Aryls homoleptic, iron

For this triad, only iron (Table 4.17) gives homoleptic complexes containing (tM — C bonds. The remaining elements form heteroleptic compounds. The stability of phosphine complexes of the type M(aryl)2 (PR3)2 decreases considerably according to the series Ni>Co>Fe. Ruthenium and osmium complexes characteristically activate the C —H bond in coordinated ligands and form compounds with (tM—C bonds as a result of oxidative addition. The following reactions serve as examples ... 

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