Grant: Discovery Grants Program - Individual

The proposed research aims to progress fundamental principles to control chemical reactivity in the organic solid-state with a focus to diversify synthetic supramolecular and molecular approaches. In doing so, we address one of the central challenges in modern chemistry; namely, the development of novel, cleaner, and more efficient synthetic methodologies. We aspire for the organic solid state to be a medium akin to the liquid phase to control covalent bond formation and not only match but exceed the breadth of molecules and polymers achieved using solution chemistry. Our group has pioneered a method to direct the formation of covalent bonds in crystals where we employ templates to control covalent bond formation. The approach utilizes principles of supramolecular chemistry (i.e., hydrogen bonding, halogen bonding, metal coordination) to direct covalent bond formation and, in doing so, deal with vexatious structural effects of crystal packing. For the current proposal, we aim to innovatively advance the organic solid state to direct the [2+2] photocycloaddition reaction. First, we will develop self-assembly processes that combine both hydrogen and halogen bonds. In addition to introducing a novel approach to generate covalent bonds, diversification of the products will be achieved by allowing for different functional groups to be integrated into products. The approach will also allow for possibilities to direct reactions of two different reacting partners. Second, we aim to develop molecular recognition processes of nucleobases to mediate covalent bond formation in crystals. The method will provide the first entry on the use of the base pairing language of DNA to generate molecules in solids. The focus here will be the integration of A/T and A/U base pairing to form simple and complex products (e.g., ladderanes). Third, we will develop metal-ions as catalysis to mediate [2+2] photoreactions in solids. Doing so will not only introduce metals as catalysts to mediate photocycloadditions in solids but will also reduce amounts of toxic metals used to form molecules in crystals. The approach will open ideas to achieve catalytic control of topochemical polymerizations. Collectively, our work will expand the toolbox of methods to reliably form covalent bonds in the solid state, embracing fundamental principles of green chemistry and sustainable materials research. The deliverables will involve advances in crystal engineering and green chemistry, the application of bioinspired forms of molecular recognition in solids, and enablement of metal-based catalysis. The development of organic crystals as media for synthetic chemistry is expected to provide new vistas in organic synthetic chemistry and materials science research, and in doing so greatly contribute to the position of Canada as a leader in chemical innovation and manufacturing. The research will also allow for HQPs to be highly prepared for modern research in academia and industry.