Dynamic Molecular Recognition in Solid State for Separating Mixtures of Isomeric Dicarboxylic Acids

Flexible even if constrained: A polyamine host recognizes dicarboxylic acids in solution and in the solid state, with the highest selectivity towards maleic acid, binding it from mixtures with up to five other dicarboxylic acids, including fumaric acid (see picture). Recognition using mechanochemistry is a dynamic process involving intermediate phases, resulting in the same selectivity as achieved by crystallization from solution.