A palladium(II) complex of a new iminophosphine ligand derived from diethylenetriamine and 2-(diphenylphosphino)benzaldehyde

The mononuclear complexes [Pd(oPdien)]X2 {oPdien=N-(2-diphenylphosphinobenzylidene)diethylenetriamine: (4a) X2=[ZnCl4]2−; (4b) X=[PF6]−; (4c) X=Cl−} are described. Complex 4a formed in high yield when [Pd(oPCHO)2Cl2] [oPCHO=2-(diphenylphosphino)benzaldehyde] (1) and [Zn(dien)Cl2] (2) were reacted together in an unsuccessful attempt to template formation of a bimetallic iminophosphine-bridged complex. The X-ray crystal structure of 4b has been determined. The ligand oPdien is the first iminophosphine derived from dien and has been isolated and used to prepare 4c.