Hafnium complexes phosphorus ligands

The hafnium complexes 9 and 16, respectively, with their preformed 1,3,5-triphosphinine ligands, are suitable substrates for the preparation of the nickel complex 24 [29]. In addition to the complexes with 7] -coordination, a platinum complex with fj -coordination is known. Complex 25, characterized spectroscopically in solution, undergoes hydrolysis with oxidation of the phosphorus atoms of the triphosphinine to afford the f] -platinum complex 26 possessing a hexahydrotriphosphinine ligand in the boat form as demonstrated by an X-ray crystallographic analysis [30]. 

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