Structure of a Fe(4)O(6)-Heteraadamantane-Type Hexacation Stabilized by Chelating Organophosphine Oxide Ligands

Metal-containing heteraadamantanes are compounds of interest due to their spectroscopic and magnetic properties, which make them promising materials for non-linear optics and semiconductors. Herein we report the comprehensive structural characterization of a new coordination compound of the formula [(µ-OH′)(2)(µ-OH″)(4)(O = P(Ph(2))CH(2)CH(2)(Ph(2))P = O)(4){Fe(t-BuOH)}(4)](PF(6))(4)(Cl)(2) with the chelating ligand Ph(2)P(O)-CH(2)CH(2)-P(O)Ph(2). The compound crystallizes as a polynuclear metal complex with the adamantane-like core [Fe(4)O(6)] in the space group I-43d of a cubic system. The single-crystal XRD analysis showed that the crystal contains one symmetrically independent octahedrally coordinated Fe atom in the oxidation state +3. The adamantine-like scaffold of the Fe complex is formed by hydroxy bridging oxygen atoms only. Hirshfeld surface analysis of the bridging oxygen atoms revealed two types of µ-OH groups, which differ in the degree of exposure and participation in long-range interactions. Additionally, the Hirshfeld surface analysis supported by the enrichment ratio calculations demonstrated the high propensity of the title complex to form C-H(…)Cl, C-H(…)F and C-H(…)O interactions.