Reactions of Hexadehydro-Diels–Alder (HDDA)-Derived Benzynes with Thioamides: Synthesis of Dihydrobenzothiazino-Heterocyclics
作者:Vignesh Palani、Junhua Chen、Thomas R. Hoye
DOI:10.1021/acs.orglett.6b03199
日期:2016.12.16
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
硫代酰胺(如II)与六氢-狄尔斯-阿尔德(HDDA)环异构化反应(如I)生成的苯炔反应生成二氢苯并噻嗪(如III)。据推测,该反应通过苯并硫杂环丁烯(参见IV)和邻硫代巯基芳基亚胺(参见V)中间体进行,并且后者经历分子内的1,3-氢原子迁移以产生倒数第二个异构的亚胺基两性离子VI。