The Reactivity of Phosphanylphosphinidene Complexes of Transition Metals Toward Terminal Dihaloalkanes.

The reactivities of phosphanylphosphinidene complexes [(DippN)W(Cl)(η-P-PBu)] (), [(TolP)Pt(η-P═PBu)] (), and [(dppe)Pt(η-P═PBu)] () toward dihaloalkanes and methyl iodide were investigated. The reactions of the anionic tungsten complex () with stochiometric Br(CH)Br ( = 3, 4, 6) led to the formation of neutral complexes with a BuPP(CH)Br ligand or neutral dinuclear complexes with unusual tetradentate BuPP(CH)PPBu ligands ( = 4, 6). The methylation of platinum complexes and with MeI yielded neutral or cationic complexes bearing side-on coordinated BuP-P-Me moieties. The reaction of with I(CH)I gave a platinum complex with a BuP-P-I ligand. When the same dihaloalkane was reacted with , the P-P bond in the phosphanylphosphinidene ligand was cleaved to yield BuPI, phosphorus polymers, [(dppe)PtI] and CH. Furthermore, the reaction of with Br(CH)Br yielded dinuclear complex bearing a tetraphosphorus BuPPPPBu ligand in the coordination sphere of the platinum. The molecular structures of the isolated products were established in the solid state and in solution by single-crystal X-ray diffraction and NMR spectroscopy. DFT studies indicated that the polyphosphorus ligands in the obtained complexes possess structures similar to free phosphenium cations BuP═P-R (R = Me, I) or (BuP═P).