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Thiazol-4-one derivatives from the reaction of monosubstituted thioureas with maleimides: structures and factors determining the selectivity and tautomeric equilibrium in solution.

ABSTRACT: 2-(Alkyl(aryl)amino)thiazol-4(5H)-ones can regioselectively be prepared from monoalkyl(aryl)thioureas and maleimides. In solution, the former heterocycles exist in a tautomeric equilibrium with 2-(alkyl(aryl)imino)thiazolidin-4-ones and the substituent on the exocyclic nitrogen atom governs the ratio of these tautomers. Isomers with the alkyl group in the endocyclic position can be obtained from N-methyl(ethyl)thioureas. 2D NMR spectroscopy and DFT calculations rationalize experimental results.

SUBMITTER: Pankova AS

PROVIDER: S-EPMC5238611 | biostudies-literature | 2016

REPOSITORIES: biostudies-literature

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Thiazol-4-one derivatives from the reaction of monosubstituted thioureas with maleimides: structures and factors determining the selectivity and tautomeric equilibrium in solution.

Pankova Alena S AS Golubev Pavel R PR Khlebnikov Alexander F AF Ivanov Alexander Yu AY Kuznetsov Mikhail A MA

Beilstein journal of organic chemistry 20161129

2-(Alkyl(aryl)amino)thiazol-4(5<i>H</i>)-ones can regioselectively be prepared from monoalkyl(aryl)thioureas and maleimides. In solution, the former heterocycles exist in a tautomeric equilibrium with 2-(alkyl(aryl)imino)thiazolidin-4-ones and the substituent on the exocyclic nitrogen atom governs the ratio of these tautomers. Isomers with the alkyl group in the endocyclic position can be obtained from <i>N</i>-methyl(ethyl)thioureas. 2D NMR spectroscopy and DFT calculations rationalize experime ...[more]

PMID: 28144325

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