Characterization of Two Zincophosphates (UH‐6 and UH‐10) Synthesized using the Cobalt(III) Sarcophagine Complex as Structure‐directing Agent

The novel zincophosphates UH‐6 (sum formula |[Co(diAMHsar)]| [Zn₂(HPO₄)₃(PO₄)] · H₂O) and UH‐10 (sum formula |([Co(diAMHsar)])₂| [{Zn₂(HPO₄)₃(PO₄)}₂] · H₂O) were synthesized in hydrothermal syntheses employing the chiral sarcophagine complex [Co(diAMHsar)]⁵⁺ as the structure‐directing agent. The inorganic part of UH‐6 consists of pearl‐like chains of alternating [ZnO₄] and [PO₄] tetrahedra, which are connected to the incorporated cobalt complex via numerous hydrogen bonds. UH‐10 was synthesized under similar conditions, but at higher reaction temperatures. In consequence, the crystal structures of UH‐6 and UH‐10 are closely related, although systematic disorder in UH‐10 and the lower symmetry result in a unit cell twice as large as the corresponding unit cell of UH‐6. Interestingly, in both zincophosphates only one enantiomer of the cobalt complex is present, despite the fact that a racemic mixture of the complex salt is used for synthesis. Thermogravimetric analysis and powder X‐ray diffraction of a thermally treated sample of UH‐6 reveals a phase transformation at ca. 300 °C.