In summary, a methodology for the synthesis of phosphinimines from wide-ranging phosphine precursors has been developed to facilitate exploration of new avenues in molecular phosphinimide chemistry. Here, we applied this protocol to prepare rigid, multidendate, tris-phosphinimine scaffolds that serve to stabilize unique mono-and multinuclear cobalt complexes, including the stabilization of a rare, high-spin Co III complex. Structural, computational and magnetometry data support the notion that a trigonally disposed tris(phosphinimide) ligand field is simultaneously weak field and strongly electron releasing. We envision that these new ligand frameworks will serve to stabilize unusual oxidation-and spin states of other late, first row transition metal ions, and efforts on this front are ongoing.