The Divergent Cascade Reactions of Arylalkynols with Homopropargylic Amines or Electron-Deficient Olefins: Access to the Spiro-Isobenzofuran-<i>b</i>-pyrroloquinolines or Bridged-Isobenzofuran Polycycles
作者:Lun Wang、Lingyan Liu、Weixing Chang、Jing Li
DOI:10.1021/acs.joc.8b00691
日期:2018.8.3
Two divergent cascade reactions of arylalkynols with homopropargylic amines or electron-deficient olefins were developed to synthesize the spiro-isobenzofuran-b-pyrroloquinolines or bridged-isobenzofuran heterocycles in good yields, respectively. One reaction actually involved intramolecular 5-endo-dig hydroamination cyclization–protonation of homopropargylic amines to give cycloiminium ions and intramolecular
Acid-Catalyzed [4+1]-Dearomatization Spiroannulation of Hydroquinones and Naphthols
作者:Zhi Li、Nan Ding
DOI:10.1055/a-2123-7565
日期:2023.12
convenient methods to access spirocyclic cyclohexadienone derivatives. The Lewis acid Bi(OTf)3 exhibited the best catalytic performance when a 1,2-dialkynylbenzene was used as the electrophile for the spiroannulation, whereas the Brønsted acid benzene-1,2-disulfonic acid was the best catalyst when 2-ethynylbenzylic esters were used as electrophiles. Most of the reaction conditions are mild, efficient, and