Iridium catalysts based on heterobidentate ligands

N hard , mainly s-donor I I Vacant coordination site 

Kinetic studies conducted with Ir complexes bearing different counterions provided a plausible explanation of this unusual anion effect [17]. Catalysts with PF as counterion showed first-order rate dependence on the olefin concentration, whereas for catalysts containing BArp as counterion the rate dependence was close to zero order, implying a much faster reaction of the olefin with the catalyst in this case. 

An additional advantage of BArp-based Ir complexes is their stability against moisture and oxygen and hence they can be handled in air, whereas reactions with PF -based complexes require set-up under inert gas atmosphere. Furthermore, it is 

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