Porphyrins, phthalocyanines, and perylenes are compounds with great potential for serving as components of molecular materials that possess unique electronic, magnetic and photophysical properties. In general, a highly specific communication between a large number of these chromophores is required in order to express their function to a maximal level, and for this reason it is of importance to construct arrays in which the molecules are organized in well-defined geometries with respect to their neighbors. This review is an account of some recent efforts to construct highly ordered assemblies of porphyrins, phthalocyanines, and perylenes by means of self-assembly in solution and on surfaces, and by attaching them to polymeric scaffolds.

Molecular Materials by Self‐Assembly of Porphyrins, Phthalocyanines, and Perylenes

Since the serendipitous event that led to the first synthesis of a molecule by the hands of Man in 1826, the creation of molecular matter depended for 150 years on linking together molecules from other molecular building blocks with the help of strong covalent bonds. The advent of supramolecular chemistry in the last decades of the 20th century has provided chemists with a wealth of new possibilities to synthesize molecular structures and materials that are held together by relatively weak, non-covalent interactions, such as hydrogen bonding, π–π stacking, electrostatic and van der Waals interactions. Using nature as a source of inspiration, the creation of even more complex supramolecular architectures has recently become possible by applying the concept of hierarchical self-assembly, i.e. the non-covalent organization of molecules and macromolecules which takes places over distinct multiple levels, in which the assembly processes gradually decrease in strength. This review will focus on some recent discoveries in the field of spontaneous hierarchical organization of synthetic amphiphiles, disk-like molecules and concave building blocks into well-defined nano-sized assemblies.

Mastering molecular matter. Supramolecular architectures by hierarchical self-assembly

Synthetic routes to multiporphyrin arrays.

Poly- and oligometalloporphyrins associated through coordination

Self-assembly of metallopyridylporphyrin oligomers

A new type of porphyrin array has been synthesized by the coupling of six porphyrin moieties to a central benzene core via an ether linkage. The resulting porphryin supermolecule has a diameter up to 80 A and a mass of 8500 daltons. In solution, the six porphyrins around the central benzene ring arrange themselves into three sets of offset overlapping dimers, which are rapidly interconverting at room temperature. Solution UV−vis and fluorescence studies, however, indicate that there are no electronic interactions between the individual porphyrin molecules. Upon spreading a chloroform solution of these porphyrin molecules on a surface, they self-assemble to form ring-shaped architectures on a micrometer scale. Near-field scanning optical microscopy studies reveal that the porphyrin moieties within the rings have an ordered arrangement with respect to their position in the ring after the sample has been annealed at 80 °C for 2 days.

H. A. M. Biemans

Papers

Hexakis porphyrinato benzenes. A new class of porphyrin arrays

Hexakis Porphyrinato Benzenes. A New Class of Porphyrin Arrays.