We have designed a convergent path for the synthesis of the key fragments (C1–C7 and C6–C22) of phostriecin. The approach not only provides ready access to several biologically active molecules, such as 5‐hydroxygoniothalamin, 5‐acetoxygoniothalamin, and their analogues, but also (S)‐5‐[(S)‐1‐hydroxyallyl]furan‐2(5H)‐one derivatives with cross metathesis as the key reaction.
Stereoselective synthesis of polyenes via heck coupling of vinylboronate esters
作者:Sarah K Stewart、Andrew Whiting
DOI:10.1016/0040-4039(95)00643-q
日期:1995.5
E- and Z-1-alkenyl iodides react with vinylboronate pinacol ester 1 under palladium(0) catalysed, Heck conditions to provide polyenylboronates in moderate yields after purification. The addition of either silver(I) or thallium(I) salts to the reaction mixture is essential. Alkenyl bromides are unreactive under identical reaction conditions.
Stereoselective synthesis of vinyl iodides from vinylboronate pinacol esters using ICI
作者:Sarah K Stewart、Andrew Whiting
DOI:10.1016/0040-4039(95)00644-r
日期:1995.5
Polyenyl-1-boronic acids, with hindered pinacol esters, are difficult to transform into the corresponding Z or E-iodides under literature reaction conditions. However, reaction of trans-polyenyl-1-boronate pinacol esters with sodium methoxide, followed by monochloroiodide provides the corresponding E-iodides, while reaction with monochloroiodide, followed by sodium methoxide provides the corresponding Z-iodides.