Effective 1,5-, 1,6- and 1,7-remote stereocontrol in reactions of alkoxy- and hydroxy-substituted allylstannanes with aldehydes
作者:John S. Carey、Somhairle MacCormick、Steven J. Stanway、Aphiwat Teerawutgulrag、Eric J. Thomas
DOI:10.1039/c0ob01084g
日期:——
Alk-2-enylstannanes with 4-, 5- and 6-alkoxy- or -hydroxy-substituents are transmetallated stereoselectively with tin(IV) halides to generate allyltin trihalides which react with aldehydes to give (Z)-alk-3-enols with useful levels of 1,5-, 1,6- and 1,7-stereocontrol. Alk-2-enylstannanes with a stereogenic centre bearing a hydroxy or alkoxy group at the 4-, 5- or 6-position, react with overall (Z)-1,5-, 1,6- and 1,7-syn-stereoselectivity with respect to the hydroxy and alkoxy substituents. The analogous reactions of alkoxy- and -hydroxyalk-2-enylstannanes with a methyl bearing stereogenic centre at the 4- or 5-position react with overall (Z)-1,5- and 1,6-anti-stereoselectivity with respect to the hydroxy and methyl substituents.
带有4、5和6-氧烷基或羟基取代基的烯基锡烷通过选择性转金属化与四氯化锡反应生成烯丙锡三卤化物,这些烯丙锡三卤化物与醛反应生成具有良好水平的1,5、1,6和1,7立体控制的(Z)-烯-3-醇。带有氢氧基或氧烷基取代基的烯-2-烯基锡烷在4、5或6位的立体中心与氢氧基和氧烷基取代基相对于整体以(Z)-1,5、1,6和1,7-顺式立体选择性反应。带有在4或5位置有立体中心的氧烷基和羟基烯-2-烯基锡烷的类似反应相对于羟基和甲基取代基以整体(Z)-1,5和1,6-反式立体选择性反应。