A Family of Porphyrin Nanotubes Assembled from Five Structural Building Blocks

A porphyrin nanotube (PNT) of composition Cd 2 (TPyP)(sez) 2 (TPyP = 5,10,15,20‐tetra(4‐pyridyl)porphyrin, sez = 1,2,5‐benzoselenadiazole‐5‐carboxylate) has recently been shown to be a robust crystalline adsorbent for a variety of guests. The assorted molecular and metal components of the tube may be substituted with other units which yield structurally similar materials. These new variations of the original nanotubes are obtained by incorporating different metal centres within the porphyrin macrocycles, as well as employing other organic bridging and penetrating ligands. All derivatives crystallise as structurally similar nanotubes. The study has been extended to examine the crystallographic impact of the inclusion of solvent molecules. This work further illustrates the remarkable persistence of this type of porous assembly despite the integration of a variety of molecular building blocks. The investigation provides a strong indication that this family of PNTs is potentially enormous, offering the opportunity to tailor the host properties for specific purposes.