Browse
Submit Data
Databases
API
Help

Dataset Information

24 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Efficient synthesis of polyfunctionalized carbazoles and pyrrolo[3,4-c]carbazoles via domino Diels-Alder reaction.

ABSTRACT: The p-TsOH-catalyzed Diels-Alder reaction of 3-(indol-3-yl)maleimides with chalcone in toluene at 60 °C afforded two diastereoisomers of tetrahydropyrrolo[3,4-c]carbazoles, which can be dehydrogenated by DDQ oxidation in acetonitrile at room temperature to give the aromatized pyrrolo[3,4-c]carbazoles in high yields. On the other hand, the one-pot reaction of 3-(indol-3-yl)-1,3-diphenylpropan-1-ones with chalcones or benzylideneacetone in acetonitrile in the presence of p-TsOH and DDQ resulted in polyfunctionalized carbazoles in satisfactory yields. The reaction mechanism included the DDQ oxidative dehydrogenation of 3-(indol-3-yl)-1,3-diphenylpropan-1-ones to the corresponding 3-vinylindoles, their acid-catalyzed Diels-Alder reaction and sequential aromatization process.

SUBMITTER: Fang RJ

PROVIDER: S-EPMC8450976 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Similar Datasets

Synthesis of Pyrrolo[1,2-a]pyrimidine Enantiomers via Domino Ring-Closure followed by Retro Diels-Alder Protocol.

Project description:From 2-aminonorbornene hydroxamic acids, a simple and efficient method for the preparation of pyrrolo[1,2-a]pyrimidine enantiomers is reported. The synthesis is based on domino ring-closure followed by microwave-induced retro Diels-Alder (RDA) protocols, where the chirality of the desired products is transferred from norbornene derivatives. The stereochemistry of the synthesized compounds was proven by X-ray crystallography. The absolute configuration of the product is determined by the configuration of the starting amino hydroxamic acid.

| S-EPMC6154686 | biostudies-literature

Orthogonal Catalysis for an Enantioselective Domino Inverse-Electron Demand Diels-Alder/Substitution Reaction.

Project description:An enantioselective domino process for the synthesis of substituted 1,2-dihydronaphthalenes has been developed by the combination of chiral amines and a bidentate Lewis acid in an orthogonal catalysis. This new method is based on an inverse electron-demand Diels-Alder and a subsequent group exchange reaction. An enamine is generated in situ from an aldehyde and a chiral secondary amine catalyst that reacts with phthalazine, activated by the coordination to a bidentate Lewis acid catalyst. The absolute configuration of the product is controlled by chiral information provided by the amine. The formed ortho-quinodimethane intermediate is then transformed via a group exchange reaction with thiols. The new method shows a broad scope and tolerates a wide range of functional groups with enantiomeric ratios up to 91 : 9. All-in-all, this enantioselective synthesis tool provides an easy access to complex 1,2-dihydronaphthalenes starting from readily available phthalazine, aldehydes and thiols in a combinatorial way.

| S-EPMC9299787 | biostudies-literature

HOAc-Mediated Domino Diels-Alder Reaction for Synthesis of Spiro[cyclohexane-1,3'-indolines] in Ionic Liquid [Bmim]Br.

Project description:An efficient and diastereoselective synthetic protocol for the construction of spiro[cyclohexane-1,3'-indolin]-3-en-2'-ones and spiro[cyclohexane-1,2'-inden]-3-ene-1',3'-diones was provided by HOAc-mediated domino reaction of pinacoles with typical dienophiles, such as 3-methyleneoxindolines and 2-arylideneindane-1,3-diones, in ionic liquid [Bmim]Br. This domino reaction involved the in situ generation of 1,3-dienes from acid-mediated dehydration of various pinacoles and the sequential Diels-Alder reaction.

| S-EPMC6641705 | biostudies-literature

The pentadehydro-Diels-Alder reaction.

Project description:In the classic Diels-Alder [4?+?2] cycloaddition reaction, the overall degree of unsaturation (or oxidation state) of the 4? (diene) and 2? (dienophile) pairs of reactants dictates the oxidation state of the newly formed six-membered carbocycle. For example, in the classic Diels-Alder reaction, butadiene and ethylene combine to produce cyclohexene. More recent developments include variants in which the number of hydrogen atoms in the reactant pair and in the resulting product is reduced by, for example, four in the tetradehydro-Diels-Alder (TDDA) and by six in the hexadehydro-Diels-Alder (HDDA) reactions. Any oxidation state higher than tetradehydro (that is, lacking more than four hydrogens) leads to the production of a reactive intermediate that is more highly oxidized than benzene. This increases the power of the overall process substantially, because trapping of the reactive intermediate can be used to increase the structural complexity of the final product in a controllable and versatile manner. Here we report an unprecedented overall 4??+?2? cycloaddition reaction that generates a different, highly reactive intermediate known as an ?,3-dehydrotoluene. This species is in the same oxidation state as a benzyne. Like benzynes, ?,3-dehydrotoluenes can be captured by various trapping agents to produce structurally diverse products that are complementary to those arising from the HDDA process. We call this new cycloisomerization process a pentadehydro-Diels-Alder (PDDA) reaction-a nomenclature chosen for chemical taxonomic reasons rather than mechanistic ones. In addition to alkynes, nitriles (RC?N), although non-participants in aza-HDDA reactions, readily function as the 2? component in PDDA cyclizations to produce, via trapping of the ?,3-(5-aza)dehydrotoluene intermediates, pyridine-containing products.

| S-EPMC4877333 | biostudies-literature

Photochemical Hexadehydro-Diels-Alder Reaction.

Project description:We demonstrate that the hexadehydro-Diels-Alder (HDDA) cycloisomerization reaction to produce reactive benzyne derivatives can be initiated photochemically. As with the thermal variant of the HDDA process, the reactive intermediates are formed in the absence of reagents or the resulting byproducts required for the generation of benzynes by traditional methods. This photo-HDDA (or hν-HDDA) reaction occurs at much lower temperatures (including even at -70 °C) than the thermal HDDA, but the benzynes produced behave in the same fashion with respect to their trapping reactions, suggesting they are of the same electronic state.

| S-EPMC6348472 | biostudies-literature

The hexadehydro-Diels-Alder reaction.

Project description:Arynes (aromatic systems containing, formally, a carbon-carbon triple bond) are among the most versatile of all reactive intermediates in organic chemistry. They can be 'trapped' to give products that are used as pharmaceuticals, agrochemicals, dyes, polymers and other fine chemicals. Here we explore a strategy that unites the de novo generation of benzynes-through a hexadehydro-Diels-Alder reaction-with their in situ elaboration into structurally complex benzenoid products. In the hexadehydro-Diels-Alder reaction, a 1,3-diyne is engaged in a [4+2] cycloisomerization with a 'diynophile' to produce the highly reactive benzyne intermediate. The reaction conditions for this simple, thermal transformation are notable for being free of metals and reagents. The subsequent and highly efficient trapping reactions increase the power of the overall process. Finally, we provide examples of how this de novo benzyne generation approach allows new modes of intrinsic reactivity to be revealed.

| S-EPMC3538845 | biostudies-literature

Versatile Dibenzothio[seleno]phenes via Hexadehydro-Diels-Alder Domino Cyclization.

Project description:A facile strategy to synthesize highly substituted dibenzoselenophenes and dibenzothiophenes by a domino hexadehydro-Diels-Alder reaction is reported in this article. The formation of three new C-C bonds, one new Caryl-Se/Caryl-S bond, and C-H ?-bond migration via one-pot multiterminal cycloaddition reactions were involved in over three transformations. The target tetracyclic compounds were prepared from tetraynes with a triphenylphosphine selenide or triphenylphosphine sulfide. This reaction played a pivotal role in constructing natural thio[seleno]phene cores, which were highly substituted, and is a robust method for producing fused heterocycles.

| S-EPMC6543197 | biostudies-literature

Diastereoselective synthesis of a spironoraristeromycin using an acylnitroso Diels-Alder reaction.

Project description:The tert-butyl N-hydroxycarbamate-derived nitroso reagent 1 reacted with N-Cbz-protected spirocyclic diene 2 to provide spirocycloadduct 3. Here we describe the efficient conversion of 3 into the novel carbocyclic nucleoside spironoraristeromycin 4.

| S-EPMC2888906 | biostudies-literature

The Aza-hexadehydro-Diels-Alder Reaction.

Project description:The generation of pyridynes from diyne nitriles is reported. These cyano-containing precursors are analogues of the triyne substrates typically used for the hexadehydro-Diels-Alder (HDDA) cycloisomerization reactions that produce ring-fused benzynes. Hence, the new processes described represent aza-HDDA reactions. Depending on the location of the nitrile, either 3,4-pyridynes (from 1,3-diynes containing a tethered cyano group) or 2,3-pyridynes (from 1-cyanoethyne derivatives containing a tethered alkyne) are produced. In situ trapping of these reactive intermediates leads to highly substituted and functionalized pyridine derivatives. In several instances, unprecedented pyridyne trapping reactions are seen. Differences in reaction energetics between the aza-HDDA substrates and that of their analogous HDDA (triyne) substrates are discussed.

| S-EPMC6921493 | biostudies-literature

An on-surface Diels-Alder reaction.

Project description:The Diels-Alder reaction is one of the most popular reactions in organic chemistry. However, its use in the field of on-surface synthesis is hampered by the spatial restrictions of this cycloaddition reaction. Herein we selected a cyclic strained triyne to demonstrate an on-surface hexadehydro-Diels-Alder reaction in a single molecule. The reaction was studied in detail by means of atomic force microscopy (AFM) with CO-functionalized tips. Our results pave the way to use this iconic pericyclic reaction for on-surface synthesis, introducing the concept of atom economy in the field.

| S-EPMC9298865 | 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