Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

An Improved Catalyst Architecture for Rhodium (III) Catalyzed C-H Activation and its Application to Pyridone Synthesis.

ABSTRACT: We have developed a method for preparing pyridones from the coupling reaction of acrylamides and alkynes with either stoichometric Cu(OAc)2 or catalytic Cu(OAc)2 and air as oxidants. In the course of these studies, it was found that a larger ligand, 1,3-di-tert-butylcyclopentadienyl (termed Cpt) results in higher degrees of regioselectivity in the alkyne insertion event. The transformation tolerates a broad variety of alkynes and acrylamides. Furthermore, Cpt and Cp* demonstrate similar catalytic activity. This similarity allows for mechanistic studies to be undertaken which suggest a difference in mechanism between this reaction and the previously studied benzamide system.

SUBMITTER: Hyster TK

PROVIDER: S-EPMC4286810 | biostudies-literature | 2011 Aug

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

An Improved Catalyst Architecture for Rhodium (III) Catalyzed C-H Activation and its Application to Pyridone Synthesis.

Hyster Todd K TK Rovis Tomislav T

Chemical science 20110801 8

We have developed a method for preparing pyridones from the coupling reaction of acrylamides and alkynes with either stoichometric Cu(OAc)2 or catalytic Cu(OAc)2 and air as oxidants. In the course of these studies, it was found that a larger ligand, 1,3-di-tert-butylcyclopentadienyl (termed Cpt) results in higher degrees of regioselectivity in the alkyne insertion event. The transformation tolerates a broad variety of alkynes and acrylamides. Furthermore, Cp ...[more]

PMID: 25580208

Similar Datasets

Combining the Ugi-azide multicomponent reaction and rhodium(III)-catalyzed annulation for the synthesis of tetrazole-isoquinolone/pyridone hybrids.

Project description:An efficient sequence based on the Ugi-azide reaction and rhodium(III)-catalyzed intermolecular annulation has been established for the preparation of tetrazole-isoquinolone/pyridone hybrids. Several N-acylaminomethyltetrazoles were reacted with arylacetylenes to form the hybrid products in moderate to very good yields. The method relies on the capacity of the rhodium catalyst to promote C(sp2)-H activation in the presence of a suitable directing group. The Ugi-azide reaction provides broad molecular diversity and enables the introduction of the tetrazole moiety, which may further assist the catalytic reaction by coordinating the metal center. The scope of the isoquinolones is very wide and may be extended to the preparation of complex compounds having heterocyclic moieties such as pyridone, furan, thiophene and pyrrole, as well as the corresponding benzo-fused derivatives. The developed procedure is simple, reproducible and does not require inert conditions.

| S-EPMC6808192 | biostudies-literature

Rhodium(III)-Catalyzed C-H Activation Mediated Synthesis of Isoquinolones from Amides and Cyclopropenes.

Project description:We have developed a synthesis of 4-substituted isoquinolones from the Rh(III)-catalyzed, C-H activation mediated, coupling of O-pivaloyl benzhydroxamic acids and 3,3-disubstituted cyclopropenes. Experiments suggest the formation of a [4.1.0] bicyclic-system, which can open under acidic conditions to generate the desired isoquinolone.

| S-EPMC4206942 | biostudies-literature

Rhodium(III)-Catalyzed Imidoyl C-H Activation for Annulations to Azolopyrimidines.

Project description:Azolopyrimidines are efficiently prepared by direct imidoyl C-H bond activation. Annulations of N-azolo imines with sulfoxonium ylides and diazoketones under redox-neutral conditions and alkynes under oxidizing conditions provide products with various arrangements of nitrogen atoms and carbon substituents. We have also probed the mechanism of this first example of Rh(III)-catalyzed direct imidoyl C-H activation by structural characterization of a catalytically competent rhodacycle obtained after C-H activation and by kinetic isotope effects.

| S-EPMC5941131 | biostudies-literature

Rhodium(III)-Catalyzed [4+2] Annulation via C-H Activation: Synthesis of Multi-Substituted Naphthalenone Sulfoxonium Ylides.

Project description:A convenient Rh(III)-catalyzed C-H activation and cascade [4+2] annulation for the synthesis of naphthalenone sulfoxonium ylides has been developed. This method features perfect regioselectivity, mild and redox-neutral reaction conditions, and broad substrate tolerance with good to excellent yields. Preliminary mechanistic experiments were conducted and a plausible reaction mechanism was proposed. The new type naphthalenone sulfoxonium ylides could be further transformed into multi-substituted naphthols, which demonstrates the practical utility of this methodology.

| S-EPMC6572249 | biostudies-literature

Annulation of Hydrazones and Alkynes via Rhodium(III)-Catalyzed Dual C-H Activation: Synthesis of Pyrrolopyridazines and Azolopyridazines.

Project description:Hydrazones readily synthesized from N-aminopyrroles or N-aminoazoles and aldehydes undergo Rh(III)-catalyzed dual C-H activation and coupling with aryl- and alkyl-substituted alkynes to give pyrrolopyridazines or azolopyridazines, respectively. This transformation represents a rare example of hydrazoyl C-H activation and proceeds without heteroatom functionality to direct C-H activation. Hydrazones derived from aromatic, alkenyl, and aliphatic aldehydes were effective inputs, and tethering the alkyne to the hydrazone enabled annulations to more complex, tricyclic products.

| S-EPMC7007857 | biostudies-literature

Rhodium(III)-catalyzed indazole synthesis by C-H bond functionalization and cyclative capture.

Project description:An efficient, one-step, and highly functional group-compatible synthesis of substituted N-aryl-2H-indazoles is reported via the rhodium(III)-catalyzed C-H bond addition of azobenzenes to aldehydes. The regioselective coupling of unsymmetrical azobenzenes was further demonstrated and led to the development of a new removable aryl group that allows for the preparation of indazoles without N-substitution. The 2-aryl-2H-indazole products also represent a new class of readily prepared fluorophores for which initial spectroscopic characterization has been performed.

| S-EPMC3656829 | biostudies-other

Rhodium catalyzed synthesis of isoindolinones via C-H activation of N-benzoylsulfonamides.

Project description:An efficient approach to a wide range of isoindolinones, including 3-monosubstituted and 3,3-disubstituted isoindolinones, from the annulation of N-benzoylsulfonamides with olefins and diazoacetate has been developed. The transformation is broadly compatible with both terminal and internal olefins. Moreover, diazoacetate is for the first time incorporated into an amide-directed C-H functionalization reaction. Specifically, the rhodium complex [{RhCl(2)Cp*}(2)] enables the in situ dimerization of diazoacetate in addition to its role in catalyzing C-H functionalization/cross-coupling.

| S-EPMC3472453 | biostudies-literature

Rhodium(III)-catalyzed alkenyl C-H bond functionalization: convergent synthesis of furans and pyrroles.

Project description:Ring in the new: a new annulation for the efficient synthesis of substituted furans and pyrroles is reported. The Rh(III) -catalyzed reaction of O-methyl ?,?-unsaturated oximes with aldehydes and N-tosyl imines affords secondary alcohol and amine intermediates, respectively. Cyclization and aromatization occurs under the reaction conditions to provide access to biologically relevant furans and pyrroles in good yields. Cp*=C(5)Me(5), DCE=1,2-dichloroethane, THF=tetrahydrofuran.

| S-EPMC3770945 | biostudies-literature

Rhodium(I)-Complexes Catalyzed 1,4-Conjugate Addition of Arylzinc Chlorides to N-Boc-4-pyridone.

Project description:Rhodium(I)-complexes catalyzed the 1,4-conjugate addition of arylzinc chlorides to N-Boc-4-pyridone in the presence of chlorotrimethylsilane (TMSCl). A combination of [RhCl(C?H?)?]? and BINAP was determined to be the most effective catalyst to promote the 1,4-conjugate addition reactions of arylzinc chlorides to N-Boc-4-pyridone. A broad scope of arylzinc reagents with both electron-withdrawing and electron-donating substituents on the aromatic ring successfully underwent 1,4-conjugate addition to N-Boc-4-pyridone to afford versatile 1,4-adducts 2-substituted-2,3-dihydropyridones in good to excellent yields (up to 91%) and excellent ee (up to 96%) when (S)-BINAP was used as chiral ligand.

| S-EPMC6154701 | biostudies-literature

Rhodium(iii)-catalyzed synthesis of phthalides by cascade addition and cyclization of benzimidates with aldehydes.

Project description:We herein report the Rh(iii)-catalyzed C-H bond activation and addition of benzimidates to aldehydes to afford biologically important phthalides in a single step. The imidate is a novel and unexplored directing group that not only enables C-H bond activation and addition to aldehydes, but also serves to capture the reversibly formed alcohol intermediate. The reaction shows broad scope with a high level of functional group compatibility and is applicable to both aromatic and aliphatic aldehydes.

| S-EPMC3462028 | 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