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Metal-free hydroarylation of the side chain carbon-carbon double bond of 5-(2-arylethenyl)-3-aryl-1,2,4-oxadiazoles in triflic acid.

ABSTRACT: The metal-free reaction of 5-(2-arylethenyl)-3-aryl-1,2,4-oxadiazoles with arenes in neat triflic acid (TfOH, CF₃SO₃H), both under thermal and microwave conditions, leads to 5-(2,2-diarylethyl)-3-aryl-1,2,4-oxadiazoles. The products are formed through the regioselective hydroarylation of the side chain carbon-carbon double bond of the starting oxadiazoles in yields up to 97%. According to NMR data and DFT calculations, N⁴,C-diprotonated forms of oxadiazoles are the electrophilic intermediates in this reaction.

SUBMITTER: Zalivatskaya AS

PROVIDER: S-EPMC5433146 | biostudies-literature | 2017

REPOSITORIES: biostudies-literature

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Metal-free hydroarylation of the side chain carbon-carbon double bond of 5-(2-arylethenyl)-3-aryl-1,2,4-oxadiazoles in triflic acid.

Zalivatskaya Anna S AS Ryabukhin Dmitry S DS Tarasenko Marina V MV Ivanov Alexander Yu AY Boyarskaya Irina A IA Grinenko Elena V EV Osetrova Ludmila V LV Kofanov Eugeniy R ER Vasilyev Aleksander V AV

Beilstein journal of organic chemistry 20170511

The metal-free reaction of 5-(2-arylethenyl)-3-aryl-1,2,4-oxadiazoles with arenes in neat triflic acid (TfOH, CF3SO3H), both under thermal and microwave conditions, leads to 5-(2,2-diarylethyl)-3-aryl-1,2,4-oxadiazoles. The products are formed through the regioselective hydroarylation of the side chain carbon-carbon double bond of the starting oxadiazoles in yields up to 97%. According to NMR data and DFT calculations, N4,C-diprotonated forms of oxadiazoles are t ...[more]

PMID: 28546846

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