Diastereoselectivity Control in the Zirconocene-Mediated Ring Contraction of 4-Vinylfuranosides to Enantiopure Multiply Functionalized Cyclobutanes
作者:Leo A. Paquette、Nicolas Cunière
DOI:10.1021/ol020063h
日期:2002.5.1
[reaction: see text] The ringcontraction induced by treatment of 4-vinylfuranosides with zirconocene in the presence of boron trifluoride etherate can be rendered highly diastereoselective by proper adjustment of substituent stereochemistry. The two competing transition states that are seemingly involved appear to be usefully sensitive to nonbonded steric interactions.
Stereo-controlled total syntheses of ieodomycins A and B using d-glucose based chiral pool approach
作者:Videsh T. Salunkhe、Sandeep Bhosale、Prasad Punde、Debnath Bhuniya、Summon Koul
DOI:10.1016/j.tetlet.2013.03.002
日期:2013.5
The first stereo-controlled totalsyntheses of ieodomycins A and B have been accomplished in 15 steps using the chiral pool approach starting from d-glucose. The key features of this synthetic strategy are Wittig olefination, indium catalyzed Barbier reaction, and Martin sulfurane catalyzed dehydration to achieve preferential formation of the desired E isomer.