Three‐Level Synthetic Strategy Towards Mixed‐Valence and Heterometallic [2×2] Gridlike Arrays

Regioselective, redox, and chiroselective features were used in a three‐tiered synthesis to construct Co ${{{{\rm {\rm III}}\hfill \atop 2\hfill}}}$ M ${{{{\rm {\rm II}}\hfill \atop 2\hfill}}}$ [2×2] grid‐type arrays (M II =Co II , Zn II , Fe II ; see picture). The assemblies are based on a bis(hydrazone) ligand containing ionizable and non‐ionizable compartments. This route allows the cobalt oxidation state to be selectively modified according to the charge on the hydrazone moiety.