Atypical Mode of [3 + 2]-Cycloaddition: Pseudo-1,3-dipole Behavior in Reactions of Electron-Deficient Thioamides with Benzynes
作者:Juntian Zhang、Annika C. S. Page、Vignesh Palani、Junhua Chen、Thomas R. Hoye
DOI:10.1021/acs.orglett.8b02133
日期:2018.9.21
Thioamides bearing electron-withdrawing groups on the thiocarbonyl carbon atom react with benzynes [generated by the hexadehydro-Diels–Alder cycloisomerization] in an unprecedented fashion. Namely, the dihydrobenzothiazole products are consistent with a pathway involving initial formation of a stabilized ammonium ylide by a rare type of [3 + 2]-cycloaddition reaction. The fate of this species depends