Studies on monoterpene glucosides and related natural products. XLV. Synthesis of 13C-labeled acyclic monoterpenes for studies on the mechanism of the iridane skeleton formation in the biosynthesis of iridoid glucosides.
Diol desymmetrization as an approach to the synthesis of unsymmetrical dienyl diesters
作者:David J. Phillips、Kathryn S. Pillinger、Wei Li、Angela E. Taylor、Andrew E. Graham
DOI:10.1016/j.tet.2007.07.089
日期:2007.10
The tandem oxidation/Wittig olefination of unactivated diols utilizing manganese dioxide produces α,β-unsaturated hydroxy esters in high yields in a highly effective desymmetrization process. The formation of small quantities of the corresponding lactones suggests that the reaction may proceed through a lactol intermediate in some cases. The α,β-unsaturated hydroxy esters are transformed into symmetrical
Intramolecular Aminyl and Iminyl Radical Additions to α,β-Unsaturated Esters. Diastereoselective Tandem Cyclofunctionalization and Hydrogen Transfer Reactions
作者:Yvan Guindon、Brigitte Guérin、Serge R. Landry
DOI:10.1021/ol0160809
日期:2001.7.1
[reaction: see text] A tandem process featuring intramolecular aminyl radical cyclofunctionalization and hydrogen transfer affords 2,3-trans-disubstituted pyrrolidines with anti or syn diastereoselectivity. The extension of this strategy to iminyl radicals gives trans-anti pyrrolenines with high levels of 1,2-induction in both steps of the tandem process.