104142-15-6

Upstream product

• 104142-24-7 3-acetyl-N-(p-toluenesulfonyl)indole 
• 5416-80-8 2-methyl-1H-indole-3-carbaldehyde 
• 104-15-4 toluene-4-sulfonic acid 
• 95-20-5 2-methyl-1H-indole 
• 98-59-9 p-toluenesulfonyl chloride 

Downstream Products

• 104142-24-7 3-acetyl-N-(p-toluenesulfonyl)indole 

Relevant academic research and scientific papers

Direct construction of carbazoles from 2-methyl-indole-3-carbaldehydes and enals

The direct and rapid construction of carbazoles was achieved via the reaction of 2-methyl-indole-3-carbaldehydes with enals promoted by LiCl/DBU in a single operation. This mild and green reaction proceeds through a [4 + 2] cycloaddition/dehydration/oxidative aromatization cascade to generate carbazoles in good to excellent yields. The reaction features mild reaction conditions, a broad substrate scope, and excellent functional group tolerance, using O2 (1 atm) as the sole oxidant and affording H2O as the only by-product. More importantly, 4-fluoroquinocarbazole, a significant bioactive compound, was generated in 80% yield in only one step from the obtained carbazole.

Exploiting the Distal Reactivity of Indolyl Methylenemalononitriles: An Asymmetric Organocatalyzed [4+2] Cycloaddition with Enals Enables the Assembly of Elusive Dihydrocarbazoles

An unprecedented technique for the in situ generation of indolyl ortho-quinodimethanes from 2-methylindole-based methylenemalononitriles by amine-mediated remote C(sp3)?H deprotonation was developed. These intermediates were efficiently trapped by diverse enals to provide a rapid entry to 2,9-dihydro-1H-carbazole-3-carboxyaldehyde structures through a formal asymmetric [4+2] eliminative cycloaddition governed by a α,α-diphenylprolinol trimethylsilyl ether catalyst.

Palladium-catalysed annulative allylic alkylation for the synthesis of benzannulated heteroarenes

A conceptually novel intramolecular allylic alkylation strategy is developed for the synthesis of carbazoles and dibenzothiophenes. In an unusual event, palladium catalyses the formation of π-allylpalladium complexes of the respective (2-methylindol-3-yl)allyl acetates and subsequently facilitates the benzannulation process. This journal is

Br?nsted Acid Catalyzed Dearomatization by Intramolecular Hydroalkoxylation/Claisen Rearrangement: Diastereo- and Enantioselective Synthesis of Spirolactams

Described herein is a novel Br?nsted acid catalyzed intramolecular hydroalkoxylation/Claisen rearrangement, allowing the practical and atom-economic synthesis of a range of valuable spirolactams from readily available ynamides in generally good to excellent yields with excellent diastereoselectivities and broad substrate scope. Importantly, an unexpected dearomatization of nonactivated arenes and heteroaromatic compounds is involved in this tandem sequence. Moreover, an asymmetric version of this tandem cyclization was also achieved by efficient kinetic resolution by chiral phosphoric acid catalysis. In addition, the [3,3]-rearrangement is shown to be kinetically preferred over the related [1,3]-rearrangement by theoretical calculations.

Cyclopenta[b]annulation of Heteroarenes by Organocatalytic γ′[C(sp3)?H] Functionalization of Ynones

A new approach for the cyclopenta[b]annulation of heteroarenes through metal-free and directing-group-free γ′[C(sp3)?H] functionalization and intramolecular hydroalkylation of ynones has been developed. In an unprecedented event, nucleophilic addition of an organophosphine to the designed ynones triggers γ′[C(sp3)?H] functionalization, leading to the formation of heteroaryl-based ortho-quinodimethane (oQDM) intermediates that undergo carbocyclization to provide cyclopentannulated heteroarenes in good yields and excellent stereoselectivities. Deuterium-labeling experiments substantiated the proposed reaction mechanism as well as the speculated epimerization.

Organocatalytic asymmetric Michael addition of aliphatic aldehydes to indolylnitroalkenes: Access to contiguous stereogenic tryptamine precursors

Because of the importance of the indole framework and the versatile transformation of nitro and formyl groups, the efficient synthesis of optically pure 2-alkyl-3-(1H-indol-3-yl)-4-nitrobutanals, one type of tryptamine precursors are of great interest for pharmaceutical and biological research. Herein, the Michael addition of aliphatic aldehydes to indolylnitroalkenes has been developed using (S)-diphenylprolinol trimethylsilyl ether as an organocatalyst, which provides the desired optically pure syn 2-alkyl-3-(1H-indol-3-yl)-4-nitrobutanal derivatives in up to 98% yield with up to >99:1 dr and >99% ee. To show the synthetic usefulness of this methodology, optically active 2-alkyl-4-nitro-3-(1-tosyl-1H-indol-3-yl)butan-1- ol and tryptamine derivatives are readily obtained by stepwise systematic transformations.

Catalytic asymmetric diazoacetate cyclopropanation of 1-tosyl-3- vinylindoles. A route to conformationally restricted homotryptamines

(Chemical Equation Presented) Substituted 1-tosyl-3-vinylindoles undergo catalytic asymmetric cyclopropanation with ethyl- and tert-butyldiazoacetate to afford N-protected trans-2-(indol-3-yl)-1-cyclopropanecarboxylic esters in good yield and high enantio

A Novel Rearrangement of N-Sulphonylindole 3-Aldehydes and Ketones

3-Acetyl- and 3-formyl-2-methyl-N-sulphonylindoles are partially interconverted on treatment with primary amines.