Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Thiourea-catalyzed enantioselective cyanosilylation of ketones.

ABSTRACT: The new chiral amino thiourea catalyst 3d promotes the highly enantioselective cyanosilylation of a wide variety of ketones. The hindered tertiary amine substituent plays a crucial role with regard to both stereoinduction and reactivity, suggesting a cooperative mechanism involving electrophile activation by thiourea and nucleophile activation by the amine.

SUBMITTER: Fuerst DE

PROVIDER: S-EPMC3166885 | biostudies-literature | 2005 Jun

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

Thiourea-catalyzed enantioselective cyanosilylation of ketones.

Fuerst Douglas E DE Jacobsen Eric N EN

Journal of the American Chemical Society 20050601 25

The new chiral amino thiourea catalyst 3d promotes the highly enantioselective cyanosilylation of a wide variety of ketones. The hindered tertiary amine substituent plays a crucial role with regard to both stereoinduction and reactivity, suggesting a cooperative mechanism involving electrophile activation by thiourea and nucleophile activation by the amine. ...[more]

PMID: 15969569

Similar Datasets

Enantioselective thiourea-catalyzed cationic polycyclizations.

Project description:A new thiourea catalyst is reported for the enantioselective cationic polycyclization of hydroxylactams. Both the yield and enantioselectivity of this transformation were found to vary strongly with the identity of a single aromatic residue on a common catalyst framework, with more expansive and polarizable arenes proving optimal. Evidence is presented for a mechanism in which stabilizing cation-pi interactions are a principal determinant of enantioselectivity.

| S-EPMC2989498 | biostudies-literature

Chromium(II)-catalyzed enantioselective arylation of ketones.

Project description:The chromium-catalyzed enantioselective addition of carbo halides to carbonyl compounds is an important transformation in organic synthesis. However, the corresponding catalytic enantioselective arylation of ketones has not been reported to date. Herein, we report the first Cr-catalyzed enantioselective addition of aryl halides to both arylaliphatic and aliphatic ketones with high enantioselectivity in an intramolecular version, providing facile access to enantiopure tetrahydronaphthalen-1-ols and 2,3-dihydro-1H-inden-1-ols containing a tertiary alcohol.

| S-EPMC5238525 | biostudies-other

Enantioselective, organocatalytic reduction of ketones using bifunctional thiourea-amine catalysts.

Project description:Prochiral ketones are reduced to enantioenriched, secondary alcohols using catecholborane and a family of air-stable, bifunctional thiourea-amine organocatalysts. Asymmetric induction is proposed to arise from the in situ complexation between the borane and chiral thiourea-amine organocatalyst resulting in a stereochemically biased boronate-amine complex. The hydride in the complex is endowed with enhanced nucleophilicity while the thiourea concomitantly embraces and activates the carbonyl.

| S-EPMC2860298 | biostudies-literature

Enantioselective thiourea-catalyzed additions to oxocarbenium ions.

Project description:Asymmetric, catalytic reactions of oxocarbenium ions are reported. Simple, chiral urea and thiourea derivatives are shown to catalyze the enantioselective substitution of silyl ketene acetals onto 1-chloroisochromans. A mechanism involving anion binding by the chiral catalyst to generate a reactive oxocarbenium ion is invoked. Catalysts bearing tertiary benzylic amide groups afforded highest enantioselectivities, with the optimal structure being derived from enantioenriched 2-arylpyrrolidine derivatives.

| S-EPMC2574628 | biostudies-literature

Enantioselective thiourea-catalyzed intramolecular cope-type hydroamination.

Project description:Catalysis of Cope-type rearrangements of bis-homoallylic hydroxylamines is demonstrated using chiral thiourea derivatives. This formal intramolecular hydroamination reaction provides access to highly enantioenriched ?-substituted pyrrolidine products and represents a complementary approach to metal-catalyzed methods.

| S-EPMC3689223 | biostudies-literature

Thiourea-catalyzed enantioselective iso-Pictet-Spengler reactions.

Project description:A one-pot condensation of isotryptamines and aldehydes that affords enantiomerically enriched 4-substituted tetrahydro-γ-carbolines is reported. The reaction is induced by a chiral thiourea/benzoic acid dual catalyst system. Purification of the N-Boc-protected products by trituration or crystallization provides the optically pure tetrahydro-γ-carboline derivatives in a scalable and highly practical procedure.

| S-EPMC3206290 | biostudies-literature

Quinidine thiourea-catalyzed aldol reaction of unactivated ketones: highly enantioselective synthesis of 3-alkyl-3-hydroxyindolin-2-ones.

Project description: Not available

| S-EPMC3086465 | biostudies-literature

Enantioselective Nickel-Catalyzed anti-Arylmetallative Cyclizations onto Acyclic Ketones.

Project description:Domino reactions involving nickel-catalyzed additions of (hetero)arylboronic acids to alkynes, followed by cyclization of the alkenylnickel intermediates onto tethered acyclic ketones to give chiral tertiary-alcohol-containing products in high enantioselectivities, are described. The reversible E/Z isomerization of the alkenylnickel intermediates enables overall anti-arylmetallative cyclization to occur. The ring system of the products are substructures of certain diarylindolizidine alkaloids.

| S-EPMC8048927 | 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

Computational Analysis of Enantioselective Pd-Catalyzed α-Arylation of Ketones.

Project description:The direct α-arylation of carbonyl compounds emerged over the last two decades as a straightforward method for the formation of C(sp3)-C(sp2) bonds. Mechanistic studies suggested a classical cross-coupling catalytic cycle. This consists of oxidative addition of the aryl halide (ArX) to the Pd(0)-catalyst, transmetallation of the Na- or K-enolate generated in situ, and subsequent reductive elimination. Even though the general reaction mechanism was thoroughly investigated, studies focusing on enantioselective variants of this transformation are rare. Here, the computational study of the [Pd(BINAP)]-catalyzed α-arylation of 2-methyltetralone with bromobenzene is reported. The whole reaction energy profile was computed and several mechanistic scenarios were investigated for the key steps of the reaction, which are the enolate transmetallation and the C-C bond-forming reductive elimination. Among the computed mechanisms, the reductive elimination from the C-bound enolate Pd complex was found to be the most favorable one, providing a good match with the stereoselectivity observed experimentally with different ligands and substrates. Detailed analysis of the stereodetermining transition structures allowed us to establish the origin of the reaction enantioselectivity.

| S-EPMC8009508 | 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