Supporting multiple organometallic catalysts on poly(norbornene) for cyanide addition to α,β-unsaturated imides
作者:Nandita Madhavan、William Sommer、Marcus Weck
DOI:10.1016/j.molcata.2010.10.023
日期:2011.1
A two-catalyst system comprising of salen(AlCl) and pybox(ErCl3) complexes supported onto poly(norbornene) has been developed. As a proof of concept the activity of the two-catalyst system was gauged for the addition of cyanide to α,β-unsaturated imides which has been shown to follow a bimetallic mechanism. The activity of the supported two-catalyst system was significantly higher than catalytic systems
由Salen(AlCl)和pybox(ErCl 3)组成的双催化剂系统)已开发了支持聚(降冰片烯)的配合物。作为概念的证明,测定了在α,β-不饱和酰亚胺中氰化物的加成,并证明了遵循双金属机理的两催化剂体系的活性。负载型两种催化剂体系的活性明显高于衍生自两种催化剂混合物的催化体系。另外,该共聚物可以容易地回收并重复使用多达3个循环,而没有明显的转化率和产率损失。然而,在随后的每个循环中观察到氰化物加合物的对映选择性降低,这表明催化选择性有所降低。报道的策略为在基于催化剂的一锅级联反应的同一聚合物主链上支持多种催化剂开辟了途径。