| Certain applications of supramolecular porphyrinic systems, such as molecular sieves and photonics, rely on precise nanoarchitectural control of the molecules and/or atoms; therefore they require self-assembled systems of discrete arrays and highly ordered crystals.;In this work we investigate functional materials wherein the function derives from the assembly---electron and energy transfer are examples. Recognition groups based on hydrogen bonding are generally designed to efficiently form intermolecular interactions between two or more molecules. The two complementary recognition groups used here are: uracyl (U) and 2,6-diacetaminopyridine (P) derivatives. Attaching two copies of these recognition motifs to the opposite sides of meso aryl porphyrins (free base and metallo) allow these to self-assemble or self-organize via triple hydrogen bonds. These structural and functional studies may serve as a basis for understanding the photo physical properties of the self-organized aggregates.;The use of porphyrins for self-assembly and self-organization of molecules and ions to create functional photonic materials has been cornerstone of much research because of their structural rigidity, chemical stability and rich photo and electro chemical properties. Herein we report the self-assembly of squares formed from four 5,15-bis- (4-pyridyl)-10,20-bis-(4-dodecyloxyphenyl) porphyrin linked together by coordination to cis-platinum (II) dichloride.;Colloidal porphyrin nanoparticles can be considered self-organized systems that are governed by the principles of supramolecular chemistry. Nanoparticles, a unique subset of the broad field of nanotechnology, play an important role in a wide variety of fields including advanced materials, pharmaceuticals, and environmental detection and monitoring. Porphyrin and metalloporphyrin nanoparticles are promising components for advanced material chemistry because of the rich photochemistry, stability, and catalytic activity. The formation and characterization of these nanoparticles are discussed using different techniques (e.g. UV-Vis, Fluorescence, DLS and AFM). These nanoparticles on hydrophilic surfaces de-aggregate into 10-300 nm particles and we observed that different hydrocarbon substituents and metals affect particle size. These systems can serve as sensors and other photonic devices, but my particular focus is on the catalytic properties of nanoparticles of an iron porphyrin. Using gas chromatography coupled with mass spectrometry and hydrogen and oxygen isotope experiments we discovered that these systems have different reactivity than the same porphyrin in solution and that the turnovers are more than 10-fold greater. |
