A straightforward double intramolecular cyclization of dibenzyl dichalcogenols into a triple bond
作者:Haruki Sashida、Mamoru Kaname、Akemi Nakayama、Hirokazu Suzuki、Mao Minoura
DOI:10.1016/j.tet.2010.04.101
日期:2010.7
contrast, the regioselective tandem 5-exo-dig mode intramolecular ring closure reactions of dibenzyl thiol and selenol having a mono-yne into a triple bond gave the trans-biisobenzothiophene and selenophene as the sole product. However, the similar cyclization of dibenzyl tellurol proceeded in both tandem 5-exo and 6-endo-dig modes to afford the trans-biisobenzotellurophene and ditellurachrysene in good yields
进行了四种含有一个或两个乙炔基的二苄硫属元素醇的分子内环化反应。无论是双5-外型或6-内-挖模式闭环反应区域选择性和立体选择性地进行,得到相应的对称的双(苯并[ c ^从具有二炔基二苄chalcogenols] chalcogenophene)或双(苯并吡喃)衍生物。相比之下,具有单炔基的三苄基二苄基硫醇和硒醇的区域选择性串联5- exo - dig模式分子内闭环反应使反式为-二异苯并噻吩和硒吩是唯一的产品。但是,二苄基碲酚的类似环化反应在串联的5- exo和6- endo - dig模式下进行,从而以1:1的高收率获得了反式-biisobenzotellurophene和ditellurachrysene。还介绍了这些新型化合物的X射线结构分析。