Self-penetrating and interpenetrating 3D metal-organic frameworks constructed from the rigid 1,4-bis(1-imidazolyl)-benzene ligand and aromatic carboxylate

This paper presents four interesting entanglement systems, including one self-penetrating and three interpenetrating frameworks, namely, [Ni-3(L)(3)(BTC)(2)center dot 2H(2)O]center dot 6H(2)O (1), [Mn(L)(HBTC)] (2), [Ni-2(L)(2)(BDC)(2)center dot 2H(2)O]center dot H2O (3), and [Mn-4(L)(4)(BDC)(4)]center dot H2O (4) (H3BTC = 1,3,5-benzenetricarboxylic acid and H2BDC = 1,4-benzenedicarboxylic acid), based on a rigid 1,4-bis(1-imidazolyl)benzene (L) ligand. Compound 1 is the first example of a (3,4)-connected self-penetrating three-dimensional (3D) polymer containing two types of catenated rings with the unprecedented (6 center dot 8(2))(2)(6(2)center dot 8(4))(2)(6(4)center dot 8(2)) topology. Compound 3 has self-assembled into a 5-fold interpenetrating 3D structure with diamond nets, while both compounds 2 and 4 display 2-fold interpenetrating 3D structures with alpha-Po structural topology.