Browse
Submit Data
Databases
API
Help

Dataset Information

35 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Asymmetric Cu-Catalyzed 1,4-Dearomatization of Pyridines and Pyridazines without Preactivation of the Heterocycle or Nucleophile.

ABSTRACT: We show that a chiral copper hydride (CuH) complex catalyzes C-C bond-forming dearomatization of pyridines and pyridazines at room temperature. The catalytic reaction operates directly on free heterocycles and generates the nucleophiles in situ, eliminating the need for stoichiometric preactivation of either reaction partner; further, it is one of very few methods available for the enantioselective 1,4-dearomatization of heteroarenes. Combining the dearomatization with facile derivatization steps enables one-pot syntheses of enantioenriched pyridines and piperidines.

SUBMITTER: Gribble MW

PROVIDER: S-EPMC5929106 | biostudies-literature | 2018 Apr

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

Asymmetric Cu-Catalyzed 1,4-Dearomatization of Pyridines and Pyridazines without Preactivation of the Heterocycle or Nucleophile.

Gribble Michael W MW Guo Sheng S Buchwald Stephen L SL

Journal of the American Chemical Society 20180406 15

We show that a chiral copper hydride (CuH) complex catalyzes C-C bond-forming dearomatization of pyridines and pyridazines at room temperature. The catalytic reaction operates directly on free heterocycles and generates the nucleophiles in situ, eliminating the need for stoichiometric preactivation of either reaction partner; further, it is one of very few methods available for the enantioselective 1,4-dearomatization of heteroarenes. Combining the dearomatization with facile derivatization step ...[more]

PMID: 29609461

Similar Datasets

Evidence for Simultaneous Dearomatization of Two Aromatic Rings under Mild Conditions in Cu(I)-Catalyzed Direct Asymmetric Dearomatization of Pyridine.

Project description:Bis(phosphine) copper hydride complexes are uniquely able to catalyze direct dearomatization of unactivated pyridines with carbon nucleophiles, but the mechanistic basis for this result has been unclear. Here we show that, contrary to our initial hypotheses, the catalytic mechanism is monometallic and proceeds via dearomative rearrangement of the phenethylcopper nucleophile to a Cpara-metalated form prior to reaction at heterocycle C4. Our studies support an unexpected heterocycle-promoted pathway for this net 1,5-Cu-migration beginning with a doubly dearomative imidoyl-Cu-ene reaction. Kinetics, substituent effects, computational modeling, and spectroscopic studies support the involvement of this unusual process. In this pathway, the CuL2 fragment subsequently mediates a stepwise Cope rearrangement of the doubly dearomatized intermediate to the give the C4-functionalized 1,4-dihydropyridine, lowering a second barrier that would otherwise prohibit efficient asymmetric catalysis.

| S-EPMC8171382 | biostudies-literature

Palladium-catalyzed asymmetric dearomatization of naphthalene derivatives.

Project description:An intramolecular enantioselective metal-catalyzed dearomatization reaction is described. This procedure allows the dearomatization of naphthalene derivatives through an electrophilic aromatic substitution-type reaction on a Pd(II) intermediate. The high yields and enantioselectivities achieved make this procedure a valuable method for synthetic chemists.

| S-EPMC2748791 | biostudies-literature

Halogenated salt assisted Cu-catalyzed asymmetric 1,4-borylstannation of 1,3-enynes: enantioselective synthesis of allenylstannes.

Project description:An enantioselective 1,4-borylstannation of 1,3-enynes employed a chiral sulfoxide phosphine (SOP)/Cu complex as a catalyst, and the desired products, chiral allenylstannes, were first synthesized by asymmetric catalysis with satisfactory yields and enantioselectivies. In this protocol, a catalytic amount of additive, a halogenated salt, plays a crucial role in the success. Control experiments and theoretical studies disclosed that the four-membered ring transmetallation transition states which were stabilized by a halide anion are the key to yields and stereochemical outcomes.

| S-EPMC8179376 | biostudies-literature

Substituted Dihydropyridine Synthesis by Dearomatization of Pyridines.

Project description:Dearomatization is an effective method to transform readily available N-heterocycles into partially saturated motifs. Manipulation of dihydro-derivatives holds great potential and provides access to a variety of semi-saturated N-heterocyclic building blocks. However, current strategies are limited in scope and the use of sensitive reagents restricts the applicability in synthetic laboratories. Herein, we report the synthesis of a broad variety of N-substituted 1,4- and 1,2-dihydropyridines by very mild and selective reduction with amine borane for the first time.

| S-EPMC8252501 | biostudies-literature

Cu(I)-catalyzed asymmetric diamination of conjugated dienes.

Project description:A Cu(I)-catalyzed asymmetric diamination for a variety of conjugated dienes and a triene with encouraging ee's has been effectively achieved using (R)-DTBM-SEGPHOS as a chiral ligand and di- tert-butyldiaziridinone as the nitrogen source.

| S-EPMC2659555 | biostudies-other

Asymmetric Synthesis of Flavanols via Cu-Catalyzed Kinetic Resolution of Chromenes and Their Anti-Inflammatory Activity

Project description:We report a highly efficient kinetic resolution of chromenes for the first time via a Cu-catalyzed asymmetric hydroboration. This novel approach features simple one-pot synthesis of chiral flavan-3-ols containing two vicinal stereogenic centers via a highly efficient kinetic resolution pathway (s factor up to 1060, >99% ee for most substrates and products, exclusively trans products). In addition, the anti-inflammation effects of these diversified flavan-3-ols have been further studied by the in vitro experiments and RNA-sequencing (RNA-seq) analysis. The modified flavan-3-ol natural product derivatives showed inhibitory effects on the expression and secretion of pro-inflammation cytokines including IL-1β, IL-6 and TNF-α, as well as inhibiting the inflammation responses through downregulating the gene transcriptions closely related to IL-17 signaling pathway, PI3K-Akt signaling pathway and TNF signaling pathway, which suggest these newly synthesized compounds are potent lead compounds for treating inflammation diseases.

2021-07-30 | GSE181052 | GEO

Bronsted acid-catalyzed asymmetric dearomatization for synthesis of chiral fused polycyclic enone and indoline scaffolds.

Project description:In the past two decades, substantial advances have been made on the asymmetric alkyne functionalization by the activation of inert alkynes. However, these asymmetric transformations have so far been mostly limited to transition metal catalysis, and chiral Brønsted acid-catalyzed examples are rarely explored. Here, we report a chiral Brønsted acid-catalyzed dearomatization reaction of phenol- and indole-tethered homopropargyl amines, allowing the practical and atom-economical synthesis of a diverse array of valuable fused polycyclic enones and indolines bearing a chiral quaternary carbon stereocenter and two contiguous stereogenic centers in moderate to good yields with excellent diastereoselectivities and generally excellent enantioselectivities (up to >99% enantiomeric excess). This protocol demonstrates Brønsted acid-catalyzed asymmetric dearomatizations via vinylidene-quinone methides.

| S-EPMC10017053 | biostudies-literature

Organocatalytic asymmetric chlorinative dearomatization of naphthols.

Project description:An organocatalytic asymmetric chlorinative dearomatization of naphthols was realized for the first time, providing chiral naphthalenones with a Cl-containing all-substituted stereocenter in excellent yields and enantioselectivity (up to 97% yield and 96% ee). The reaction features mild reaction conditions, good tolerance of diverse functional groups and simple reaction operation.

| S-EPMC5707459 | biostudies-literature

Palladium-Catalyzed Decarboxylative Asymmetric Allylic Alkylation of 1,4-Diazepan-5-ones.

Project description:We report the palladium-catalyzed asymmetric allylic alkylation of 1,4-diazepan-5-ones. This reaction proceeds smoothly to give gem-disubstituted diazepanone heterocycles bearing various functional groups in up to >99% yield and up to 95% ee. An electron-rich p-anisoyl lactam protecting group and the use of a nonpolar solvent proved crucial to obtaining high enantioselectivity in most cases. Additionally, we demonstrate the use of our methodology in the synthesis of a gem-disubstituted analogue of the FDA-approved anti-insomnia drug suvorexant.

| S-EPMC8579948 | biostudies-literature

Synthesis and Facile Dearomatization of Highly Electrophilic Nitroisoxazolo[4,3-b]pyridines.

Project description:A number of novel 6-R-isoxazolo[4,3-b]pyridines were synthesized and their reactions with neutral C-nucleophiles (1,3-dicarbonyl compounds, π-excessive (het)arenes, dienes) were studied. The reaction rate was found to be dependent on the nature of the substituent 6-R. The most reactive 6-nitroisoxazolo[4,3-b]pyridines are able to add C-nucleophiles in the absence of a base under mild conditions. In addition, these compounds readily undergo [4+2]-cycloaddition reactions on aromatic bonds C=C(NO2) of the pyridine ring, thus indicating the superelectrophilic nature of 6-NO2-isoxazolo[4,3-b]pyridines.

| S-EPMC7248838 | 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