Sulfonate-Functionalized NHC-Based Ruthenium Catalysts for the Isomerization of Allylic Alcohols in Water. Recyclability Studies

摘要

Two new complexes of the type [Ru(CO3)(η6-arene)(NHC)]Cs, in which the NHC ligand incorporates a sulfonate functionality, have been prepared and fully characterized. The two water-soluble complexes have been tested in the catalytic isomerization of allylic alcohols in water. The p-cymene compound (labeled as 1) was shown to be an excellent catalyst when compared to other related Ru catalysts. This catalyst can be recycled by simple liquid−liquid extractions several times without detected loss of activity.