Synthesis and applications of functionalized iptycenes

Abstract

Iptycenes are popular synthetic motifs used in sensors, membranes, insulators, and more. Unlike most molecules, iptycenes are incapable of packing efficiently due to their rigid, three-dimensional structures. This produces a phenomenon called "internal free volume" which is the unique property they are often employed for. In part I, novel diamino-iptycenes are synthesized for use as cross-linking agents to create stabilized and modifiable Graphene Oxide membranes for separations in harsh conditions. The current protocols for the synthesis of said iptycenes is discussed, including proposals for reaction condition optimizations. In part II, novel alkylated iptycenes are used to create soluble, porous polymers which can undergo further post-polymerization transformations. The synthesis of di-tBu-pentiptycene was easily managed by the reaction of di-tBu-triptycene quinone and anthracene. In contrast, the reaction of di-tBu-triptycene quinone and di-tBu-anthracene to create tetra-tBu-pentiptycene resulted in minimal product formation. During the synthesis of an alternative alkylated iptycene a novel side product was observed and identified to be a reduced pentiptycene. This structure is proposed to have great synthetic value as an intermediate en route to highly substituted pentiptycenes. Sulfur-based pentiptycene monomers were explored as alternatives to traditional oxygen-based monomers to increase available polymerizations. Methods investigated for the synthesis of sulfur-base monomers failed due to the steric requirements of the synthetic intermediate; possible intermediates as essential for pentiptycene substitution are proposed.