Institute of Chemical Research of Catalonia (ICIQ), Av. Països Catalans 16, 43007, Tarragona, Spain.
Dalton Trans. 2011 Apr 7;40(13):3352-64. doi: 10.1039/c0dt01411g. Epub 2011 Feb 4.
The use of olefin metathesis as a construction tool for multimetallic salen-based structures is described. The approach involves mono- and diallyl-functionalized metallosalen complexes that can be directly coupled by metathesis leading to dimetallic species or mixtures of linear and cyclic oligomers. The metathesis of bis-allyl Ni(salen) complexes has been studied in detail. At high concentration it is possible to selectively obtain di-Ni species rather than heavier oligomers while under dilute conditions cyclic rather than linear oligomers are preferentially obtained. A mono-allyl Zn(salphen) complex was efficiently coupled using metathesis to give the di-Zn(salphen) product, which was subsequently transmetalated with a variety of metals to yield dimetallic salens of potential catalytic interest. Finally, a tetranuclear Zn(4) macrocycle was also prepared using buildings blocks obtained by metathesis from commercially available precursors. The methods described herein allow for the facile construction of multi-centered Schiff base complexes of catalytic or supramolecular interest.
本文描述了利用烯烃复分解反应作为构建多金属席夫碱基结构的工具。该方法涉及单烯丙基和二烯丙基官能化的金属茂配合物，它们可以通过复分解直接偶联，得到二金属物种或线性和环状低聚物的混合物。详细研究了双-烯丙基 Ni(salen)配合物的复分解反应。在高浓度下，有可能选择性地获得双 Ni 物种，而不是更重的低聚物，而在稀条件下，优先获得环状低聚物而不是线性低聚物。使用复分解法有效地偶联了一个单烯丙基 Zn(salphen)配合物，得到了双 Zn(salphen)产物，随后用各种金属将其转金属化，得到了具有潜在催化兴趣的二金属席夫碱。最后，还使用商业上可获得的前体通过复分解获得的构建块制备了四核 Zn(4)大环。本文所述的方法允许轻松构建具有催化或超分子兴趣的多中心希夫碱配合物。
