High activity metal carbene metathesis catalysts generated using a thermally activated N-heterocyclic carbene precursor
申请人:——
公开号:US20030083445A1
公开(公告)日:2003-05-01
The invention provides a method for converting a less active or slower to initiate system to a higher activity system so that at the end of a polymerization the most active species is present in the system. The invention generally relates to a process for converting a less active or slower to initiate catalyst system to a higher activity catalyst system wherein the process comprises contacting a protected N-heterocyclic carbene with a metathesis catalyst and an olefin in the presence of energy. One of the benefits of the invention is that the amount of catalyst required is less than or lowered in the presence of the protected N-heterocyclic carbene as compared to the amount of catalyst required in the absence of the protected N-heterocyclic carbene. The protected N-heterocyclic carbene can be unsaturated or saturated. In addition, the invention describes novel ruthenium initiators and methods of making the same.
本发明提供了一种将较不活跃或缓慢启动的系统转化为更高活性系统的方法,以便在聚合结束时,系统中存在最活性的物种。本发明通常涉及一种将较不活跃或缓慢启动的催化剂系统转化为更高活性催化剂系统的过程,其中该过程包括在能量存在下,将受保护的N-杂环卡宾与一种交换反应催化剂和一种烯烃接触。本发明的一个好处是,在受保护的N-杂环卡宾存在的情况下,所需催化剂的量比在受保护的N-杂环卡宾不存在的情况下少或降低。受保护的N-杂环卡宾可以是不饱和或饱和的。此外,本发明还描述了新的钌引发剂及其制备方法。