Browse
Submit Data
Databases
API
Help

Dataset Information

30 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Room temperature copper(II)-catalyzed oxidative cyclization of enamides to 2,5-disubstituted oxazoles via vinylic C-H functionalization.

ABSTRACT: A copper(II)-catalyzed oxidative cyclization of enamides to oxazoles via vinylic C-H bond functionalization at room temperature is described. Various 2,5-disubstituted oxazoles bearing aryl, vinyl, alkyl, and heteroaryl substituents could be synthesized in moderate to high yields. This reaction protocol is complementary to our previously reported iodine-mediated cyclization of enamides to afford 2,4,5-trisubstituted oxazoles.

SUBMITTER: Cheung CW

PROVIDER: S-EPMC3454444 | biostudies-literature | 2012 Sep

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

Room temperature copper(II)-catalyzed oxidative cyclization of enamides to 2,5-disubstituted oxazoles via vinylic C-H functionalization.

Cheung Chi Wai CW Buchwald Stephen L SL

The Journal of organic chemistry 20120813 17

A copper(II)-catalyzed oxidative cyclization of enamides to oxazoles via vinylic C-H bond functionalization at room temperature is described. Various 2,5-disubstituted oxazoles bearing aryl, vinyl, alkyl, and heteroaryl substituents could be synthesized in moderate to high yields. This reaction protocol is complementary to our previously reported iodine-mediated cyclization of enamides to afford 2,4,5-trisubstituted oxazoles. ...[more]

PMID: 22838632

Similar Datasets

General methodology for the preparation of 2,5-disubstituted-1,3-oxazoles.

Project description:Deprotonation of 2-(phenylsulfonyl)-1,3-oxazole (1) readily provides a useful C-5 carbanion that is reactive with a variety of electrophiles. Aldehydes and ketones are useful substrates, and the formation of 5-iodo- and 5-tri-n-butylstannyl oxazoles affords access to cross-coupling reactions. Subsequent nucleophilic displacement of the 2-phenylsulfonyl group provides a general route for the synthesis of 2,5-disubstituted-1,3-oxazoles.

| S-EPMC3566646 | biostudies-literature

Copper-Catalyzed Dimerization/Cyclization of Itaconates.

Project description:A copper-catalyzed domino reaction between itaconate esters and diethyl zinc (or silane) is developed, affording itaconate dimerization products, multi-ester-substituted cyclopentanones, in moderate to high yields.

| S-EPMC6332366 | biostudies-literature

Iodine-Catalyzed Functionalization of Primary Aliphatic Amines to Oxazoles, 1,4-Oxazines, and Oxazinones.

Project description:Unprecedented I2-catalyzed ?,?-C(sp3)-H, decarboxylative ?-C(sp3)-H, lactonized ?-C(sp3)-H, and ?,?-C(sp3)-H functionalized 5- and 6-annulation as well as ?-C(sp3)-H activated 6-lactonization of primary aliphatic amines are devised under aerobic conditions. The metal-free sustainable strategy was employed for the diverse construction of valuable five-and six-membered polycyclic N,O-heteroaromatics such as oxazoles, 1,4-oxazines, and oxazin-2-one with a rapid reaction rate and high yield. The viability of this mild nonmetallic catalysis is successfully verified through syntheses of labile chiral heterocyclic analogues. In contrast to the common practice, this method is not limited to use of prefunctionalized amines, directing groups (DGs) and/or transient DGs, metal catalysts, and traditional oxidants. The possible mechanistic pathway of the annulation reaction is investigated by control experiments and ESI-MS data collected for a reaction mixture of the ongoing reaction. The synthesized new compounds are potent organic nanobuilding blocks to achieve valuable organic nanomaterials of different sizes, shapes, and dimensions, which are under investigation for the discovery of high-tech devices of innovative organic nanoelectronics and photophysical properties.

| S-EPMC6894181 | biostudies-literature

Diastereo- and enantioselective copper catalyzed hydroallylation of disubstituted cyclopropenes.

Project description:A highly diastereo- and enantioselective protocol for the hydroallylation of 1,1- and 1,2-disubstituted cyclopropenes has been developed utilizing an in situ formed copper hydride. A variety of allyl electrophiles could be utilized yielding a diverse range of trisubstituted cyclopropanes. Finally a preliminary enantioselective variant could be established employing a recently described P-stereogenic xantphos derivative as ligand.

| S-EPMC6115688 | biostudies-other

Copper-Catalyzed One-Pot Synthesis of 2,5-Disubstituted 1,3,4-Oxadiazoles from Arylacetic Acids and Hydrazides <i>via</i> Dual Oxidation.

Project description:A simple and efficient protocol has been developed to access symmetrical and unsymmetrical 2,5-disubstituted 1,3,4-oxadiazoles from arylacetic acids and hydrazides via copper-catalyzed dual oxidation under an oxygen atmosphere. Oxidative decarboxylation of arylacetic acids and oxidative functionalization of the imine C-H bond are the key steps. This is the first example of the synthesis of 2,5-disubstituted 1,3,4-oxadiazoles through dual oxidation in one-pot. Avoidance of the expensive ligand and high yield of the products are advantageous features of the developed method.

| S-EPMC9366783 | biostudies-literature

Sustainable Access to 5-Amino-Oxazoles and Thiazoles via Calcium-Catalyzed Elimination-Cyclization with Isocyanides.

Project description:Herein, we report a sustainable, modular, rapid and high-yielding transformation to afford densely functionalized 5-aminooxazoles and thiazoles. The reaction is tolerant to a wide range of functional groups and is typically complete in under 30 min. Furthermore, the described transformation is inherently green in relation to the catalyst and solvent choice as well as producing environmentally benign alcoholic by-products.

| S-EPMC8048476 | biostudies-literature

Catalyst-Free Visible-Light-Promoted Cyclization of Aldehydes: Access to 2,5-Disubstituted 1,3,4-Oxadiazole Derivatives.

Project description:An efficient synthesis of a variety of 2,5-disubstituted 1,3,4-oxadiazole derivatives via a cyclization reaction by photoredox catalysis between aldehydes and hypervalent iodine(III) reagents is described. The reaction proceeds under mild conditions and affords various target compounds in excellent yields. The commercially available aldehydes without preactivation and a simple visible-light-promoted procedure without any catalysts make this strategy an alternative to the conventional methods.

| S-EPMC8515816 | biostudies-literature

Copper-catalyzed synthesis of 2,4-disubstituted allenoates from ?-diazoesters.

Project description:A Cu-catalyzed method for coupling ?-substituted-?-diazoesters with terminal alkynes to give substituted allenoates is described. Key to the development of a selective method was the recognition that an adventitous base catalyzes the isomerization to form the allenoate product. A plausible mechanism is proposed, based in part on evidence against a mechanism that involves a Cu(I)-acetylide as a low-valent intermediate.

| S-EPMC3128944 | biostudies-literature

Gold-catalyzed tandem reactions of amide-aldehyde-alkyne coupling and cyclization-synthesis of 2,4,5-trisubstituted oxazoles.

Project description:We report the first cationic gold(i)-catalyzed one-pot reaction of amide, alkyne and aldehyde followed by cyclization, to successfully access highly substituted oxazoles derivatives in good yields. A single catalyst allows the occurring of this multi-step reaction atom- and step-economically, with water as the only theoretical side product.

| S-EPMC5950834 | biostudies-other

Copper-Catalyzed Dual Cyclization for the Synthesis of Quinindolines.

Project description:A synthetic approach to quinindoline derivatives by the Cu-catalyzed dual cyclization has been developed. This catalytic reaction is a practical method for the systematic synthesis of quinindoline core structure, which contains a limited-step synthetic strategy and can tolerant a wide variety of substituents. In addition, the mechanistic study reveals that the reaction initiates from a Lewis acid accelerated addition of aniline to nitrile and provides the indole substructure, and then the subsequent Cu-catalyzed C-N coupling reaction furnishes the quinoline subunit and affords the quinindoline structure.

| S-EPMC7696892 | 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