π‐Diamond: A Diamondoid Superstructure Driven by π‐Interactions

Modulating the arrangement of superstructures through noncovalent interactions has a significant impact on macroscopic shape and the expression of unique properties. Constructing π‐interaction‐driven hierarchical three‐dimensional (3D) superstructures poses challenges on account of limited directional control and weak intermolecular interactions. Here we report the construction of a 3D diamondoid superstructure, named π‐Diamond, employing a ditopic strained Z‐shaped building block comprising a porphyrin unit as bow‐limb double‐strapped with two m‐xylylene units as bowstring. This superstructure, reminiscent of diamond's tetrahedral carbon composition, is composed of double‐walled tetrahedron (DWT) driven solely by π‐interactions. Hetero‐π‐stacking between porphyrin and m‐xylylene panels drive the assembly of four building blocks predominantly into a DWT, which undergoes extension to create an adamantane unit and eventually a diamondoid superstructure wherein each porphyrin panel is shared by two neighboring tetrahedra through hetero‐π‐stacking. π‐Diamond exhibits a solid‐state fluorescent quantum yield 44 times higher than that of tetraphenylporphyrin along with excellent photocatalytic performance. The precise 3D directionality of π‐interactions, achieved through strained multipanel building blocks, revolutionizes the assembly of hierarchical 3D superstructures driven by π‐interactions.