First-Generation Ruthenium Indenylidene Catalysts Bearing a Bidentate Dichalcogenoimidodiphosphinate Ligand

2 First-Generation Ruthenium Indenylidene Catalysts Bearing a Bidentate Dichalcogenoimidodiphosphinate Ligand 

4 Preparation of Ruthenium Indenylidene Catalysts from RuCI (PPh ) 401 NHC 

The saturated imidazolinylidene carbenes are known to be much more air and moisture sensitive than their unsaturated counterparts [51a], and their direct use is not straightforward. However, operating under well-controlled. 

Another strategy to introduce both saturated and unsaturated NHCs to complex 6 was subsequently reported by Delaude and coworkers [57]. Stable, zwitterionic NHC carbon dioxide adducts were prepared via the deprotonation of imidazol(in)ium chloride with potassium bis(trimethylsilyl)amide, followed by reaction with CO2. In the presence of complex 6 in refluxing THF, these carbene precursors decomposed via the elimination of CO2, and the resulting ruthenium indenylidene complexes, featuring either an unsaturated or a 

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