Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Environmentally Benign Lewis Acid Promoted [2+3]-Dipolar Cycloaddition Reactions of Nitrile Imines with Alkenes in Water.

ABSTRACT: Mild and environmentally benign Lewis acid promoted 1,3-dipolar cycloaddition reactions of ?-hydrazonyl chlorides with alkenes in water are reported. These ?-hydrazonyl chlorides, in the presence of Lewis acids, generate nitrile imines in situ which react with dipolarophiles to furnish the corresponding cycloaddition products. In many cases, the required times for the completion of the Lewis acid promoted 1,3-dipolar cycloaddition reactions in water were comparable to the equivalent reactions performed in an organic solvent. Analogous tetrahexylammonium chloride promoted 1,3-dipolar cycloaddition reactions were also performed. The comparison of reaction times and cycloadduct yields for the aforementioned 1,3-dipolar reactions in aqueous and organic media as well as the proposed role of the Lewis acid in the 1,3-dipolar cycloaddition reaction are described.

SUBMITTER: Dadiboyena S

PROVIDER: S-EPMC3957226 | biostudies-literature | 2013 Nov

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

Environmentally Benign Lewis Acid Promoted [2+3]-Dipolar Cycloaddition Reactions of Nitrile Imines with Alkenes in Water.

Dadiboyena Sureshbabu S Hamme Ashton T AT

European journal of organic chemistry 20131101 33

Mild and environmentally benign Lewis acid promoted 1,3-dipolar cycloaddition reactions of α-hydrazonyl chlorides with alkenes in water are reported. These α-hydrazonyl chlorides, in the presence of Lewis acids, generate nitrile imines <i>in situ</i> which react with dipolarophiles to furnish the corresponding cycloaddition products. In many cases, the required times for the completion of the Lewis acid promoted 1,3-dipolar cycloaddition reactions in water were comparable to the equivalent react ...[more]

PMID: 24659908

Similar Datasets

Stereoselective Lewis base catalyzed formal 1,3-dipolar cycloaddition of azomethine imines with mixed anhydrides.

Project description:Stereoselective synthesis of pyrazolidinones via dipolar cycloaddition of azomethine imines with active esters under Lewis base catalysis is presented. The active esters are readily generated in situ from the corresponding acids. Products, which are obtained with excellent diastereocontrol and high enantioselectivity, contain along with the pyrazolidinone core also the tetrahydroisoquinoline structural motif. Theoretical studies give insight into the mechanism of the formal cycloaddition reaction.

| S-EPMC5811128 | biostudies-other

Stereocontrolled synthesis of functionalized cis-cyclopentapyrazolidines by 1,3-dipolar cycloaddition reactions of azomethine imines.

Project description:The reaction of alkene-tethered alpha-ketocarboxylic acid derivatives with monosubstituted hydrazines allows highly substituted cis-cyclopentapyrazolidine ring systems to be constructed rapidly. Successful cyclocondensations are realized under thermal reaction conditions; in some cases, protic or Lewis acids accelerate these reactions. alpha-Methoxy-alpha,beta-unsaturated esters are suitable alkene components, as are alkenes having either electron-withdrawing or electron-donating substituents at the terminal alkene carbon. alpha-Ketoesters, alpha-ketoamides, and alpha-ketothioesters can be employed. Various hydrazines substituted with N-acyl, N-carboalkoxy, or N-carbamothioyl protecting groups are tolerated in these transformations. The rate of intramolecular cycloaddition is found to reflect not only the reactivity and equilibrium concentration of the azomethine imine intermediate, but, also in some cases, the rate at which hydrazone stereoisomers interconvert under the reaction conditions.

| S-EPMC2516743 | biostudies-literature

Catalytic, enantioselective 1,3-dipolar cycloadditions of nitrile imines with methyleneindolinones.

Project description:Catalytic, enantioselective 1,3-dipolar cycloadditions of nitrile imines with methyleneindolinones are reported. The spiro[pyrazolin-3,3'-oxindole] products are formed in good yields (up to 98%) and high enantioselectivity (up to 99% ee).

| S-EPMC3876797 | biostudies-literature

Isoxazolodihydropyridinones: 1,3-dipolar cycloaddition of nitrile oxides onto 2,4-dioxopiperidines.

Project description:Practical and efficient methods have been developed for the diversity-oriented synthesis of isoxazolodihydropyridinones via the 1,3-dipolar cycloaddition of nitrile oxides onto 2,4-dioxopiperidines. A select few of these isoxazolodihydropyridinones were further elaborated with triazoles by copper-catalyzed azide-alkyne cycloaddition reactions. A total of 70 compounds and intermediates were synthesized and analyzed for drug likeness. Sixty-four of these novel compounds were submitted to the NIH Molecular Libraries Small Molecule Repository for high-throughput biological screening.

| S-EPMC3345193 | biostudies-literature

Formal [3+2] Cycloaddition Reactions of Electron-Rich Aryl Epoxides with Alkenes under Lewis Acid Catalysis Affording Tetrasubstituted Tetrahydrofurans.

Project description:We report on the regio- and stereoselective synthesis of tetrahydrofurans by reaction between epoxides and alkenes in the presence of a Lewis acid. This is an unprecedented formal [3+2] cycloaddition reaction between an epoxide and an alkene. The chemical reaction represents a very concise synthesis of tetrahydrofurans from accessible starting compounds.

| S-EPMC7036929 | biostudies-literature

Cyaphide-Azide 1,3-Dipolar Cycloaddition Reactions: Scope and Applicability.

Project description:Several examples of the cyaphide-azide 1,3-dipolar cycloaddition reaction to afford metallo-triazaphospholes are reported. The gold(I) triazaphospholes Au(IDipp)(CPN3 R) (IDipp=1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene; R=t Bu, Ad, Dipp), magnesium(II) triazaphospholes, {Mg(Dipp NacNac)(CPN3 R)}2 (Dipp NacNac=CH{C(CH3 )N(Dipp)}2 , Dipp=2,6-diisopropylphenyl; R=t Bu, Bn), and germanium(II) triazaphosphole Ge(Dipp NacNac)-(CPN3 t Bu) can be prepared straightforwardly, under mild conditions and in good yields, in a manner reminiscent of the classic alkyne-azide click reaction (albeit without a catalyst). This reactivity can be extended to compounds with two azide functional groups such as 1,3-diazidobenzene. It is shown that the resulting metallo-triazaphospholes can be used as precursors to carbon-functionalized species, including protio- and iodo-triazaphospholes.

| S-EPMC10946888 | biostudies-literature

Environmentally Benign, Base-Promoted Selective Amination of Polyhalogenated Pyridines.

Project description:An environmentally benign, highly efficient, and base-promoted selective amination of various polyhalogenated pyridines including the challenging pyridine chlorides to 2-aminopyridine derivatives using water as solvent has been developed. Featuring the use of the new method, the reaction is extended to the transformation on a large scale. Mechanistic studies indicate that the pathway involving a base aidant dissociation of N,N-dimethylformamide to generate dimethylamine is likely.

| S-EPMC6648585 | biostudies-literature

Bioorthogonal prodrug activation driven by a strain-promoted 1,3-dipolar cycloaddition.

Project description:Due to the formation of hydrolysis-susceptible adducts, the 1,3-dipolar cycloaddition between an azide and strained trans-cyclooctene (TCO) has been disregarded in the field of bioorthogonal chemistry. We report a method which uses the instability of the adducts to our advantage in a prodrug activation strategy. The reaction of trans-cyclooctenol (TCO-OH) with a model prodrug resulted in a rapid 1,3-dipolar cycloaddition with second-order rates of 0.017 M-1 s-1 and 0.027 M-1 s-1 for the equatorial and axial isomers, respectively, resulting in release of the active compound. 1H NMR studies showed that activation proceeded via a triazoline and imine, both of which are rapidly hydrolyzed to release the model drug. Cytotoxicity of a doxorubicin prodrug was restored in vitro upon activation with TCO-OH, while with cis-cyclooctenol (CCO-OH) no activation was observed. The data also demonstrates the potential of this reaction in organic synthesis as a mild orthogonal protecting group strategy for amino and hydroxyl groups.

| S-EPMC5811098 | biostudies-literature

Synthesis of trifluoromethylated isoxazolidines: 1,3-dipolar cycloaddition of nitrosoarenes, (trifluoromethyl)diazomethane, and alkenes.

Project description:Isoxazolidines have proven to be important substrates in synthetic organic chemistry. Limited examples in the literature that provide trifluoromethylated versions of these compounds have prompted us to investigate a 1,3-dipolar cycloaddition route providing access to N-functionalized isoxazolidines containing a trifluoromethyl group. Thus, a 1,3-dipolar cycloaddition of nitrosoarenes, (trifluoromethyl)diazomethane, and alkenes was developed. The starting materials can be synthesized from easy to handle and accessible reagents. The reaction proved to be tolerant of a variety of electron-deficient alkenes and nitrosoarenes.

| S-EPMC3914015 | biostudies-literature

Lewis acid-promoted [2 + 2] cycloadditions of alkenes with aryl ketenes.

Project description:A method for the [2 + 2] cycloaddition of aryl ketenes and alkenes is presented. The process involves the in situ generation of a ketene in the presence of a Lewis acid. The utility of products is demonstrated towards the synthesis of a common scaffold found in several natural product families.

| S-EPMC4814371 | 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