Guest-Dependent Cavities in Two-Dimensional Metal−Organic Frameworks Sustained by Tetrafluoro-1,3-benzenedicarboxylate

Five two-dimensional (2D) metal−organic frameworks (MOFs) constructed from Cu(II)-based paddle-wheel secondary building units (SBUs) and 2,4,5,6-tetrafluoro-1,3-benzenedicarboxylate (TFBDC) are reported. These compounds exhibit a distorted tetragonal sheet topology with variable pore structures. Both the intralayer and the interlayer cavities of these MOFs can be tailored as either closed, partially open, or fully open with the aid of appropriate guest species. In addition, the nature and dimension of interstitial spaces can be modified using various axial ligands of SBUs. Crystal-to-crystal transformations (CCT) occur among some of these compounds. Such behavior is attributed to the wide range of possible conformations in TFBDC.