Supramolecular Porphyrin Chemistry on Flatlands

Organic multidimensional networks featuring porous structures are of great interest since their cavities can be used as receptors for the confinement of functional molecules or nanoreactors for chemical transformations^. The investigation and exploitation of these structures in solution presents several limitations due to the fact that the molecular components cannot be directly and individually addressed at the nanoscale level. In this respect, the deposition and the organization organic molecules at interfaces is an obligatory passage towards the exploitation of these systems in real devices. Specifically, the engineering of such architectures on metal surfaces represents a promising first approach as the structure of the molecular-based assemblies can be studied by scanning probe microscopies, such as Scanning Tunneling Microscope (STM) techniques. Herein we report on the synthesis, photophysical properties and self-organisation of a series of porphyrin derivaitives that, under under UHV conditions, undergo bidimensional self-assembly on metal surfaces leading to marocyclic supramolecules through transition-metal and lanthanide coordinative interactions.  The synthesis of several porphyrin modules has been carried out. The synthetic strategy mainly involved the C(Sp²)-C(Sp) bond formation, achieved by exploiting cross-coupling-type reactions. The characterization of these arrays on surfaces has been accomplished by STM measurements.