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Reactions of Hexadehydro-Diels-Alder (HDDA)-Derived Benzynes with Thioamides: Synthesis of Dihydrobenzothiazino-Heterocyclics.

ABSTRACT: Reaction of thioamides (e.g., II) with benzynes generated by the hexadehydro-Diels-Alder (HDDA) cycloisomerization (e.g., I) produces dihydrobenzothiazines (e.g., III). It is postulated that the reaction proceeds via benzothietene (cf. IV) and o-thiolatoaryliminium (cf. V) intermediates and that the latter undergoes intramolecular 1,3-hydrogen atom migration to produce the penultimate isomeric iminium zwitterions VI.

SUBMITTER: Palani V

PROVIDER: S-EPMC5629071 | biostudies-literature | 2016 Dec

REPOSITORIES: biostudies-literature

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Reactions of Hexadehydro-Diels-Alder (HDDA)-Derived Benzynes with Thioamides: Synthesis of Dihydrobenzothiazino-Heterocyclics.

Palani Vignesh V Chen Junhua J Hoye Thomas R TR

Organic letters 20161201 24

Reaction of thioamides (e.g., II) with benzynes generated by the hexadehydro-Diels-Alder (HDDA) cycloisomerization (e.g., I) produces dihydrobenzothiazines (e.g., III). It is postulated that the reaction proceeds via benzothietene (cf. IV) and o-thiolatoaryliminium (cf. V) intermediates and that the latter undergoes intramolecular 1,3-hydrogen atom migration to produce the penultimate isomeric iminium zwitterions VI. ...[more]

PMID: 27978648

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