Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Cationic-oxazaborolidine-catalyzed enantioselective Diels-Alder reaction of alpha,beta-unsaturated acetylenic ketones.

ABSTRACT:

SUBMITTER: Payette JN

PROVIDER: S-EPMC2779767 | biostudies-literature | 2009

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

Cationic-oxazaborolidine-catalyzed enantioselective Diels-Alder reaction of alpha,beta-unsaturated acetylenic ketones.

Payette Joshua N JN Yamamoto Hisashi H

Angewandte Chemie (International ed. in English) 20090101 43

PMID: 19774587

Similar Datasets

Computational evaluation of enantioselective Diels-Alder reactions mediated by Corey's cationic oxazaborolidine catalysts.

Project description:The cationic oxazaborolidine-catalyzed Diels-Alder reactions of butadiene and a series of five dienophiles have been studied using density functional theory (B3LYP/6-31G(d)). In each case, the computational results successfully reproduce the experimentally observed sense of stereoinduction and enantiomeric ratio. The computed structures of the lowest energy Lewis acid-carbonyl complexes and Lewis acid-transition state complexes are closely related to the models for stereoselection proposed by Corey and co-workers.

| S-EPMC2631179 | biostudies-literature

A chiral cobalt(ii) complex catalyzed enantioselective aza-Piancatelli rearrangement/Diels-Alder cascade reaction.

Project description:A chiral N,N'-dioxide/cobalt(ii) complex catalyzed highly diastereoselective and enantioselective tandem aza-Piancatelli rearrangement/intramolecular Diels-Alder reaction has been disclosed. Various valuable hexahydro-2a,5-epoxycyclopenta[cd]isoindoles bearing six contiguous stereocenters have been obtained in good yields with excellent diastereo- and enantio-selectivities from a wide range of both readily available 2-furylcarbinols and N-(furan-2-ylmethyl)anilines.

| S-EPMC8152720 | biostudies-literature

Chiral N-heterocyclic carbene-catalyzed generation of ester enolate equivalents from {alpha},{beta}-unsaturated aldehydes for enantioselective Diels-Alder reactions.

Project description:The catalytic generation of chiral ester enolate equivalents from ?,?-unsaturated aldehydes with chiral N-hetereocyclic carbene catalysts makes possible highly enantioselective hetero-Diels-Alder reactions. The reactions proceed under simple, mild conditions with both aliphatic and aromatic substituted enals as substrates. Previous attempts to employ these starting materials as enolate precursors gave structurally different products via catalytically generated homoenolate equivalents. Critical to the success of the enolate generation was the strength of the catalytic base used to generate the active N-heterocyclic carbene catalyst. To complement these studies, we have investigated the enolate structure using computational methods and find that it prefers conformations perpendicular to the triazolium core.

| S-EPMC2996418 | biostudies-other

Enantioselective Diels-Alder reaction of anthracene by chiral tritylium catalysis.

Project description:The combination of the trityl cation and a chiral weakly coordinating Fe(III)-based bisphosphate anion was used to develop a new type of a highly active carbocation Lewis acid catalyst. The stereocontrol potential of the chiral tritylium ion pair was demonstrated by its application in an enantioselective Diels-Alder reaction of anthracene.

| S-EPMC6604712 | biostudies-literature

CuH-catalyzed enantioselective 1,2-reductions of alpha,beta-unsaturated ketones.

Project description:The first study on a general technology for arriving at valued nonracemic allylic alcohols using asymmetric ligand-accelerated catalysis by copper hydride is described.

| S-EPMC3365512 | biostudies-literature

Electric field-catalyzed single-molecule Diels-Alder reaction dynamics.

Project description:Precise time trajectories and detailed reaction pathways of the Diels-Alder reaction were directly observed using accurate single-molecule detection on an in situ label-free single-molecule electrical detection platform. This study demonstrates the well-accepted concerted mechanism and clarifies the role of charge transfer complexes with endo or exo configurations on the reaction path. An unprecedented stepwise pathway was verified at high temperatures in a high-voltage electric field. Experiments and theoretical results revealed an electric field-catalyzed mechanism that shows the presence of a zwitterionic intermediate with one bond formation and variation of concerted and stepwise reactions by the strength of the electric field, thus establishing a previously unidentified approach for mechanistic control by electric field catalysis.

| S-EPMC7817103 | biostudies-literature

Primary amine-catalyzed enantioselective 1,4-Michael addition reaction of pyrazolin-5-ones to α,β-unsaturated ketones.

Project description:The enantioselective 1,4-addition reaction of pyrazolin-5-ones to α,β-unsaturated ketones catalyzed by a cinchona alkaloid-derived primary amine-Brønsted acid composite is reported. Both enantiomers of the anticipated pyrazole derivatives were obtained in good to excellent yields (up to 97%) and high enantioselectivities (up to 98.5% ee) under mild reaction conditions. In addition, this protocol was further expanded to synthesize highly enantioenriched hybrid molecules bearing biologically relevant heterocycles.

| S-EPMC11250233 | biostudies-literature

Enantioselective synthesis of (+)-estrone exploiting a hydrogen bond-promoted Diels-Alder reaction.

Project description:Starting from Dane's diene and methylcyclopentenedione, (+)-estrone is synthesized along the Quinkert-Dane route in 24% total yield. The key step is an enantioselective Diels-Alder reaction promoted by an amidinium catalyst as efficiently as by a traditional Ti-TADDOLate Lewis acid.

| S-EPMC2852147 | biostudies-literature

Iridium-catalyzed enantioselective allylic substitution of unstabilized enolates derived from ?,?-unsaturated ketones.

Project description:We report Ir-catalyzed, enantioselective allylic substitution reactions of unstabilized silyl enolates derived from ?,?-unsaturated ketones. Asymmetric allylic substitution of a variety of allylic carbonates with silyl enolates gave allylated products in 62-94% yield with 90-98% ee and >20:1 branched-to-linear selectivity. The synthetic utility of this method was illustrated by the short synthesis of an anticancer agent, TEI-9826.

| S-EPMC4159307 | biostudies-literature

Lewis acid catalyzed inverse-electron-demand Diels-Alder reaction of tropones.

Project description:Lewis acid catalyzed inverse-electron-demand Diels-Alder reaction of tropone derivatives was developed. Up to 97% ee was obtained for the chiral dinucleus BINOL-aluminum complex catalyzed reaction between tropones and ketene diethyl acetal to give bicyclo[3.2.2] ring structures, which opens up a unique way of making chiral seven-membered rings.

| S-EPMC2810398 | 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