in radical chemistry. Enantioselective alpha-oxyamination of aldehydes.

ABSTRACT:

SUBMITTER: Sibi MP

PROVIDER: S-EPMC2632679 | biostudies-literature | 2007 Apr

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

Organocatalysis in radical chemistry. Enantioselective alpha-oxyamination of aldehydes.

Sibi Mukund P MP Hasegawa Masayuki M

Journal of the American Chemical Society 20070316 14

PMID: 17362013

Similar Datasets

Enantioselective alpha-trifluoromethylation of aldehydes via photoredox organocatalysis.

Project description:The first enantioselective, organocatalytic alpha-trifluoromethylation and alpha-perfluoroalkylation of aldehydes have been accomplished using a readily available iridium photocatalyst and a chiral imidazolidinone catalyst. A range of alpha-trifluoromethyl and alpha-perfluoroalkyl aldehydes were obtained from commercially available perfluoroalkyl halides with high efficiency and enantioselectivity. The resulting alpha-trifluoromethyl aldehydes were subsequently shown to be versatile precursors for the construction of a variety of enantioenriched trifluoromethylated building blocks.

| S-EPMC3310169 | biostudies-literature

Enantioselective α-benzylation of aldehydes via photoredox organocatalysis.

Project description:The first enantioselective aldehyde α-benzylation using electron-deficient aryl and heteroaryl substrates has been accomplished. The productive merger of a chiral imidazolidinone organocatalyst and a commercially available iridium photoredox catalyst in the presence of household fluorescent light directly affords the desired homobenzylic stereogenicity in good to excellent yield and enantioselectivity. The utility of this methodology has been demonstrated via rapid access to an enantioenriched drug target for angiogenesis suppression.

| S-EPMC3056320 | biostudies-literature

Enantioselective Formal α-Methylation and α-Benzylation of Aldehydes by Means of Photo-organocatalysis.

Project description:Detailed herein is the photochemical organocatalytic enantioselective α-alkylation of aldehydes with (phenylsulfonyl)alkyl iodides. The chemistry relies on the direct photoexcitation of enamines to trigger the formation of reactive carbon-centered radicals from iodosulfones, while the ground-state chiral enamines provide effective stereochemical control over the radical trapping process. The phenylsulfonyl moiety, acting as a redox auxiliary group, facilitates the generation of radicals. In addition, it can eventually be removed under mild reducing conditions to reveal methyl and benzyl groups.

| S-EPMC5396335 | biostudies-literature

Enantioselective α-arylation of aldehydes via the productive merger of iodonium salts and organocatalysis.

Project description:The enantioselective α-arylation of aldehydes has been accomplished using diaryliodonium salts and a combination of copper and organic catalysts. These mild catalytic conditions provide a new strategy for the enantioselective construction and retention of enolizable α-formyl benzylic stereocenters, a valuable synthon for the production of medicinal agents. As one example, this new asymmetric protocol has been applied to the rapid synthesis of (S)-ketoprofen, a commercially successful oral and topical analgesic.

| S-EPMC3082494 | biostudies-literature

Merger of Visible Light-Driven Chiral Organocatalysis and Continuous Flow Chemistry: An Accelerated and Scalable Access into Enantioselective α-Alkylation of Aldehydes.

Project description:The electron donor-acceptor complex-enabled asymmetric photochemical alkylation strategy holds potential to attain elusive chiral α-alkylated aldehydes without an external photoredox catalyst. The photosensitizer-free conditions are beneficial concerning process costs and sustainability. However, lengthy organocatalyst preparation steps as well as limited productivity and difficult scalability render the current approaches unsuitable for synthesis on enlarged scales. Inspired by these limitations, a protocol was developed for the enantioselective α-alkylation of aldehydes based on the synergistic combination of visible light-driven asymmetric organocatalysis and a controlled continuous flow reaction environment. With the aim to reduce process costs, a commercially available chiral catalyst has been exploited to achieve photosensitizer-free enantioselective α-alkylations using phenacyl bromide derivates as alkylating agents. As a result of elaborate optimization and process development, the present flow strategy furnishes an accelerated and inherently scalable entry into enantioenriched α-alkylated aldehydes including a chiral key intermediate of the antirheumatic esonarimod.

| S-EPMC10952295 | biostudies-literature

Enantioselective α-Alkylation of Aldehydes by Photoredox Organocatalysis: Rapid Access to Pharmacophore Fragments from β-Cyanoaldehydes.

Project description:The combination of photoredox catalysis and enamine catalysis has enabled the development of an enantioselective α-cyanoalkylation of aldehydes. This synergistic catalysis protocol allows for the coupling of two highly versatile yet orthogonal functionalities, allowing rapid diversification of the oxonitrile products to a wide array of medicinally relevant derivatives and heterocycles. This methodology has also been applied to the total synthesis of the lignan natural product (-)-bursehernin.

| S-EPMC4548807 | biostudies-literature

Enantioselective aldehyde alpha-nitroalkylation via oxidative organocatalysis.

Project description:The first enantioselective organocatalytic alpha-nitroalkylation of aldehydes has been accomplished. The aforementioned process involves the oxidative coupling of an enamine intermediate, generated transiently via condensation of an amine catalyst with an aldehyde, with a silyl nitronate to produce a beta-nitroaldehyde. Two methods, one that furnishes the syn beta-nitroaldehyde and a second that provides access to the anti isomer, have been developed. Data are presented to support a hypothesis that explains this phenomenon in terms of a silyl group-controlled change in mechanism. Finally, a three-step procedure for the synthesis of both syn- and anti-alpha,beta-disubstituted beta-amino acids is presented.

| S-EPMC3259685 | biostudies-literature

The productive merger of iodonium salts and organocatalysis: a non-photolytic approach to the enantioselective alpha-trifluoromethylation of aldehydes.

Project description:An enantioselective organocatalytic alpha-trifluoromethylation of aldehydes has been accomplished using a commercially available, electrophilic trifluoromethyl source. The merging of Lewis acid and organocatalysis provides a new strategy for the enantioselective construction of trifluoromethyl stereogenicity, an important chiral synthon for pharmaceutical, materials, and agrochemical applications. This mild and operationally simple protocol allows rapid access to enantioenriched alpha-trifluoromethylated aldehydes through a nonphotolytic pathway.

| S-EPMC2880471 | biostudies-literature

Enantioselective catalytic radical decarbonylative azidation and cyanation of aldehydes.

Project description:Empowered by the ubiquity of carbonyl functional groups in organic compounds, decarbonylative functionalization was prevalent in the construction of complex molecules. Under this context, asymmetric decarbonylative functionalization has emerged as an efficient pathway to accessing chiral motifs. However, ablation of enantiomeric control in a conventional 2e transition metal-catalyzed process was notable because of harsh conditions (high temperatures, etc.) that are usually required. To address this challenge and use readily accessible aldehyde directly, we report the asymmetric radical decarbonylative azidation and cyanation. Diverse aldehydes were directly used as alkyl radical precursor, engaging in the subsequent inner-sphere or outer-sphere ligand transfer where functional motifs (CN and N3) could be incorporated in excellent site- and enantioselectivity. Mild conditions, broad scope, excellent regioselectivity (driven by polarity-matching strategy), and enantioselectivity were shown for both transformations. This radical decarbonylative strategy using aldehydes as alkyl radical precursor has offered a powerful reaction manifold in asymmetric radical transformations to construct functional motifs regio- and stereoselectively.

| S-EPMC10854440 | biostudies-literature

Single-Flask Enantioselective Synthesis of α-Amino Acid Esters by Organocatalysis.

Project description:An operationally simple Knoevenagel condensation/asymmetric epoxidation/domino ring-opening esterification (DROE) approach has been disclosed to successfully access a good variety of (R)- and (S)-α-arylglycine esters from commercially available aldehydes, phenylsulfonyl acetonitrile, cumyl hydroperoxide, anilines, and readily available Cinchona alkaloid-based catalysts using a single solvent and reaction vessel. DFT calculations performed on the key asymmetric epoxidation showed the importance of cooperative H-bonding interactions in affecting the stereocontrol.

| S-EPMC10353036 | 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