Reaction of Bicyclic Zirconacyclopentenes with Aldehydes and a Potential Pathway to Condensed 5-7-6(Ar) Ring Systems
作者:Nikola Topolovčan、Illia Panov、Martin Kotora
DOI:10.1002/ejoc.201500248
日期:2015.5
Bicyclic zirconacyclopentenes prepared by the reactions of 1,6- and 1,7-enynes with [Cp2ZrBu2] (Negishi reagent) reacted with a plethora of aldehydes (aryl, heteroaryl, alkyl, α,β-unsaturated) by chemo- and stereoselective insertion into the sp3 C–Zr bond to give the corresponding oxazirconacycloheptenes. Subsequent hydrolysis or halogenolysis provided the corresponding alcohols 4 (31–74 % isolated
通过 1,6- 和 1,7-烯炔与 [Cp2ZrBu2](Negishi 试剂)反应制备的双环 zirconacyclopentenes 通过化学和立体选择性插入与过多的醛(芳基、杂芳基、烷基、α,β-不饱和)反应进入 sp3 C-Zr 键,得到相应的氧杂环庚烯。随后的水解或卤解提供了相应的醇 4(31-74% 的分离产率)或卤化物 10(35-50% 的分离产率)。通过插入 2-碘苯甲醛制备的氧杂环庚烯也在 CuCl 和添加剂的存在下进行分子内偶联,并以合理的分离产率(32-46%)获得了具有稠合 5-7-6(芳基)环系统的化合物。 )。同样的环系统也通过 Pd 催化的二卤衍生物 10 偶联制备(38-42% 1H NMR 产率)。而且,