Diverse Multi-Functionalized Oligoarenes and Heteroarenes for Porous Crystalline Materials

A modular synthesis of multi-functionalized biphenyl, terphenyl and higher linear oligophenylene dicarboxylic acids and pyridine-terminated oligoarenes by stepwise palladium–catalyzed borylation/Suzuki–Miyaura cross-coupling reactions is described. The presence of several distinct functional groups such as azide, hydroxy, and alkyne, as well as coordinative functional end groups (carboxylic acid or pyridine) combined in a single oligoarene molecular unit at strategic positions offer an advantageous dual-utility. First, these compounds can serve as useful molecular bricks (ditopic organic linkers) in the construction of complex porous crystalline materials. Second, after the assembly into the crystalline coordination networks, orthogonal functional sites within the linker-backbone offer tremendous potential from application perspectives as they can be modified by a wide range of post-synthetic modifications including azide–alkyne click chemistry. This allows further tailoring of the supramolecular assemblies to yield novel multifunctional materials.