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 ]·2(HDETA)·4(H 2 O) ( 1 ) (BTC = 1,3,5-benzenetricarboxylate and DETA = diethylenetriamine), [Cd 2 (BTC) 2 (H 2 O) 2 ]·2(HCHA)·2(EtOH)·2(H 2 O) (CHA = cyclohexylamine) ( 2 ), [Cd 5 (BTC) 4 Cl 4 ]·4(HTEA)·2(H 3 O) (TEA = triethylamine) ( 3 ), [Cd 3 (BTC) 3 (H 2 O)]·(HTEA)·2(H 3 O) ( 4 ), [Zn(BTC)(H 2 O)]·(HTPA)·(H 2 O) (TPA = tri- n -propylamine) ( 5 ), [Cd(BTC)]·(HTPA)·(H 2 O) ( 6 ), and [Cd 2 (BTC)(HBTC)]·(HTBA)·(H 2 O) (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 (4·6 2 ) 2 (4 2 ·6 10 ·8 3 ) topology, which is a contorted rutile structure; polymer 3 exhibits a 3D open Cd-BTC architecture with (6 2 ·8 2 ·10 2 ) 2 (6 2 ·8 4 )(6 3 ) 4 topology; polymer 4 is a 3D porous Cd-BTC network with new (4·6 2 ) 2 (4 2 ·6 4 ·8 6 ·10 3 )(6·8 2 ) 2 (6 2 ·8 4 )(6 2 ·8 4 ) 2 (6 2 ·8) 2 topology; similar to 1, polymer 5 is a 2D Zn-BTC framework with (4·8 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 ·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.