6957-22-8Relevant articles and documents
Selective and reversible adsorption of cationic dyes by mixed ligand Zn(II) coordination polymers synthesized by reactant ratio modulation
Rachuri, Yadagiri,Subhagan, Sreevalsa,Parmar, Bhavesh,Bisht, Kamal Kumar,Suresh, Eringathodi
, p. 898 - 908 (2017)
Dye capture and separation through coordination polymers (CPs) has been a promising research field in recent times due to the toxic and nondegradable nature of organic dyes released into the environment from various industries as well as the reusability of CPs for the said purpose. Here, we report the synthesis and characterization of two mixed ligand CPs {[Zn2(HBTC)2(L)(H2O)2](C2H5OH)3}n (CP1) and {[Zn5(BTC)2(L)3(OH)4(H2O)2](H2O)4(CH3OH)11}n (CP2) (where H3BTC = 1,3,5-benzene tricarboxylic acid and L = 1,4-bis(4-pyridyl)-2,3-diaza-1,3-butadiene) by the stoichiometric variation of the precursors. The crystal structure analysis revealed that CP1 is a 2D network composed of a [Zn2(HBTC)2(H2O)2]n motif linked via terminal nitrogen atoms of L and CP2 is a 3D framework in which symmetrically disposed two-dimensional {[Zn5(BTC)2(L)3(OH)4(H2O)2]}n sheets composed of pentanuclear [Zn5(RCO2)6(μ3-OH)2(μ2-OH)2(H2O)2] SBUs are pillared by L ligands. Adsorption and separation of cationic dyes by CP1 and the solid-state fluorescence properties of both CPs have been investigated. Cationic dyes (RhB, MB, and MV) can be effectively adsorbed by CP1 from their aqueous solution (61%, 90%, and 97%, respectively) while the anionic dye methyl orange (MO) remains uncaptured. Dye desorption studies and CP1 as a column chromatographic filler for the separation of cationic dyes in water have also been demonstrated.
Co-crystals of tetrakis-1,2,3,4-(4′-carboxyphenyl)cyclobutane with dipyridyl spacers: Design and serendipity
Kole, Goutam Kumar,Tan, Geok Kheng,Koh, Lip Lin,Vittal, Jagadese J.
, p. 6190 - 6195,6 (2012)
Tetrakis-1,2,3,4-(4′-carboxyphenyl)cyclobutane (TCCB), a tetracarboxylic acid, has been employed for making co-crystals with linear dipyridyl spacers molecules like 4,4′-bipyridine (4,4′-bpy), 1,2-bis(4′-pyridyl)ethane (4,4′-bpethane), trans-1,2-bis(4′- pyridyl)ethylene (4,4′-bpe) and 1,4-bis(4′-pyridyl)-2,3-diaza-1,3- butadiene (4,4′-bpdb). In the case of 4,4′-bpy, a 2:1 co-crystal was obtained with TCCB having a three dimensional 5-fold interpenetrated dmp network. The diagonal-diagonal interpenetrated isostructural (4,4)-connected 2D networks were obtained in 1:1 co-crystals of TCCB with 4,4′-bpe and 4,4′-bpdb. The (4,4)-connected nets in the 1:1 co-crystal of TCCB with 4,4′-bpethane were found to stack parallel instead of interpenetrating. 1:1 co-crystals were always obtained in the last three cases regardless of molar ratio during co-crystallization, indicating the influence of kinetic factors. The structural diversity and similarities in this series of co-crystals in the context of composition variation and solvent interference are discussed. The serendipitous formation of (4,4)-connected networks is critically compared with designability of the system in presence of synthon competition.
A Water-Stable Twofold Interpenetrating Microporous MOF for Selective CO2 Adsorption and Separation
Pal, Arun,Chand, Santanu,Das, Madhab C.
, p. 13991 - 13997 (2017)
Self-assembly of bent dicarboxylate linker 4,4′-sulfonyldibenzoic acid (H2SDB) and flexible N,N-donor spacer 1,4-bis(4-pyridyl)-2,3-diaza-1,3-butadiene (L) with Co(NO3)2·6H2O forms a twofold interpenetrated {[Co2(SDB)2(L)]·(H2O)4·(DMF)}n, (IITKGP-6) network via solvothermal synthesis with SQL(2,6L1) topology, which is characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis, elemental analysis, powder X-ray diffraction (XRD), and single-crystal XRD. The framework is microporous with a solvent-accessible volume of 25.5% and forms a one-dimensional channel along [1-1 0] direction with the dimensions of -3.4 × 5.0 ?2. As the stability of metal-organic frameworks (MOFs) in the presence of water is a topic of significant importance while considering them for practical applications, this framework reveals its high stability toward water. The desolvated framework shows modest uptake of CO2 (50.6 and 37.4 cm3 g-1 at 273 and 295 K under 1 bar pressure, respectively), with high selectivity over N2 and CH4. Ideal adsorbed solution theory calculations show that the selectivity values of CO2/N2 (15:85) are 51.3 at 273 K and 42.8 at 295 K, whereas CO2/CH4 (50:50) selectivity values are 36 at 273 K and 5.1 at 295 K under 100 kPa. The high CO2 separation selectivity over N2 and CH4 along with its water stability makes this MOF a potential candidate for CO2 separation from flue gas mixture and landfill gas mixture as well.
Construction of one dimensional Co(II) and Zn(II) coordination polymers based on expanded N,N′-donor ligands
Zahedi, Mansoureh,Shaabani, Behrouz,Aygün, Muhittin,Kazak, Canan
, p. 461 - 468 (2018)
Four new 1-D coordination polymers [Zn(acac)2(L1)] n (1), [Co(acac)2(L1)]n (2), [Co(acac)2(L2)]n (3) and [Co(acac)2(L3)]n (4) were afforded by the complexation reaction of appropriate zinc and cobalt metal salts, acetylacetone co-ligand as well as three linear electron rich and bi-functional N,N′-bipyridyl-base ligands of N,N′-bis(pyridin-4-ylmethylene)naphthalene-1,5-diamine (L1), N,N′-bis(pyridin-4-ylmethylene) phenylene-1,4-diamine (L2) and N,N′-bis(pyridin-4-ylmethylene)hydrazine (L3). The structures of these compounds were characterized by FT-IR spectroscopy, elemental analysis, X-ray powder and single crystal X-ray diffractions. X-ray crystallography analyses revealed that these compounds have 1-D linear chain structures a containing {N2O4} metal coordination environment in which the N-donor Lx (x = 1–3) bridges occupy trans positions. The acetylacetone (acac) ancillary ligands control the coordination number of the metal cation and adopt chelating binding mode on octahedral metal center. Furthermore, 1-D chains are held together with their neighboring ones by C–H?O, C–H?π and π-π stacking intermolecular interactions to stabilize 2-D supramolecular networks. The two former cases 1 and 2, containing same L1 spacer ligand generate isomorphous structures. Theoretical calculations invoking electronic properties, frontier molecular orbital description and the strength of interactions between metal ion and coordinated atoms via second order perturbation energies were carried out using natural bond orbital analysis (NBO). Finally, thermal stability of compound 2–4 was examined by thermogravimetric (TGA) analysis.
Spontaneous resolution to absolute chiral induction: Pseudo-kagomé type homochiral Zn(II)/Co(II) coordination polymers with achiral precursors
Bisht, Kamal Kumar,Suresh, Eringathodi
, p. 15690 - 15693 (2013)
It is observed that conglomerate crystallization of achiral precursors yielding racemate metal organic frameworks/coordination polymers (MOFs/CPs) can be driven to absolute homochiral crystallization of the desired enantiomorph by utilizing a suitable chiral induction agent. In a series of crystallization experiments isostructural Zn and Co homochiral CPs (1P, 1M and 2P, 2M) are prepared using the achiral precursors. In the presence of enantiopure camphoric acid, the crystallization process prefers absolute chiral induction over conglomerate formation which is established by single crystal X-ray diffraction and CD spectroscopy.
Synthesis of Highly Stable Porous Metal-Iminodiacetic Acid Gels from A Novel IDA Compound
Chen, Wenjing,Jiang, Yanhong,Ding, Xuesong,Yan, Chaoguo,Han, Baohang
, p. 617 - 623 (2016)
In this work, a novel and simple flexible aromatic multi-carboxylate compound N,N′-(4,4′-biphenylyl) iminodiacetic acid (BP-IDA) was synthesized, with which two new stable metal-IDA gels (denoted as MIG1 and MIG2) with three-dimensional network structures have been prepared successfully by employing Cr3+and Al3+as the metal ions, respectively. The rheological performance was investigated by means of dynamic rheology measurement. The morphology and microstructure were characterized by scanning electron microscopy, transmission electron microscopy, and X-ray diffraction technique. Nitrogen sorption isotherm measurement suggests that the MIG1 aerogel has considerable porosity with the Brunauer-Emmett-Teller specific surface area up to 760 m2·g?1. Owing to easy preparation, good stability, and three-dimensional network structure, the as-prepared metal-organic gels will possess potential applications in separation, catalysis, and drug delivery.
A new pillared Cd-organic framework as adsorbent of organic dyes and as precursor of CdO nanoparticles
Ghomshehzadeh, Samira Gholamali,Nobakht, Valiollah,Pourreza, Nahid,Mercandelli, Pierluigi,Carlucci, Lucia
, (2020)
A new neutral cadmium-organic framework with a pillared layer structure, [Cd3(BTC)2(4-bpdb)2] (H3BTC = benzene-1,3,5-tricarboxylic acid; 4-bpdb = 1,4-bis(4-pyridyl)-2,3-diaza-1,3-butadiene), has been synthesized via solvothermal reaction of cadmium nitrate with the tricarboxylic acid H3BTC and the linear bispyridyl linker 4-bpdb. The complex has been characterized by single crystal X-ray diffraction, showing to possess a 3D porous network of jcr7 topology. The capability of the prepared MOF in adsorbing the organic dyes Congo Red (CR) and Neutral Red (NR), together with kinetics and thermodynamics of their adsorption, have been investigated in detail. The adsorption process was well described by pseudo-first order and pseudo-second order kinetics for CR and NR, respectively. In addition, conversion of the MOF 3D architecture into nano-sized cadmium oxide particles has also been studied.
A luminescent metal-organic framework with pre-designed functionalized ligands as an efficient fluorescence sensing for Fe3+ ions
Farahani, Yeganeh Davoudabadi,Safarifard, Vahid
, p. 428 - 435 (2019)
Metal-organic frameworks are a class of attractive materials for fluorescent sensing. Here, we report the exploration of fluorescent Zn-based amine/azine-functionalized MOF, TMU-17-NH2, ([Zn(NH2-BDC)(4-bpdb)].2DMF; NH2-BDC = amino-1,4-benzenedicarboxylic acid, 4-bpdb = 1,4-bis(4-pyridyl)-2,3-diaza-2,3-butadiene) for highly selective and sensitive detection of Fe3+ in DMF solution. TMU-17-NH2 shows fast recognition of Fe3+ ion with a response time of?3 M DMF solution of Fe3+. Furthermore, the static quenching constant is calculated to be upper than 41,000 M?1 by the fluorescence titration experiment in low concentration of Fe3+. No interferences from 250 μM As3+, Cd2+, Zn2+, Co2+, Ni2+, Cu2+, Pb2+, Mn2+ and Al3+ were found for the detection of Fe3+. The efficient fluorescent quenching effect is attributed to the photoinduced electron transfer between Fe3+ ions and the amino-functionalized ligand in this MOF. Moreover, the introduced azine N donors in the 4-bpdb ligand of TMU-17-NH2 additionally donate their lone-pair electrons to the Fe3+ ions, leading to significantly enhanced detection ability. Furthermore, the regenerated TMU-17-NH2 still has high selectivity for Fe3+ ions, which suggests that the functionalized TMU-17-NH2 is a promising luminescent probe for selectively sensing of Fe3+ ions.
Construction of five dicyanamide based coordination polymers with diverse dimensionality: Synthesis, characterization and photoluminescence study
Das, Anamika,Bhattacharya, Biswajit,Maity, Dilip Kumar,Halder, Arijit,Ghoshal, Debajyoti
, p. 585 - 591 (2016)
A family of dicyanamide bridged compounds namely {[Co(dca)4(2-abim)2]}n(1), {[Ni(dca)4(2-abim)2]}n(2), {[Cd(dca)4(2-abim)2]}n(3), {[Zn(N(CN)2)2(4-bpdb)]}n(4) and {[Cd(N(CN)2)2(4-bpdb)]}n(5); [where dca?=?dicyanamide, 2-abim?=?2-aminobenzimidazole and 4-bpdb?=?1,4-bis-(4-pyridyl)-2,3-diaza-1,3-butadiene] have been synthesized by stirring at room temperature. These compounds have been characterized by single crystal diffraction analysis, infrared spectroscopy (IR) and powder X-ray diffraction (PXRD). Complexes 1–3 are isostructural and exhibit two-dimensional (2D) metal-dca sheet with pendant 2-abim ligand. Compound 4 forms [Zn(N(CN)2)]nchains with a pendent dca and a bridging dca linker, which are further connected by bridging 4-bpdb ligands extending into a 2D layer structure. In case of compound 5 each Cd(II) centers connect with four bridging dca linkers to form [Cd(N(CN)2)]ndouble chains, which are further connected by bridging 4-bpdb ligands extending into a 2D layer structure. Here [Cd2(N(CN)2)] and 4-bpdb spacer are interpenetrated to each other and resemble polyrotaxane-type structures. Photoluminescent properties of compounds 3–5 were also studied and they exhibit nice ligands based photoluminescence properties at room temperature.
Ruthenium(ii)-catalysed 1,2-selective hydroboration of aldazines
Gunanathan, Chidambaram,Pradhan, Subham,Thiyagarajan, Subramanian
supporting information, p. 7147 - 7151 (2021/08/30)
Herein, an efficient and simple catalytic method for the selective and partial reduction of aldazines using ruthenium catalyst [Ru(p-cymene)Cl2]2 (1) has been accomplished. Under mild conditions, aldazines undergo the addition of pinacolborane in the presence of a ruthenium catalyst, which delivered N-boryl-N-benzyl hydrazone products. Notably, the reaction is highly selective, and results in exclusive mono-hydroboration and desymmetrization of symmetrical aldazines. Mechanistic studies indicate the involvement of in situ formed intermediate [{(η6-p-cymene)RuCl}2(μ-H-μ-Cl)] (1a) in this selective hydroboration.
