Associative Substitution by Pentadienyl Ligand Ring Slip

Associative Substitution by Pentadienyl Ligand Ring Slip 

The ligand substitution reaction of PPlL,Me with the Ir(ni) complex Cp Ir(PPh3)(Me)-(NHPh) also appeared to occur by a change in haptidty of the cyclopentadieny 1-type ligand from to but the rate data were sUg tly different. In this case, the kinetic expression implied that the reaction occurred in discrete steps reversible ring slip, followed by attack of the incoming ligand on the 16-electron intermediate and dissociation of the PPhj. 

Geometry of T) -dienyl ligands resulting from ring slip. 

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