38072-75-2

Upstream product

• 120-72-9 indole 
• 2746-25-0 p-Methoxybenzyl bromide 
• 85678-42-8 2-(bromomethyl)-3-(phenylthio)-1-(phenylsulfonyl)-1H-indole 
• 100-66-3 methoxybenzene 
• 496-15-1 1-indoline 
• 105-13-5 4-Methoxybenzyl alcohol 
• 3419-91-8 N-(2-pyridyl)indole 
• 104-93-8 p-methylanizole 
• 63158-55-4 acetic acid 1H-indol-2-ylmethyl ester 
• 5720-07-0 4-methoxyphenylboronic acid 
• 24621-70-3 2-(hydroxymethyl)indole 
• 3770-50-1 2-carbethoxyindole 
• 144465-22-5 1-phenylsulfonyl-2-(4-methoxybenzyl)-3-(phenylthio)-1H-indole 

Relevant academic research and scientific papers

Synthesis of Indole/Benzofuran-Containing Diarylmethanes through Palladium-Catalyzed Reaction of Indolylmethyl or Benzofuranylmethyl Acetates with Boronic Acids

The palladium-catalyzed synthesis of indole/benzofurancontaining diarylmethanes starting from indolylmethyl or benzofuranylmethyl acetates with boronic acids has been investigated. The success of the reaction is influenced by the choice of precatalyst: with indolylmethyl acetates the reaction works well with [Pd(η3-C3H5)Cl]2/XPhos while with benzofuranylmethyl acetates Pd2(dba)3/XPhos is more efficient. The good to high yields and the simplicity of the experimental procedure make this protocol a versatile synthetic tool for the preparation of 2- and 3-substituted indoles and 2-benzo[b]furans. The methodology can be advantageously extended to the preparation of a key precursor of Zafirlukast.

Nickel-Catalyzed C(sp2)-H/C(sp3)-H Oxidative Coupling of Indoles with Toluene Derivatives

Nickel-catalyzed oxidative C(sp2)-H/C(sp3)-H coupling of indoles with toluene derivatives is successfully achieved in the presence of 2-iodobutane as the oxidant. This method allows the selective C-2 benzylation of indoles with toluene derivatives over the alkylation with 2-iodobutane and permits the coupling of diversified indoles via the monochelation assistance. The reaction proceeded through a single-electron-transfer (SET) process, wherein both the C-H nickelation of indole and the C-H activation of toluene derivatives have a significant effect on the entire reaction rate. The synthetic utility of this nickel-catalyzed protocol is demonstrated by the facile removal of the directing group and by the convenient synthesis of the melatonin receptor antagonist Luzindole derivatives.

Selective catalytic C-H alkylation of alkenes with alcohols

Alkenes and alcohols are among the most abundant and commonly used organic feedstock in industrial processes. We report a selective catalytic alkylation reaction of alkenes with alcohols that forms a carbon-carbon bond between vinyl carbon-hydrogen (C-H) and carbon-hydroxy centers with the concomitant loss of water. The cationic ruthenium complex [(C6H6)(PCy 3)(CO)RuH]+BF4- (Cy, cyclohexyl) catalyzes the alkylation in solution within 2 to 8 hours at temperatures ranging from 75° to 110°C and tolerates a broad range of substrate functionality, including amines and carbonyls. Preliminary mechanistic studies are inconsistent with Friedel-Crafts-type electrophilic activation of the alcohols, suggesting instead a vinyl C-H activation pathway with opposite electronic polarization.

3-(o-Trifluoroacetamidoaryl)-1-propargylic esters: common intermediates for the palladium-catalyzed synthesis of 2-aminomethyl-, 2-vinylic, and 2-alkylindoles

3-(o-Trifluoroacetamidoaryl)-1-propargylic esters have been used as common synthetic intermediates for the preparation of a variety of 3-unsubstituted 2-substituted indoles. Treating ethyl 3-(o-trifluoroacetamidoaryl)-1-propargylic carbonates unsubstituted or containing an aryl substituent at the propargylic carbon with piperazines and Pd(PPh3)4 in THF at 80 °C affords 2-(piperazin-1-ylmethyl)indoles in excellent yields. Good to excellent yields of 2-aminomethylindoles are also obtained with other secondary amines. Ethyl 3-(o-trifluoroacetamidoaryl)-1-propargylic carbonates bearing an alkyl substituent at the propargylic carbon and ethyl 3-(o-trifluoroacetamidoaryl)-1-propargylic acetates disubstituted at the propargylic carbon give 2-vinylic indoles with the Pd(OAc)2/PPh3 combination and Et3N in THF at 80 °C. Formation of 2-vinylic indoles is quite stereoselective, generating trans vinylic derivatives, at least with the substrates that we have investigated. In the presence of formic acid, Et3N, and Pd(PPh3)4 in MeCN at 80 °C, ethyl 3-(o-trifluoroacetamidoaryl)-1-propargylic carbonates afford 2-alkylindoles in good to excellent yields.

Electrophilic alkylations in neutral aqueous or alcoholic solutions

Acid-free Friedel-Crafts chemistry: A paradox? Nucleophilicity scales, based on reactions with benzhydrylium ions, show that many π systems are more nucleophilic than aqueous or alcoholic solutions that are generally employed as solvents for SN1 reactions. Solvolytically generated carbocations can, therefore, be trapped by donor-substituted arenes and alkenes to form products of Friedel-Crafts-type reactions in neutral aqueous solutions (see scheme).

Indol-2-yltributylstannane: A versatile reagent for 2-substituted indoles

A general method for 2-substituted indoles via the palladium-catalyzed coupling of indol-2-ylstannanes is described. (N-Methylindol-2-yl)tributylstannane (1) reacts with a variety of electrophiles under very mild conditions. [N-tert-Butoxycarbonyl)indol-2

A convenient synthesis of 2-arylmethylindoles

Methoxy substituted arenes 2 were alkylated with 1-benzenesulfonyl-2-bromomethyl-3-phenylthioindole (1) using palladium chloride to give the alkylsubstituted arenes 3, which on Raney nickel followed by sodium hydroxide treatment gave 2-arylmethylindoles 4