Recycling in ionic liquids

There are many examples showing the possibilities for designing catalysts specifically for sustained recyclability in ionic liquids. A recent example is the synthesis of an alkene ring-closing metathesis (RCM) catalyst for the RCM of dienes (Scheme 21) 188). 

However, the conversion and enantioselectivity were slowly decreased from the fifth run onwards (entries 21-25). Nevertheless, these results clearly demonstrated the effects of ionic tag on the catalyst recycling in ionic liquids. 

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