School of Chemistry, Bharathidasan University, Tiruchirappalli, Tamil Nadu 620 024, India.
J Org Chem. 2023 Mar 17;88(6):3903-3908. doi: 10.1021/acs.joc.2c02768. Epub 2023 Mar 6.
A series of benzo[]pyrrolo[2,1-]thiazoles was synthesized by (3 + 2) annulation of aroyl-substituted donor-acceptor cyclopropanes with benzothiazoles. The annulation, promoted by a substoichiometric amount of Sc(OTf), takes place through the formation of the respective dearomatized (3 + 2) adducts, followed by unexpected decarbethoxylative and dehydrogenative rearomatization to afford fully aromatized products. The unusual reactivity is attributed to the presence of an extra aroyl group in the donor-acceptor cyclopropanes.
通过酰基取代的给体-受体环丙烷与苯并噻唑的（3 + 2）环加成反应，合成了一系列苯并[吡咯并[2,1-]噻唑。在亚化学计量的 Sc（OTf）的促进下，通过形成各自去芳构化的（3 + 2）加合物进行环加成，随后发生出乎意料的脱乙氧基化和脱氢芳构化，得到完全芳构化的产物。这种不寻常的反应性归因于给体-受体环丙烷中存在额外的酰基。
