Supramolecular Approaches to Control Reactivity in the Organic Solid State

University Of Iowa, Iowa City IA

Investigators

Abstract

Nontechnical Abstract: The general goal of this project is to increase the value of chemical reactions conducted in the organic solid state. Synthetic chemistry is an underpinning in chemical science that enables advancements in society as related to developing new medicines (e.g. active pharmaceutics) and technologically-important materials (e.g. strong and lightweight). This project will develop strategies to synthesize molecules in which chemical reactions are conducted in the solid state. Whereas synthetic chemistry is typically performed in the liquid phase or solution, the solvent-free and "frozen" environment of the solid state provides opportunities to synthesize molecules with unique structures and properties. Strategies to conduct reactions in organic solids can, thereby, accelerate progress of how synthetic chemistry defines and is applied to developments in society and technology. The project will integrate underrepresented groups, develop undergraduate laboratory experiments, and maintain active collaborations with undergraduate colleges. The project will also introduce middle-school students to careers in chemical science (e.g. X-ray crystallography). Technical Abstract: This project will increase the value of reactions conducted in solids by developing solid-state reactions that generate products with synthetically-valuable organic functional groups and/or are based on reduced symmetries. The research will apply multi-component solids in the form of cocrystals and/or metal-organic materials to direct the solid-state reactions. Specifically, (i) metal-organic solids will direct photodimerizations of imines that form cyclobutanes lined exclusively with aldehyde groups, (ii) cocrystals will direct photodimerizations that generate unsymmetrical ladderanes, and (iii) cocrystals will support cross-photocycloadditions. The research is motivated by the fact that although multi-component solids are rapidly emerging as media to reliably control reactivity in solids relative to the liquid phase, important avenues of needed investigation based on forming products decorated with challenging organic functional groups and of reduced symmetry remain unaddressed. When the proposed research is completed, it will be possible to more broadly apply reactions in solids to problems of organic synthesis (e.g. complex molecules), green chemistry (e.g. solvent-free preparation), inorganic chemistry (e.g. metal-organic reactivity), and materials science (e.g. single-crystal reactions).