The Macromolecular, Supramolecular and Nanochemistry Program at the National Science Foundation supports the work of Professor Linda Shimizu of the University of South Carolina that investigates the utility of functional porous crystals to absorb, transport and organize guests and to facilitate their subsequent photoreactions. These porous crystals are made by the self-assembly of bis-urea macrocycles into columnar structures. The columns pack close together to give crystals with homogeneous channels with diameters of 1 nm or less. The mobility of the guest through cylinder like nanochannels is a function of the dimensions (size, shape) and interior properties (polarity) of the channel. The Shimizu group studies photoreactions and oxidations in these small spaces. These reactions provide controlled model systems to test the effects of confinement on reactions.
Fundamental understanding of the processes of absorption, diffusion, and storage in tiny straw-like channels with diameters of 1 nm or less has practical application in separations and catalysis. Ultimately, a better understanding of a reaction mechanism aids in the development of safer, more environmentally friendly and economical reagents for organic synthesis. This research provides training for undergraduates and graduate students in organic and materials chemistry. In addition, this award supports the continuation of a chemical demonstration program that brings chemists into South Carolina K-12 classrooms to showcase the scientific method and to foster interest in chemistry and in the natural sciences.
