Separation of Xylene Isomers through Selective Inclusion: 1D → 2D, 1D → 3D, and 2D → 3D Assembled Coordination Polymers via β-Sheets

The separation of xylene,isomers has been achieved through sequential and selective crystallization of coordination polymers of Cu(II) with flexible bis(pyridylcarboxamide) ligand (L). The order of preference for inclusion induced crystallization was Shown to be o-xylene > m-xylene > p-xylene. Although all three xylenes included CPs having distinct;differences in terms of their crystal structures, they all have exhibited a tendency to assemble-via beta-sheet hydrogen bonds to form 3D architectures containing channels. The preferential inclusion of isomers of xylenes was confirmed by single crystal X-ray, 1H NMR, and GC. The bulk purity of xylenes was also confirmed by XRPD patterns.