Synthesis and Structural Flexibility of a Series of Copper(II) Azolate‐Based Metal–Organic Frameworks

Abstract

The reaction of CuCl2·2H2O with three novel ditopic ligands, 2‐methyl‐1,4‐benzeneditetrazolate (MeBDT2–), 4,4′‐biphenylditetrazolate (BPDT2–), and 2,3,5,6‐tetrafluoro‐1,4‐benzeneditriazolate (TFBDTri2–), affords the metal–organic frameworks Cu(MeBDT)(dmf) (1), Cu(BPDT)(dmf) (2), and Cu(TFBDTri)(dmf) (3), respectively. These materials feature a common network topology in which octahedral Cu2+ ions are bridged by azolate ligands and dmf molecules to form one‐dimensional chains. The individual chains are connected by the organic bridging units to form diamond‐shaped channels, in which the solvent molecules project into the pores. The bridging dmf molecules in 1 are readily displaced by other coordinating solvent molecules, which leads to a change in the pore dimensions according to the steric bulk of the solvent. Interestingly, attempts to exchange the analogous solvent molecules in the expanded framework 2 induced no change in the pore size, revealing the rigidity of the framework. Meanwhile, 3 exhibits modest flexibility and an improved thermal stability consistent with its chemical functionality. The marked difference in flexibility highlights the considerable impact the organic linker can have on the dynamic framework properties.

Syntheses, structural characterization and properties of transition metal complexes of 5,5′-(1,4-phenylene)bis(1H-tetrazole) (H2bdt), 5′,5′′-(1,1′-biphenyl)-4,4′-diylbis(1H-tetrazole) (H2dbdt) and 5,5′,5′′-(1,3,5-phenylene)tris(1H-tetrazole) (H3btt)

“…The ligands 5,5¢-(1,4-phenylene)bis(1H-tetrazole) (H 2 bdt) and 5¢,5¢¢-(1,1¢-biphenyl)-4,4¢-diylbis(1H-tetrazole) (H 2 dbdt) were prepared using literature precedents. 81, 82 The ligand 5,5¢,5¢¢-(1,3,5phenylene)tris(1H-tetrazole) (H 3 btt) was synthesized from 1,3,5tricyanobenzene 83 using a modified version of the procedure described in ref. 84.…”

Enhanced selective CO2 adsorption on polyamine/MIL-101(Cr) composites

“…In the last two decades, a large number of metal-organic frameworks (MOFs) have been successfully synthesized. [14][15][16][17][18][19] Among the numerous attractive traits of this new family of solid porous materials are their well-characterized crystalline architectures, ultrahigh porosity and the possibility of functionality. Hence, they have been extensively investigated for the potential application in gas storage and gas separation.…”

Effect of substituent on structures and catalytic properties of cobalt(II) isophthalate coordination polymers with a semi-rigid bis(benzimidazole)

“…The utilization of the flexible ligand 1,1 0 -(1,4-butanediyl)bis(2-methylbenzimidazole) can also result in magnificent 3D frameworks [15e17]. In addition, the 2-position methyl substituent on the benzimidazole ring can greatly enhance the electron-donating ability of the ligand [18]. Furthermore, when searching the Cambridge Structural Database (version 5.37, May 2015) [19] for MOCPs constructed from a semi-rigid 1,2-bis(2-methylbenzimidazol-1-ylmethyl)benzene ligand (L, Scheme 1), scarcely related crystal structures were obtained.…”