Dendrimer Assisted Solid Phase Synthesis of Heterobimetallic Asymmetric Catalyst

催化剂在大分子载体上的固定化通过使它们能够回收和再利用而削弱了环境友好的过程。困难在于将配体适当地定向在载体上以产生活性催化剂。配体在聚合物上的随机引入限制了它们在莫来石催化剂中的应用，并且不能适用于复杂的催化剂，例如多组分组成的不对称催化剂，MAC（例如AlLibis（联萘酚）络合物（ALB））。为了克服这个困难，最初开发了一种dendnmer支持的MAC。树枝状大分子负载的MAC可以催化多种对映异构体的不对称反应。最近，我们还提出了一个新的概念，通过共聚固定MAC。在交联剂的存在下，将稳定且易于替换的催化剂类似物与单体聚合。用催化活性金属取代聚合物中的连接基团或元素得到活性催化剂。因此，可以容易地控制所得聚合物中每个配体的位置和取向。此外，还合成了可溶性线性和树枝状的含手性联萘配体的聚合物。这些可溶性聚合物负载的MAC在不对称合成中表现出很高的催化活性。同时，还研究了球形功能化粒子的高效合成。

Immobilization of catalysts on macromolecular supports fmilitates environmentally benign processes by enabling their recovery and reuse, The difficulty lies in orienting the ligands suitably on the support for the generation of the active catalyst. Random introduction of Iigands on the polymer restricts their application to moraonuclear catalysts and cannot be applicable to intricate catalysts such as the multicomponent consisting asymmetric catslyst, MAC (e.g. AlLibis(binaphthoxide) complex (ALB)). To overcome this difficulty, initially a dendnmersupported MAC was developed. Dendrimersupported MAC was found to catalyze various kinds of asymmetric reaction with high enantioeontnol. Recently we also presented a new concept for immobilizing MACs by copolymerization. A stable and easily replaceable catalyst analog was polymerized with a monomer in the presence of a crosslinker. Replacernent of the connecting group or element in the polymer with the catalytically active metal afforded the active catalyst. Thus the posifion and orientation of each ligand in the resulting polymers can be easily controlled. In addition soluble linear and dendronised polymers containing chiral binaphthol ligand were synthesized. These soluble polymnersupported MACs exhibited high catalyst activity in asymmetric synethesis. Highly effective synthesis of functionalized particles with spherical shape was also examnined.