Iridium complexes phosphorus ligands

In general, two different kinds of iridium precursors are used. Isolated cationic [Ir(COD)2]A complexes and the in situ precursors formed from the neutral dimer [Ir(p-Cl)(COD)]2 by addition of the corresponding phosphorus ligand. 

This chapter collects the most relevant cases of iridium complexes applied in hydrogenation reaction classified according to the nature of the phosphorus ligand. 

In other cases, oxidative addition from a phosphorus ligand to iridium centers producing hydrido complexes was observed ... 

According to theoretical calculations [114], the most stable modification of a neutral P8 ligands is expected to be the cuneane structure (C), which is found in the phosphorus allotrope known as Hittorff s phosphorus [115,116]. Surprisingly, a ligand conforming to this structural motif has been stabilized in the mixed iron/iridium complex [ Cp Ir(CO) 2(p,q2 2 1 1 1-P8) Cr(CO)5 3] (90), prepared either by photolysis or thermolysis of [Cp Ir(CO)2] with P4 in the presence of excess [Cr(CO)5(thf)] (Scheme 4) [35]. The same unit has also been recognized in the iron derivatives [[CpMeFe(CO) 2(p,q2 2 l l-P8)[CpMeFe(CO)2 2]... 

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