<i>p</i>-TsOH promoted synthesis of benzo-fused O-heterocycles from alkynols<i>via</i>ring contraction and C–O scission strategy
作者:Gopal Chandru Senadi、Jeh-Jeng Wang
DOI:10.1039/c8gc00749g
日期:——
Here, we report the first divergent synthesis of benzo-fused O-heterocycles by p-toluene sulfonic acid promoted cascade reactions involving alkyne hydration, doublecyclization, ring contraction and C–O bond cleavage from alkynols. The reaction mechanism was validated by obtaining the X-ray structure of fused benzo[b]oxepine intermediates. Moreover, some of the obtained derivatives could be transformed
在这里,我们报道了由对甲苯磺酸促进苯并稠合的O杂环的首次发散合成,该反应促进了级联反应,涉及炔烃水合,双环化,环收缩和炔醇裂解C-O键。通过获得熔融的苯并[ b ]氧杂环庚烷中间体的X射线结构来验证反应机理。而且,一些获得的衍生物可以转化为2,3-二取代的萘醌,作为天然产物和生物活性分子中的重要结构基序。
Palladium-catalyzed annulations of arynes with 2-(2-iodophenoxy)-1-substituted ethanones
作者:Rong-Jiang Li、Shao-Feng Pi、Yun Liang、Zhi-Qiang Wang、Ren-Jie Song、Guo-Xiang Chen、Jin-Heng Li
DOI:10.1039/c0cc02720k
日期:——
Palladium-catalyzedannulations of arynes with 2-(2-iodophenoxy)-1-substituted ethanones for the synthesis of 6H-benzo[c]chromenes are presented. This mild route allows formation of two new carbon-carbon bonds via an alpha-arylation/annulation process.