69506-92-9Relevant articles and documents
Synthesis and Characterization of a Cu2(pzdc)2(bix) [pzdc: 2,3-pyrazinedicarboxylate; Bix: 1,3-bis(imidazol-1-yl)benzene] Porous Coordination Pillared-Layer Network
Arrieta-Pérez, Rodinson R.,Primera-Pedrozo, José N.,Exley, Jason,Hernández-Maldonado, Arturo J.
, p. 1676 - 1685 (2018)
A porous coordination polymer (PCP) was prepared using pyrazine-2,3-dicarboxylate (pzdc) and the pillar ligand 1,3-bis(imidazol-1-yl)benzene) (bix) in an attempt to improve on the thermal stability and adsorption properties of Cu2(pzdc)2(L) (L = pillar ligand; typically dipyridyl-based). As-synthesized Cu2(pzdc)2(bix) showcases a highly crystalline structure (Monoclinic, P21/c, a = 11.836 ?, b = 13.005 ?, c = 11.389 ?, β = 107.64°) that exhibits characteristic diffraction peaks also found in the dipyridyl-based PCP counterparts. Thermal analysis based on results from thermal gravimetric analysis (TGA), differential scanning calorimetry (DSC) and in situ high temperature X-ray diffraction (XRD) suggests both framework contraction and expansion during the elimination of physisorbed and coordinated water, phase transition, and prior to the eventual destruction of the structure, which takes place at ca. 556 K. The thermal stability limit is an improvement over those displayed by other Cu2(pzdc)2(L) materials by an average margin of ca. 55 K. Comparison of the adsorption of CO2 vs N2 both at cryogenic temperatures suggests a concomitant structural expansion in the presence of the former. This process appears to take place even at ambient temperatures and CO2 pressures up to 50 atm; the isotherm profile showcases a hysteretic pathway and full adsorption saturation is not apparent. Furthermore, evaluation of CO2 adsorption at different equilibration time intervals indicate that the structure relaxation time scale is larger than that of the adsorption kinetics; similar observations have been made before for Cu2(pzdc)2(bpy) (bpy: 4,4′-bipyridine). The presence of the imidazole groups, however, results in greater interactions with CO2 (maximum ΔHiso ～ 32 kJ mol-1). Selectivity for CO2 over CH4 (10/90) based on the Ideal Adsorbed Solution Theory (IAST) reaches 8.4, which is a 10% and 75% increase when compared against Cu2(pzdc)2(bpy) and Cu2(pzdc)2(bpe) (bpe: 1,2-di(4-pyridyl)-ethylene).
Assembly of a series of coordination polymers built from rigid a tetracarboxylate ligand and flexible bis(imidazole) linker: Syntheses, structural diversities, luminescence sensing, and photocatalytic properties
Zhang, Xiu-Tang,Chen, Hong-Tai,Li, Bin,Liu, Guang-Zeng,Liu, Xin-Zheng
, p. 1202 - 1213 (2018/02/07)
Hydrothermal reactions of aromatic terphenyl-4,2′′,5′′,4′-tetracarboxylic acid (H4tta) and transitional metal cations in the presence of two flexible N-donor ancillary ligands afforded four novel coordination polymers, namely, {[Zn(tta)0.5(m-bimb)]·H2O}n (1), [Ni2(tta)(m-bimb)2(H2O)]n (2), [Ni(H2tta)(o-bimb)·H2O]n (3), and [Cd(tta)0.5(o-bimb)]n (4), from solvothermal reactions in the presence of bis(imidazole) bridging linkers (m-bimb = 1,3-bis(imidazol-1-ylmethyl)benzene, and o-bimb = 1,2-bis(imidazol-1-ylmethyl)benzene). Their structures were determined by single-crystal X-ray diffraction analyses and further characterized by elemental analyses (EA), powder X-ray diffraction (PXRD), and thermogravimetric (TG) analyses. Compound 1 displayed a 2-fold 3D → 3D parallel entangled (4,4)-connected bbf net with the point symbol of (64·82)(66)2. Compound 2 featured a predocumented 3D (4,8)-connected (32·53·6)(34·44·59·611) net. Compound 3 exhibited a 2D 4-connected SQL sheet with the point symbol of (44·62), and compound 4 showed a 2D 4-connected (32·62·72) kgm sheet. To our delight, fluorescence measurements showed that compound 1 could selectively and sensitively detect Cr3+ cations and nitrobenzene derivatives (nitrobenzene (NB), p-nitrotoluene (PNT), and p-nitroaniline (PNA)), which suggested that CPs of 1 was a promising bifunctional luminescence sensor material that could sense metal ions and small organic molecules. Moreover, 1 showed excellent photocatalytic activity.
Insights into the Formation and Structures of Molecular Gels by Diimidazolium Salt Gelators in Ionic Liquids or “Normal” Solvents
Rizzo, Carla,D'Anna, Francesca,Noto, Renato,Zhang, Mohan,Weiss, Richard G.
supporting information, p. 11269 - 11282 (2016/08/03)
Insights are provided into the properties of molecular gels formed by diimidazolium salts both in “normal” solvents and ionic liquids. These materials can be interesting for applications in green and sustainable chemistry in which ionic liquids play a sig
