The tetraanilino phosphonium cation, [P{N(H)Ph}₄]⁺, 1⁺, is sequentially deprotonated by BuⁿLi in thf. The deprotonation reaction of the chloride derivative, 1Cl, was monitored by ³¹P NMR, which revealed the successive formation of the neutral [P{N(H)Ph}₃(NPh)], 2, the monoanionic [P{N(H)Ph}₂(NPh)₂]⁻, 3⁻, the dianionic [P{N(H)Ph}(NPh)₃]²⁻, 4²⁻, and finally the trianionic species [P(NPh)₄]³⁻, 5³⁻. Considering the isoelectronic relationship of oxo, O, and imino groups, NR, as well as hydroxy, –OH, and amino groups, –N(H)R, the neutral complex 2 corresponds to phosphoric acid, H₃PO₄, whereas the anions 3⁻, 4²⁻ and 5³⁻ are analogues of dihydrogen phosphate, H₂PO₄⁻, monohydrogenphosphate, HPO₄²⁻, and orthophosphate ions, PO₄³⁻, respectively. Solid state structures were obtained of 1Cl, 2LiCl(thf)₂, 3Li(thf)_3.5, 3Li₂Cl(thf)_4.25, 3Li₂Cl(thf)₆ and 5Li₄Cl(thf)₄. All systems provide two separate N–P–N chelation sites at opposite ligand faces, either consisting of the di(amino) arrangement P(NH)₂, acting as a double H-bond donor, the di(imino) arrangement PN₂, donating two electron pairs, or the mixed amino imino arrangement P(N)(NH), which supplies both electron pair and H-donor site. Interesting in this aspect is the mixed amino imino derivative 3⁻ which has the ability to chelate a Lewis acid, such as a metal ion, at one face and a Lewis base, such as an anionic or neutral donor at the opposite ligand face. The formation of 1-D aggregates and the entrapment of lithium chloride are key characteristics of the supramolecular structures of the discussed complexes.