Treatment of anhydrous FeX2 (X = Cl, Br) with 2 equivs of the sterically little demanding N,N'-bisphosphino-2,6-diaminopyridine based PNP ligands PNP-Ph, PNP-BIPOL, PNP-Me, PNP-Et, PNP-nPr and PNP-nBu in THF afforded diamagnetic cationic octahedral complexes of the general formula [Fe(3-P,N,P-PNP)(2-P,N-PNP)X]+ featuring a 2-P,N bound PNP ligand. With the sterically more encumbered N-methylated ligand PNPMe-Ph the related complex [Fe(3-P,N,P-PNPMe-Ph)(2-P,N-PNHMe)Cl]+ rather than [Fe(3-P,N,P-PNPMe-Ph)Cl2] was formed. This reaction was accompanied by P-N bond cleavage thereby forming the 2-P,N-bound N-diphenylphosphino-N,N’-methyl-2,6-diaminopyridine ligand. In contrast, with the N-phenylated ligand PNPPh-Et and PNPPh-nPr, despite of small Et and nPr substituents at the phosphorus sites, complexes [Fe(3-P,N,P-PNPPh-Et)Cl2] and [Fe(3-P,N,P-PNPPh-nPr)Cl2] were formed revealing that sterics can be also controlled by substituent variations at the amino N-sites. Depending on the solvent, complexes featuring 2-P,N-bound ligands undergo facile rearrangement reactions to give dicationic complexes of the type [Fe(3-P,N,P-PNP)2]2+ where both PNP ligands are bound in 3-P,N,P-fashion. In the presence of either Ag+ or Na+ salts as halide scavengers this reaction takes place within a few minutes. The pendant PR2 arm of the 3-2-complexes is readily oxidized to the corresponding phosphine sulfides upon treatment with elemental sulfur. This was exemplarily shown for [Fe(3-P,N,P-PNP-nPr)(2-P,N-PNS-nPr)Cl]+. Halide abstraction afforded the dicationic bis-chelated octahedral Fe(II) complex [Fe(3-P,N,P-PNP)2]2+ together with the free SNP ligand rather than [Fe(3-P,N,P-PNP-nPr)(3-S,P,N-PNS-nPr)]2+.