Synthesis and Reactivity of Thermally Stable Zirconocene (II) Species Precursors

热稳定二茂锆 (II) 前体的合成和反应活性

基本信息

批准号：
18550089
负责人：
TAKAHASHI Tamotsu
金额：
$ 2.8万
依托单位：
Hokkaido University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2006
资助国家：
日本
起止时间：
2006 至 2007
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-18550089/
关键词：
zirconium divalent complex metallocene zirconacycle indenyl ligand cyclopentadienyl ligand 安定

项目摘要

Reactions of tris (indenyl) zirconium hydride with a variety of alkynes were investigated and evaluated the reactivity of the zirconium complex as zirconocen (II) equivalent. The reaction of tris (indenyl) zirconium hydride with internal alkynes afforded the corresponding zirconacyclopentadienes in high yields. Interestingly, the reaction with terminal arylalkynes produced the2,5-diarylzirconacycles with high selectivity.A reaction of thus obtained bis (indenyl) zirconacyclopentadienes with titanium tetrachloride afforded the corresponding fluorene derivatives via coupling of the diene moiety with the indenyl ligand. This reaction was applicable for alkyl-or aryl-substituted, and bicyclic zirconacyclopentadienes and furnished the substituted fluorenes. Instead of the indenyl ligand, zirconacyclopentadienes having substituted cyclopentadienyl ligands were also applied for the reaction and afforded the corresponding indene derivatives. A comparison of the structural parameters of the zirconacyclopentadienes with the related ones suggested that the coupling reactivity was strongly affected by the distance between the indenyl or cyclopentadienyl ligands and the diene moiety of the zirconacyclopentadienes. The most reactive titanacyclopentadienes have the shortest distance. In addition, the reactivity was increased with increasing the steric bulkiness of the ligand. Titanium tetrachloride played an important role as an oxidant in the reaction.

研究了三（茚基）氢化锆与各种炔烃的反应，并以二茂锆（II）当量评估了锆配合物的反应活性。三(茚基)氢化锆与内炔的反应以高产率提供相应的环戊二烯锆。有趣的是，与末端芳基炔的反应以高选择性生成2,5-二芳基锆环。由此获得的双(茚基)锆环戊二烯与四氯化钛反应通过二烯部分与茚基配体的偶联得到相应的芴衍生物。该反应适用于烷基或芳基取代的双环锆环戊二烯并提供取代的芴。代替茚基配体，具有取代的环戊二烯基配体的锆环戊二烯也用于反应并提供相应的茚衍生物。环戊二烯锆与相关结构参数的比较表明，茚基或环戊二烯基配体与环戊二烯锆的二烯部分之间的距离强烈影响偶联反应性。反应性最强的环戊二烯钛具有最短的距离。此外，反应活性随着配体空间体积的增加而增加。四氯化钛作为氧化剂在该反应中发挥了重要作用。