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
Efficient syntheses of α-pyridones and 3(2H)-isoquinolones through ruthenium-catalyzed cycloisomerization of 3-en-5-ynyl and o-alkynylphenyl nitrones
作者:Kamalkishore Pati、Rai-Shung Liu
DOI:10.1039/b910773h
日期:——
We report a new catalytic synthesis of α-pyridones and 3(2H)-isoquinolones from readily available 3-en-5-ynyl nitrones and o-alkynylphenyl nitrones; the reaction mechanism is proposed to involve iminyl ketene species through an oxygen transfer process.
cycloisomerization and intermolecular [5+2] cycloaddition reaction of 2-ethynylphenyl-substituted nitrones with methyleneindolinones was realized. The process includes the palladium(II)-promoted in situ formation of azomethine ylide and the following chiral N,N'-dioxide-Co(II) complex-catalyzed regio-, diastereo-, and enantioselective [5+2] cycloaddition reaction. The desired spiro-tropanyl oxindoles were obtained
Palladium-Catalyzed Aminomethylative Oppolzer-Type Cyclization of Enynes: Access to Aminomethylated Benzofulvenes
作者:Renbin Huang、Bangkui Yu、Renren Li、Hanmin Huang
DOI:10.1021/acs.orglett.1c03720
日期:2021.12.17
A novel palladium-catalyzed Oppolzer-type cyclization reaction aided by the aminomethyl cyclopalladated complex has been developed, which provides rapid access to functionalized benzofulvenes with excellent stereoselectivity. The corresponding products can undergo Diels–Alder reaction with maleimides, providing a series of complex polycyclic compounds with excellent regio- and stereoselectivities.
Stereoselective Synthesis of Oxabicyclo[2.2.1]heptenes via a Tandem Dirhodium(II)-Catalyzed Triazole Denitrogenation and [3 + 2] Cycloaddition
作者:Hao Yuan、Jianxian Gong、Zhen Yang
DOI:10.1021/acs.orglett.6b02703
日期:2016.11.4
A novel synthetic strategy for the diastereoselective synthesis of structurally diverse oxabicyclo[2.2.1]heptenes has been developed, featuring a tandemreaction combining a Rh-catalyzed triazole denitrogenation and a novel type of [3 + 2] cycloadditionreaction. This tandemreaction was thought to proceed via a five-membered oxonium ylide intermediate, which was formed by the intramolecular nucleophilic