Rational design and synthesis of porous organic-inorganic hybrid frameworks constructed by 1,3,5-benzenetriphosphonic acid and pyridine synthons

1,3,5-Benzenetriphosphonic acid, H6BTP, 1,3,5-[(HO)(2)OP](3)C6H3, was reacted hydrothermally with copper salts in the absence and presence of 4,4'-bipyridine (bpy) and 4,4'-trimethlyenedipyridine (tbpy) in a 1:1 molar ratio leading to three new organic-inorganic hybrid frameworks. Compound 1, {CU6[C6H3(PO3)(3)](2)(H2O)(8)}(.)5.5H(2)O, has three different copper ions that are interconnected by the highly charged [1,3,5-(PO3)(3)C6H3](6-) anionic moieties. These moieties self-assemble through tetra-copper units to give a cagelike motif with two benzene rings parallel to each other at a distance of 3.531 angstrom which extend along the a axis and link with a grouping of four-coordinated copper units in the b axis direction to give the cross-linked layered structure. In compound 2, {Cu C6H3[PO(OH)O](2)[PO(OH)(2))}(C10H8N2), the copper ions are in square pyramidal geometries and are interconnected via chelating and bridging BTP ligands into layers which are further cross-linked by bpy ligands into a pillared layered architecture.Compound 3, {CU2C6H3[PO(OH)O](2)[PO3](C13H14N2)}(.)3H(2)O(.)0.5HCON(CH3)(2), contains tetra-copper units that are linked by BTP ligands and further linked by tbpy linkers in the c axis direction to produce a large channel-sized 3D framework.