NI(ii) phosphine and phosphide complexes supported by a PNP-pyrrole pincer ligand.

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.

Ag(I) and Tl(I) precursors as transfer agents of a pyrrole-based pincer ligand to late transition metals.

A PNP ligand, PN(pyr)P ((PN(pyr)P)H = 2,5-bis((di-iso-propylphosphino)methyl)pyrrole), which employs a pyrrole unit as a central anionic nitrogen donor, was designed. The corresponding group 10 metal chlorides as well as iridium and ruthenium compounds were isolated. In order to conduct this work, [(PN(pyr)P)Tl] and [(PN(pyr)P)Ag]2 were synthesized and characterized.