Zirconium complexes phosphorus ligands

Recently an example of white phosphorus activation by complexes containing diamidodiphosphine macrocycle 63 was found. A new dinuclear zirconium complex 71 that has a bridging intact planar square P4 unit was obtained in the reduction of 65 using white phosphorus as an additional ligand (Scheme 12.27) [82]. 

The bridging zirconium phosphinidene complexes in Fig. 7.30 are expected to resonate upheld from the terminal ones in Fig. 7.29, since terminal phosphinidene complexes are far better suited for. -donor interactions of the phosphorus atom towards the metal than are the bridging ligands. 

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