Synthesis Of Substituted Indoles Research Articles

Synthesis of 2-Substituted Indoles via Migration Reaction of 3-Substituted Indoles with Triflic Acid.

This study showcases the 1,2-migration reactions of alkyl and aryl groups on the indole molecule. Trifluoromethanesulfonic acid effectively facilitates the migration of the substituent from C3- to C2-position of the indole structure. The resulting C2-substituted indoles offer a valuable pathway for the synthesis of natural products and medicinal compounds.

NiO@TPP-HPA as an Efficient Integrated Nanocatalyst and Anti-Liver Cancer Agent. Synthesis of 2-Substituted Indoles

A new tetraphenylporphyrin-heteropolyacid (TPP-HPA) nanohybrid material is synthesized and loaded onto NiO nanoparticles to achieve an efficient heterogeneous catalyst. Then, the new inorganic-organic nanohybrid catalyst NiO@TPP-HPA was introduced as an efficient and recoverable catalyst in the synthesis of 2-substituted indoles through condensation of indole with malononitrile and different aldehydes at solventless condition. The nanohybrid material was characterized by FESEM, EDS, XRD, FTIR and TGA. The attained findings showed that NiO@TPP-HPA is an effective catalyst toward the desired condensation reaction and provided good recyclability for at least six runs without significant loss of activity. Moreover, it has been shown that preparation of 2-substituted indoles occurs by the way of radical mechanism, indicating •O2 −, h+ and OH• as contributing species. In addition, the hot-filtration experiment proved that NiO@TPP-HPA is a steady nanocatalyst in the current multicomponent synthesis. Moreover, the in-vitro toxicity of NiO@TPP-HPA was inspected toward HepG2 cell line through an MTT assay, confirming that this nanomaterial is a potential agent against the desired cell line. Therefore, this nanocomposite can be treated as an anti-liver cancer agent.

Synthesis of 2-substituted indoles and evaluation of their antibacterial activity and inhibitory effects on the efflux pump of methicillin-resistant Staphylococcus aureus

Synthesis and Antimicrobial studies of novel Benzimidazole derivativesParmender Singh Rathee,Ritu Dhankar, Sunny Bhardwaj,Monika Gupta, Rakesh Kumar

Polyethylene Glycol (PEG-400): A Green Reaction Medium for One-Pot, Three Component Synthesis of 3-Substituted Indoles under Catalyst Free Conditions

A catalyst-free, cost-effective and environmentally friendly protocol for the synthesis of 3-substituted indoles via a one-pot multicomponent condensation reaction of indole, C–H activated acids and aromatic aldehydes in polyethylene glycol 400 (PEG-400) as a reaction medium and reaction promoter has been developed. The most important feature of this protocol is selectivity in the formation of heterodimer products instead of homodimer adducts such as bisindole or xanthine.

Synthesis of 2-substituted indoles through cyclization and demethylation of 2-alkynyldimethylanilines by ethanol

EtOH is an ideal reagent for transforming 2-alkynyldimethylanilines into 2-substituted indoles with high yields without the need for metal catalysts or additives.

Hypervalent Iodine Reagent for the Synthesis of 2-Substituted Indoles

Hypervalent Iodine Reagent for the Synthesis of 2-Substituted Indoles

One-pot sequential multi-component reaction: Synthesis of 3-substituted indoles

Here, we have developed a 3-component one-pot sequential approach to 3-substituted indoles. The main advantages of this process are step economy, reduced waste, and operational simplicity. The method involves in situ generation of 3-indolylalcohols from the reaction of indoles and aldehydes in the presence of base. Further, nucleophilic substitution of 3-indolylalcohols with various nucleophiles affords 3-substituted indole derivatives. The reaction does not requires any hazardous and expensive metal catalyst. In addition, the reaction is carried out in (1:1) ethanol–water which is considered as environmentally benign solvent. On the other hand, nonsequential 3-component reaction results in the formation of unwanted bisindolylmethanes.

Iron(III) Chloride Hexahydrate Catalysed Efficient Synthesis of 3-substituted Indoles Via Micheal Addition Reaction

Iron(III) Chloride Hexahydrate Catalysed Efficient Synthesis of 3-substituted Indoles Via Micheal Addition Reaction

Synthesis of 3-Substituted Indoles Using a Silica-Supported Vanadium Catalyst

Synthesis of 3-Substituted Indoles Using a Silica-Supported Vanadium Catalyst

Ruthenium-Catalyzed Cycloisomerization of 2-Alkynylanilides: Synthesis of 3-Substituted Indoles by 1,2-Carbon Migration.

We developed ruthenium-catalyzed cycloisomerization of alkynylanilides that gave 3-substituted indoles in high yields. The reaction proceeded via the disubstituted vinylidene ruthenium complex that was formed by the 1,2-carbon migration.

1603899: Efficient synthesis of 3-substituted indoles via a base-free copper-catalysed three-component reaction in water – ESI

1603899: Efficient synthesis of 3-substituted indoles <i>via</i> a base-free copper-catalysed three-component reaction in water – ESI

ChemInform Abstract: Synthesis of Indoles, Benzofurans, and Related Heterocycles via an Acetylene‐Activated SNAr/Intramolecular Cyclization Cascade Sequence in Water or DMSO.

The synthesis of 2-substituted indoles and benzofurans was achieved by nucleophilic aromatic substitution, followed by subsequent 5-endo-dig cyclization between the nucleophile and an ortho acetylene. The acetylene serves the dual role of the electron withdrawing group to activate the substrate for SNAr, and the C1–C2 carbon scaffold for the newly formed 5-membered heteroaromatic ring. This method allows for the bond forming sequence of Ar–X–N/O–C1 to proceed in a single synthetic step, furnishing indoles and benzofurans in moderate to high yields. Since the method is not transition metal mediated, brominated and chlorinated substrates are tolerated, and benzofuran formation can be conducted using water or water–DMSO mixtures as solvent.

Synthesis of indoles, benzofurans, and related heterocycles via an acetylene-activated SNAr/intramolecular cyclization cascade sequence in water or DMSO.

The synthesis of 2-substituted indoles and benzofurans was achieved by nucleophilic aromatic substitution, followed by subsequent 5-endo-dig cyclization between the nucleophile and an ortho acetylene. The acetylene serves the dual role of the electron withdrawing group to activate the substrate for SNAr, and the C1-C2 carbon scaffold for the newly formed 5-membered heteroaromatic ring. This method allows for the bond forming sequence of Ar-X-N/O-C1 to proceed in a single synthetic step, furnishing indoles and benzofurans in moderate to high yields. Since the method is not transition metal mediated, brominated and chlorinated substrates are tolerated, and benzofuran formation can be conducted using water or water-DMSO mixtures as solvent.

Synthesis of 3-substituted indole by AlCl3-promoted reaction of β,γ-unsaturated ketone with indole

A one-pot Lewis acid-promoted reaction condition of β,γ-unsaturated ketone with indole was developed for the synthesis of 3-substituted indoles with moderate to good yields. A Lewis acid such as AlCl3 was shown to be a promising promoter for in situ isomerization of β,γ-unsaturated ketone to its corresponding α,β-unsaturated ketone, then undergoing Friedel–Crafts Michael addition reaction with indole to afford 3-substituted indole.

3-Chlorophenylboronic acid-promoted, one-pot, aza-Friedel–Crafts reaction of indoles

3-Chlorophenylboronic acid promotes efficient synthesis of 3-substituted indole derivatives via aza-Friedel–Crafts reaction of indoles, aromatic aldehydes, and N,N-dimethylaniline at room temperature. The mild reaction conditions, excellent yields, and easy experimental workup are striking features of this procedure for synthesis of 3-substituted indoles.

ChemInform Abstract: Pd‐Catalyzed Cascade Reaction for the Synthesis of 2‐Substituted Indoles.

AbstractCross‐coupling of nitrobenzyl cyanides with boronic acids affords 2‐substituted indoles.

ChemInform Abstract: The Chemistry of Indoles. Part 60. A Regioselective Lithiation of 1- Methoxymethoxyindole at the 2-Position and Its Application for the Synthesis of 2-Substituted Indoles.

ChemInform Abstract: The Chemistry of Indoles. Part 60. A Regioselective Lithiation of 1- Methoxymethoxyindole at the 2-Position and Its Application for the Synthesis of 2-Substituted Indoles.

Synthesis of 2-substituted indoles via a palladium-catalyzed domino Heck reaction and dealkylation

Abstract A palladium-catalyzed domino Heck reaction and dealkylation for the preparation of 2-substituted indoles is described. This novel transformation is based on an intramolecular Heck reaction followed by dealkylation.

Synthesis of 3-substituted indoles via reactive alkylideneindolenine intermediates

Elimination of suitable leaving groups from 3-substituted indoles under basic or acidic conditions readily provides alkylideneindolenine intermediates that may react with a large variety of nucleophilic reagents. This article highlights some recent developments of this synthetic approach for the preparation of functionalized indole derivatives.

Ligand‐, Copper‐, and Amine‐Free One‐Pot Synthesis of 2‐Substituted Indoles via Sonogashira Coupling 5‐endo‐dig Cyclization.

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