Self‐Templating and In Situ Assembly of a Cubic Cluster‐of‐Clusters Architecture Based on a {Mo 24 Fe 12 } Inorganic Macrocycle

Engineering self‐templating inorganic architectures is critical for the development of bottom‐up approaches to nanoscience, but systems with a hierarchy of templates are elusive. Herein we describe that the cluster‐anion‐templated (CAT) assembly of a {CAT}⊂{Mo 24 Fe 12 } macrocycle forms a giant ca. 220 nm 3 unit cell containing 16 macrocycles clustered into eight face‐shared tetrahedral cluster‐of‐clusters assemblies. We show that {CAT}⊂{Mo 24 Fe 12 } with different CATs gives the compounds 1 – 4 for CAT=Anderson {FeMo 6 } ( 1 ), Keggin {PMo 12 } ( 2 ), Dawson {P 2 W 18 } ( 3 ), and {Mo 12 O 36 (HPO 3 ) 2 } ( 4 ) polyoxometalates. “Template‐free” assembly can be achieved, whereby the macrocycle components can also form a template in situ allowing template to macrocycle to superstructure formation and the ability to exchange the templates. Furthermore, the transformation of template clusters within the inorganic macrocycle {Mo 24 Fe 12 } allows the self‐generation of an uncapped {Mo 12 O 36 (HPO 3 ) 2 } in compound 4 .