1D tubular and 2D metal-organic frameworks based on a flexible amino acid derived organic spacer

The organic ligand bgxH(4), resulting from the condensation of two glutamate moieties on a xylene core, has been designed to generate chiral metal-organic frameworks with increased metal-metal distances in order to favor their potential porosity. The in situ reactivity of the ligand, through cyclization, led to the bpgxH(2) ligand, which displays an extremely rich architectural potential. Under formate-generating conditions, two 1D tubular and one 2D MOFs based on bpgxH(2) have been obtained, incorporating up to three different organic linkers, and organized in an exquisite hierarchical way by the combined effects of the flexibility, the coordinating groups, and the H-bonding groups of the ligand. Furthermore, the tubular structures display pockets where water molecules are encapsulated.