Nanotubular Metal-Organic Frameworks with High Porosity Based on T-Shaped Pyridyl Dicarboxylate Ligands

Two nanotubular metal organic frameworks (MOFs), {Cu(L1)center dot 2H(2)O center dot 1.5DMF}(infinity) (1) and {Cu-2(L-2)(2)(H2O)(2)center dot 7H(2)O center dot 3DMF}(infinity) (2), with novel topologies have been constructed based on Cu2+, 5-(pyridin-4-yl)isophthalic acid (L1) and 5-(pyridin-3-yl)isophthalic acid (L2), respectively. Two MOFs were characterized by IR spectroscopy, thermogravimetry single-crystal, and powder X-ray diffraction methods. Network analysis reveals a two-nodal (3,6)connected (4.6(2))(2)(4(2).6(10).8(3)) net and a three-nodal (3,4)-connected (4.8(2))(4)(4(2).8(2).10(2))(2)(8(4).12(2)) net. Interpenetration is inherently prevented by both of the topologies of the frameworks. The porosity of MOF 1 was confirmed by N2 and CO2 gas adsorption investigations. MOF 1 exhibits remarkable hydrogen sorption hysteresis at low pressure and a H-2 uptake capacity of 1.05 wt % at 77 K and 1 atm.