A Facile Synthesis of Enantiopure Tricyclic Furanyl and Pyranyl Derivatives via Tungsten-Mediated Cycloalkenation and Diels−Alder Reaction
摘要:
We report the synthesis of chiral furanyl and pyranyl dienes 1 and 2 based on cycloalkenation of chiral tungsten alkynol complexes. These two dienes bear a chiral 1,3-dioxolane group to control diastereoselective Diels-Alder reactions with electron-deficient olefins. The chiral 1,3-dioxolane substituents of the cycloadducts were degraded into hydrogen atoms to make these molecules possess common furan and pyran rings. Dienes 1 and 2 are good building blocks for enantiopure forms of tricyclic oxygen compounds.
A Facile Synthesis of Enantiopure Tricyclic Furanyl and Pyranyl Derivatives via Tungsten-Mediated Cycloalkenation and Diels−Alder Reaction
作者:Heh-Lung Huang、Rai-Shung Liu
DOI:10.1021/jo0205208
日期:2003.2.1
We report the synthesis of chiral furanyl and pyranyl dienes 1 and 2 based on cycloalkenation of chiral tungsten alkynol complexes. These two dienes bear a chiral 1,3-dioxolane group to control diastereoselective Diels-Alder reactions with electron-deficient olefins. The chiral 1,3-dioxolane substituents of the cycloadducts were degraded into hydrogen atoms to make these molecules possess common furan and pyran rings. Dienes 1 and 2 are good building blocks for enantiopure forms of tricyclic oxygen compounds.
Synthesis of C1–C15 of palmerolide A: tactical advances that can lead to better design strategies for polyketide synthesis
作者:Paratchata Batsomboon、Gregory B. Dudley
DOI:10.1016/j.tetlet.2016.07.014
日期:2016.8
streamlined synthesis of a C1–C15 fragment of palmerolide A is described. Key tactical advances (vis-à-vis previous reports from the Dudley laboratory) include diastereoselective reduction (>20:1 dr) of a C7 ketone using DIP chloride and a modified protecting group strategy that enables both improved step count and end-game efficiency. Asymmetric reduction of linear alkyl vinyl ketonederivatives is a largely