Aryne [3 + 2] cycloaddition with N-sulfonylpyridinium imides and in situ generated N-sulfonylisoquinolinium imides: a potential route to pyrido[1,2-b]indazoles and indazolo[3,2-a]isoquinolines
作者:Jingjing Zhao、Pan Li、Chunrui Wu、Hongli Chen、Wenying Ai、Renhong Sun、Hailong Ren、Richard C. Larock、Feng Shi
DOI:10.1039/c2ob06611d
日期:——
The aryne [3 + 2] cycloaddition process with pyridinium imides breaks the aromaticity of the pyridine ring. By equipping the imide nitrogen with a sulfonyl group, the intermediate readily eliminates a sulfinate anion to restore the aromaticity, leading to the formation of pyrido[1,2-b]indazoles. The scope and limitation of this reaction are discussed. As an extension of this chemistry, N-tosylisoquinolinium
与吡啶鎓酰亚胺的芳烃[3 + 2]环加成过程破坏了吡啶环的芳香性。通过在酰亚胺氮上加成磺酰基,该中间体容易消除亚磺酸根阴离子以恢复芳香性,从而导致吡啶并[1,2- b ]吲唑的形成。讨论了该反应的范围和局限性。作为该化学反应的扩展,通过AgOTf催化的6-endo-dig亲电环化反应从N '-(2-炔基亚苄基)-甲苯磺酰肼原位生成的N-甲苯磺酰异喹啉鎓亚胺易于进行芳烃[3 + 2]环加成反应而制得吲哚唑[3,2- a同一锅中的]-异喹啉,为这些潜在的抗癌药提供了高效途径。