Amine-templated assembly of metal-organic frameworks with attractive topologies

Seven new metal-organic frameworks (MOFs) have been synthesized using different organic amines as templates: [Cd(HBTC)(2)]center dot 2(HDETA)center dot 4(H2O) (1) (BTC = 1,3,5-benzenetricarboxylate and DETA = diethylenetriamine), [Cd-2(BTC)(2)(H2O)(2)]center dot 2(HCHA)center dot 2(EtOH)center dot 2(H2O) (CHA = cyclohexylamine) (2), [Cd-5(BTC)(4)Cl-4]center dot 4(HTEA)center dot 2(H3O) (TEA = triethylamine) (3), [Cd-3(BTC)(3)(H2O)] center dot (HTEA) center dot 2(H3O) (4), [Zn(BTC)(H2O)] center dot (HTPA) center dot (H2O) (TPA = tri-n-propylamine) (5), [Cd(BTC)] center dot (HTPA)center dot (H2O) (6), and [Cd-2(BTC)(HBTC)] center dot (HTBA) center dot (H2O) (TBA = tri-n-butylamine) (7). Topologically, the polymer 1 exhibits a two-dimensional (2D) Cd-HBTC network with (4 4) topology, which is a sql structure; the polymer 2 possesses a three-dimensional (3D) porous Cd-BTC framework with (4 center dot 6(2))(2)(4(2)center dot 6(10)center dot 8(3)) topology, which is a contorted rutile structure; polymer 3 exhibits a 3D open Cd-BTC architecture with (6(2)center dot 8(2)center dot 10(2))(2)(6(2)center dot 8(4))(6(3))(4) topology; polymer 4 is a 3D porous Cd-BTC network with. new (4 center dot 6(2))(2)(4(2)center dot 6(4)center dot 8(6)center dot 10(3))(6 center dot 8(2))(2)(6(2)center dot 8(4))(6(2)center dot 8(4))(2)(6(2)center dot 8)(2) topology; similar to 1, polymer 5 is a 2D Zn-BTC framework with (4 center dot 8(2)) topology; interestingly, polymer 6 possesses a 3D porous Cd-BTC architecture with the same topology as 2; polymer 7 shows a 3D open Cd-BTC framework with (6(3))(6(5)center dot 10) topology. In addition to the structures of polymers 1-7, their thermal stabilities, ion exchange properties, and nonbonding interaction energies, including H-bonding and van der Waals, have also been studied. Remarkably, those organic amine cations reside in the interlayer or channel space, playing important roles such as templating, space-filling, and charge-balancing agents. These studies would facilitate the exploration of novel MOFs with charming molecular topologies and multifunctional properties.