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Electrophilic Vinylation of Thiols under Mild and Transition Metal-Free Conditions.

ABSTRACT: The iodine(III) reagents vinylbenziodoxolones (VBX) were employed to vinylate a series of aliphatic and aromatic thiols, providing E-alkenyl sulfides with complete chemo- and regioselectivity, as well as excellent stereoselectivity. The methodology displays high functional group tolerance and proceeds under mild and transition metal-free conditions without the need for excess substrate or reagents. Mercaptothiazoles could be vinylated under modified conditions, resulting in opposite stereoselectivity compared to previous reactions with vinyliodonium salts. Novel VBX reagents with substituted benziodoxolone cores were prepared, and improved reactivity was discovered with a dimethyl-substituted core.

SUBMITTER: Castoldi L

PROVIDER: S-EPMC7497129 | biostudies-literature | 2020 May

REPOSITORIES: biostudies-literature

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Electrophilic Vinylation of Thiols under Mild and Transition Metal-Free Conditions.

Castoldi Laura L Di Tommaso Ester Maria EM Reitti Marcus M Gräfen Barbara B Olofsson Berit B

Angewandte Chemie (International ed. in English) 20200615 36

The iodine(III) reagents vinylbenziodoxolones (VBX) were employed to vinylate a series of aliphatic and aromatic thiols, providing E-alkenyl sulfides with complete chemo- and regioselectivity, as well as excellent stereoselectivity. The methodology displays high functional group tolerance and proceeds under mild and transition metal-free conditions without the need for excess substrate or reagents. Mercaptothiazoles could be vinylated under modified conditions, resulting in opposite stereoselect ...[more]

PMID: 32395880

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