Liquid-Phase Synthesis of Chiral Tartrate Ligand Library for Enantioselective Sharpless Epoxidation of Allylic Alcohols
作者:Hong-Chao Guo、Xue-Yan Shi、Xian Wang、Shang-Zhong Liu、Min Wang
DOI:10.1021/jo035818s
日期:2004.3.1
tartrate ligands by liquid-phase synthesis for Sharplessepoxidation of a variety of allylic alcohols through ligand diversity. The influence of substituent in chiral tartrate ligands on the enantioselectivities of the reaction was disclosed. Moderate chemical yields and good enantiomeric excesses were obtained by using soluble polymer-supported tartrate ester in the epoxidation of allylic alcohols with
Biomimetic Synthesis of <i>trans,syn,trans</i>-Fused Polyoxepanes: Remarkable Substituent Effects on the <i>e</i><i>ndo</i>-Regioselective Oxacyclization of Polyepoxides
作者:Jason C. Valentine、Frank E. McDonald、Wade A. Neiwert、Kenneth I. Hardcastle
DOI:10.1021/ja050013i
日期:2005.4.1
and C15 in 1) when the tandem cyclization cascade is terminated by a carbonyl oxygen nucleophile. In contrast to expectations from earlier reports with simpler epoxide substrates, alkyl substituents are not required at internal epoxide positions corresponding to C7 and C11 in polyepoxide 1. Furthermore, we report that trimethylsilyl serves as a removable regioselectivity-directing substituent at positions