Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Direct prenylation of aromatic and alpha,beta-unsaturated carboxamides via iridium-catalyzed C-H oxidative addition-allene insertion.

ABSTRACT: Exposure of aromatic carboxamides 1e-1m, heteroaromatic carboxamides 1n-1p, and alpha,beta-unsaturated carboxamides 1q-1s to 1,1-dimethylallene in the presence of the a cationic iridium complex derived from [Ir(cod)(2)]BAr(F)(4) and rac-BINAP results in direct C-H prenylation to furnish adducts 2e-2m, 2n-2p, and 2q-2s, respectively, in good isolated yields as single isomers.

SUBMITTER: Zhang YJ

PROVIDER: S-EPMC2858454 | biostudies-literature | 2009 Sep

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

Direct prenylation of aromatic and alpha,beta-unsaturated carboxamides via iridium-catalyzed C-H oxidative addition-allene insertion.

Zhang Yong Jian YJ Skucas Eduardas E Krische Michael J MJ

Organic letters 20090901 18

Exposure of aromatic carboxamides 1e-1m, heteroaromatic carboxamides 1n-1p, and alpha,beta-unsaturated carboxamides 1q-1s to 1,1-dimethylallene in the presence of the a cationic iridium complex derived from [Ir(cod)(2)]BAr(F)(4) and rac-BINAP results in direct C-H prenylation to furnish adducts 2e-2m, 2n-2p, and 2q-2s, respectively, in good isolated yields as single isomers. ...[more]

PMID: 19739691

Similar Datasets

Magnesium-catalyzed asymmetric direct aldol addition of ethyl diazoacetate to aromatic, aliphatic, and alpha,beta-unsaturated aldehydes.

Project description:Magnesium-catalyzed enantioselective aldol between ethyl diazoacetate and aromatic, aliphatic, and alpha,beta-unsaturated aldehydes affords alpha-diazo-beta-hydroxy-esters in high enantioselectivities. Aldol adducts resulting from this asymmetric transformation are versatile intermediates toward the synthesis of several ester containing chiral building blocks.

| S-EPMC2652472 | biostudies-literature

Iridium-catalyzed hydrocarboxylation of 1,1-dimethylallene: byproduct-free reverse prenylation of carboxylic acids.

Project description:Exposure of carboxylic acids 1a-12a to commercially available 1,1-dimethylallene in the presence of substoichiometric quantities of an iridium catalyst prepared in situ from [Ir(cod)Cl]2 and BIPHEP provides the corresponding 1,1-dimethylallyl (reverse prenyl) esters 1b-12b in 74-92% isolated yield. This protocol represents the first branch-regioselective allene hydrocarboxylation. Stoichiometric byproducts are not generated in this process and protecting groups are not required for alcohols, phenols, and indolic amines.

| S-EPMC2868924 | biostudies-literature

Direct Conversion of Primary Alcohols to 1,2-Amino Alcohols: Enantioselective Iridium-Catalyzed Carbonyl Reductive Coupling of Phthalimido-Allene via Hydrogen Auto-Transfer.

Project description:The first catalytic enantioselective carbonyl (?-amino)allylations are described. Phthalimido-allene 1 and primary alcohols 2a-2z, 2a'-2c' engage in hydrogen auto-transfer-mediated carbonyl reductive coupling by way of (?-amino)allyliridium-aldehyde pairs to form vicinal amino alcohols 3a-3z, 3a'-3c' with high levels of regio-, anti-diastereo-, and enantioselectivity. Reaction progress kinetic analysis and isotopic labeling studies corroborate a catalytic cycle involving turnover-limiting alcohol dehydrogenation followed by rapid allene hydrometalation.

| S-EPMC6739137 | 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

Mechanism of the Iridium-Catalyzed Silylation of Aromatic C-H Bonds.

Project description:Phenanthroline ligands and [Ir(cod)(OMe)]2 form complexes that catalyze the silylation of aromatic and aliphatic C-H bonds. However, no experimental data on the identity of complexes related to the mechanism of this process or the mechanisms by which they react to functionalize C-H bonds have been reported. Herein, we describe our studies on the mechanism of the iridium-catalyzed silylation of aryl C-H bonds. The resting state of the catalyst is an iridium disilyl hydride complex (phenanthroline)Ir(SiMe(OTMS)2)2(H)(L), in which L varies with the arene and additives. An iridium disilyl hydride complex was isolated, characterized, and allowed to react with arenes to form aryl silanes. The kinetics of the reactions of electron-rich and electron-poor arenes showed that the rate-limiting step varies with the electronic properties of the arene. Computational studies on related iridium silyl complexes revealed that the high activity of iridium complexes containing sterically encumbered phenanthroline ligands is due to a change in the number of silyl groups bound to iridium between the resting state of the catalyst containing the hindered phenanthroline and that containing less-hindered phenanthroline.

| S-EPMC7660231 | biostudies-literature

Pd-catalyzed carbonylative conjugate addition of dialkylzinc reagents to unsaturated carbonyls.

Project description:The Pd-catalyzed addition of organozinc reagents to unsaturated carbonyls in the presence of carbon monoxide provides 1,4-diketones in good yield. The reaction was studied with a number of substituted cyclic and acyclic ketones as well as alpha,beta-unsaturated aldehydes.

| S-EPMC2929296 | biostudies-literature

Iridium-catalyzed enantioselective direct vinylogous allylic alkylation of coumarins.

Project description:The first iridium-catalyzed enantioselective vinylogous allylic alkylation of coumarins is presented. Using easily accessible linear allylic carbonates as the allylic electrophile, this reaction installs unfunctionalized allyl groups at the ?-position of 4-methylcoumarins in an exclusively branched-selective manner generally in high yields with an excellent level of enantioselectivity (up to 99?:?1 er).

| S-EPMC6050583 | biostudies-literature

Iridium-catalyzed, regio- and enantioselective allylic substitution with aromatic and aliphatic sulfinates.

Project description:The iridium-catalyzed allylation of sodium sulfinate to form branched allylic sulfones is reported. The reactions between various sodium sulfinates and achiral allylic carbonates occur in good yields, with high selectivity for the branched isomer, and high enantioselectivities (up to 98% ee).

| S-EPMC2802463 | biostudies-other

Enantioselective carbonyl allylation, crotylation, and tert-prenylation of furan methanols and furfurals via iridium-catalyzed transfer hydrogenation.

Project description:5-Substituted-2-furan methanols 1a-c are subject to enantioselective carbonyl allylation, crotylation and tert-prenylation upon exposure to allyl acetate, alpha-methyl allyl acetate, or 1,1-dimethylallene in the presence of an ortho-cyclometalated iridium catalyst modified by (R)-Cl,MeO-BIPHEP, (R)-C3-TUNEPHOS, and (R)-C3-SEGPHOS, respectively. In the presence of 2-propanol, but under otherwise identical conditions, the corresponding substituted furfurals 2a-c are converted to identical products of allylation, crotylation, and tert-prenylation. Optically enriched products of carbonyl allylation, crotylation, and reverse prenylation 3b, 4b, and 5b were subjected to Achmatowicz rearrangement to furnish the corresponding gamma-hydroxy-beta-pyrones 6a-c, respectively, with negligible erosion of enantiomeric excess.

| S-EPMC2830394 | biostudies-literature

Isothiourea-Catalyzed Enantioselective Michael Addition of Malonates to α,β-Unsaturated Aryl Esters.

Project description:An enantioselective Michael addition of malonates to α,β-unsaturated para-nitrophenyl esters was achieved using the Lewis basic isothiourea HyperBTM, giving excellent levels of product enantioselectivity (up to >99:1 enantiomeric ratio) in good yields and with complete regioselectivity (>20:1 regioselectivity ratio) in the presence of alternative (phenyl ketone and ethyl ester) Michael acceptors. Density functional theory calculations indicate that N-acylation is rate-limiting. This constitutes a rare example of a highly enantioselective addition of simple, readily available malonates to α,β-unsaturated esters.

| S-EPMC9278409 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

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