221353-36-2

Upstream product

• 1095280-67-3 toluene-4-sulfonic acid 2-tert-butoxycarbonylaminophenyl ester 
• 536-74-3 phenylacetylene 
• 24424-99-5 di-tert-butyl dicarbonate 
• 13141-38-3 2-phenylethynylaniline 
• 615-43-0 2-iodophenylamine 
• 24608-52-4 tert-butyl chloroformate 
• 161117-84-6 tert-butyl 2-iodophenylcarbamate 

Downstream Products

• 138343-89-2 tert-butyl 2-phenyl-1H-indole-1-carboxylate 
• 170956-92-0 N-methyl-2-(2-phenylethynyl)aniline 
• 213623-90-6 (Z)-4-benzylidene-1-methyl-1,4-dihydro-2H-3,1-benzoxazine-2-one 
• 948-65-2 2-phenyl-indole 

Relevant academic research and scientific papers

Synthesis of 3-Methylthioindoles via Intramolecular Cyclization of 2-Alkynylanilines Mediated by DMSO/DMSO-d6 and SOCl2

The intramolecular cyclization of 2-alkynylanilines mediated by DMSO/SOCl2 was found to afford biologically interesting 3-methylthioindoles, which are rarely obtained by the exiting methods. DMSO could also be replaced with its deuterated count

Synthesis of indoles from aroyloxycarbamates with alkynes: Via decarboxylation/cyclization

An efficient Pd-catalyzed decarboxylation/cyclization of aroyloxycarbamates to realize substituted indoles has been disclosed. Terminal alkynes as the coupling partners lead to site specific 2-substituted indoles through two pathways, while internal alkynes with aroyloxycarbamates can be transformed to 2,3-disubstituted indoles directly. This protocol is further demonstrated by the efficient synthesis of indoles as well as the success of employing inexpensive aryl acids as starting materials to construct C-N bonds by releasing CO2.

PtCl4-catalyzed cyclization of N-acetyl-2-alkynylanilines: A mild and efficient synthesis of N-acetyl-2-substituted indoles

An efficient synthesis of N-acetyl-2-substituted indole derivatives via direct intramolecular hydroamination of N-acetyl-2-alkynylaniline derivatives was developed. The reaction could be applied to a wide range of substrates employing only 1–2 mol% of PtCl4 as the catalyst to furnish the desired indole products in moderate to excellent yields. The current protocol is efficient, reliable and scalable, and could serve as an important tool for convenient and rapid access to this important class of N-heterocyclic skeleton from readily available substrates.

Synthesis of Benzofurans and Indoles from Terminal Alkynes and Iodoaromatics Catalyzed by Recyclable Palladium Nanoparticles Immobilized on Siliceous Mesocellular Foam

Herein, we report on the utilization of a heterogeneous catalyst, consisting of Pd nanoparticles supported on a siliceous mesocellular foam (Pd0-AmP-MCF), for the synthesis of heterocycles. Reaction of o-iodophenols and protected o-iodoanilines with acetylenes in the presence of a Pd nanocatalyst produced 2-substituted benzofurans and indoles, respectively. In general, the catalytic protocol afforded the desired products in good to excellent yields under mild reaction conditions without the addition of ligands. Moreover, the structure of the reported Pd nanocatalyst was further elucidated with extended X-ray absorption fine-structure spectroscopy, and it was proven that the catalyst could be recycled multiple times without significant loss of activity.

Borane-catalyzed indole synthesis through intramolecular hydroamination

The reaction of 2-alkynyl anilines with catalytic amounts of B(C6F5)3 (5 mol%) resulted in the formation of 2-substituted indoles according to an intramolecular hydroamination in good to excellent yields. Reaction intermediates as well as products were characterized by NMR spectroscopy and by X-ray crystallography. The domino hydroamination/hydrogenation sequence allowed the efficient synthesis of tetrahydroquinoline 8 in good yield.

Silver-catalyzed incorporation of carbon dioxide into o-alkynylaniline derivatives

Benzoxazine-2-one derivatives are important heterocycle structures because of their various pharmaceutical activities, though their synthetic methods had been limited. In some cases, toxic reagents, such as phosgene or carbon monoxide, are required. It was found that a silver catalyst successfully promoted the incorporation of CO2 into o-alkynylanilines to afford the corresponding benzoxazine-2-ones bearing Z exo-olefin via 6-exo-dig cyclization at the activated C-C triple bond.

A general palladium-catalyzed sonogashira coupling of aryl and heteroaryl tosylates

Coupled up: A new general palladium-catalyzed procedure for the cross-coupling of aryl and heteroaryl tosylates is described. This highly versatile and efficient process can be used for the synthesis of a wide variety of functionalized alkynes (see scheme).

Convenient synthesis of 2-substituted indoles from 2-ethynylanilines with tetrabutylammonium fluoride

The cyclization reaction of various 2-ethynylanilines, which were easily synthesized from 2-haloanilines by the palladium-catalyzed reaction with terminal alkynes, with tetrabutylammonium fluoride (TBAF) to yield 2-substituted indoles proceeded at refluxing or room temperature in THF in excellent yields without affecting the bromo, chloro, cyano, ethoxycarbonyl, and ethynyl groups.