Catalytic Asymmetric Intramolecular [4+2] Cycloaddition of In Situ Generated <i>ortho</i>
-Quinone Methides
作者:Youwei Xie、Benjamin List
DOI:10.1002/anie.201612149
日期:2017.4.24
Herein, we describe the first catalytic asymmetricintramolecular [4+2] cycloaddition of in situ generated ortho‐quinone methides. In the presence of a confined chiral imidodiphosphoric acid catalyst, various salicylaldehydes react with dienyl alcohols to give transient ortho‐quinone methide intermediates, which undergo an intramolecular [4+2] cycloaddition to provide highly functionalized furanochromanes
Intramolecular [1 + 4 + 1] Cycloaddition: Establishment of the Method
作者:Douglass F. Taber、Pengfei Guo、Na Guo
DOI:10.1021/ja103551x
日期:2010.8.18
bicyclic and polycyclic ring systems having defined relative and absolute configuration. Approaches that allow the construction of more than one carbocyclic ring at a time have proven valuable, in particular those that allow at the same time the control of an array of new stereogenic centers. One of the most general and most widely used protocols has been the intramolecularDiels-Alder [4 + 2] cycloaddition