Temperature-controlled spontaneous resolution of enantiomerically threefold interpenetrating arm-shaped MOFs with achiral symmetrical ligands

Hydrothermal reaction of flexible 4,4′-oxybis(benzoic acid) (H2oba), semi-rigid 2,5-bis(4-pyridyl)-1,3,4-thiadiazole (bpt) and Cu(OH)2 led to an interesting 2D → 3D polythreaded architecture of MOF [Cu2(bpt)2(oba)2(H2O)]n·4nH2O (1). Accomplished with the rising synthesis temperature, two chiral MOFs [Cu4(bpt)4(oba)4]n (L-2 and D-2), have been obtained from the congenetic nonchiral precursors upon spontaneous resolution, which represent a rarely example of temperature-induced threefold interpenetrating enantiomerically arm-shaped MOFs constructed from achiral symmetrical ligands.