Indium Porphyrin Frameworks: An Efficient Photocatalytic Platform for Organic Synthesis

Porphyrinic metal-organic frameworks (PMOFs) are a class of hybrid materials consisting of metal-ion clusters bound by porphyin based organic ligands.  Porphyrinic ligands are of particular interest due to their unique photo-, electro-, and catalytic properties. In addition, porphyrins offer a rare example of a four-fold axis of symmetry in organic ligands which is highly desirable for designing new MOF architectures.  Conventional porphyrin ligands for MOF synthesis contain two or four terminal carboxy groups for metal binding.  However, many of these structures require an additional “pillar” molecule  in order to form 3D porous structures, which inherently increases the complexity of the crystallization process. To overcome this, one strategy in ligand design is to maintain the high symmetry and rigidity in the organic linker, yet increase the number of carboxy binding sites, which in effect renders the porphyrinic ligand “self-pillaring.” This presentation will focus on the structural characterization of these novel porphyrinic MOF architectures. In particular, the synthesis and photocatalytic properties of a novel In-based porphyrinic MOF will be discussed in detail. The mechanistic study of the catalytic activity will also be presented.