'Green' catalysts for green chemistry;new concepts in olefin metathesis catalysts separation and reuse

摘要

Olefin metathesis is a simple and effective synthetic tool which is used to create many compounds which otherwise would require complex multi-step syntheses.However,there is one disadvantage related with the use of modern homogeneous metathesis catalysts-it is often not possible to remove heavy metal-containing by-products from the end product.This is a particular problem in the pharmaceutical industry,where it is a necessity for compounds to be of high purity and contain no toxic impurities.Several attempts have been made to immobilize metathesis catalysts on solid or soluble supports.This paper reports some new concepts for Hoveyda-type ruthenium catalysts separation and reuse,either via immobilization in a liquid phase or various phase-separation techniques.