(Z)-4,4′-Stilbene dicarboxylic acid, the overlooked metal-organic framework linker

Metal-organic frameworks exhibit a broad and diverse structural portfolio, with rational structural engineering of frameworks becoming increasingly desirable. Fine-tuning the metal-ligand combination offers a simple way to adjust a framework's physical and chemical properties. One route to synthesising frameworks with new physical properties and topologies without altering the chemical composition is through the use of ligand isomers. Whilst trans-stilbene derivatives, such as (E)-4,4 '-stilbene dicarboxylic acid have been exhaustively studied producing numerous unique frameworks, its ligand-originated isomer, cis-stilbene derivative (Z)-4,4 '-stilbene dicarboxylic acid has not. Herein, we describe the synthesis of ten lanthanide (Z)-4,4 '-stilbene dicarboxylic acid frameworks, five possessing non-interpenetrating 2D sheet structures and five microporous 3D frameworks with 1-dimensional pore channels that incorporate internal voids of up to 5.2 angstrom in diameter. These three-dimensional frameworks have a hitherto unrecognised underlying net topology, now registered as lmj1.

Automated summary

Metal-organic frameworks can be fine-tuned by adjusting the metal-ligand combination, and ligand isomers can be used to synthesize frameworks with new properties and topologies. In this study, ten lanthanide frameworks were synthesized using the cis-stilbene derivative ligand, resulting in five 2D sheet structures and five 3D frameworks with microporous channels. These frameworks exhibit a previously unrecognized underlying net topology, designated as lmj1.