The reaction between [(PNP)NiCl] (1, PNP = 2,5-bis((di-iso-propylphosphino)-methyl)-1H-pyrrolide) and TlPF in the presence of a monodentate phosphine ligand led to cationic nickel phosphine and phosphite complexes, [(PNP)Ni(PHPh)][PF] (2), [(PNP)Ni(PMe)][PF] (3), and [(PNP)Ni{P(OMe)}][PF] (4). Compound 2 can be deprotonated resulting in the generation of a terminal phosphido complex, [(PNP)Ni(PPh)] (5). When 3 is subjected to a base, a methyl proton of PMe is abstracted to afford [(PNP)Ni(CHPMe)] (6), containing a methylene bridge between Ni and the external phosphine. Compounds 2-6 were characterized by single crystal X-ray diffraction in addition to multi-nuclear NMR spectroscopy and elemental analysis.
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