Fluorinated Metal Organic Frameworks Research Articles

Structural, Magnetic, and Gas Adsorption Study of a Series of Partially Fluorinated Metal−Organic Frameworks (HF-MOFs)

Four new partially fluorinated metal organic frameworks (HF-MOFs) have been synthesized under different solvothermal conditions (H(2)O or dimethylformamide (DMF)) from transition metal cations [Co(2+) and Mn(2+)], 3-methyl pyridine (3-mepy) and 4,4'-(hexafluoroisopropylidene) bis(benzoic acid) (C(17)H(10)F(6)O(4), H(2)hfbba), to determine the influence of reaction conditions on the formation of MOFs. This family of materials displays a striking degree of structural similarity depending on the solvent of synthesis. HF-MOFs synthesized from H(2)O [Co-HFMOF-W, Co(hfbba)(3-mepy)(H(2)O) and Mn-HFMOF-W, Mn(hfbba)(3-mepy)(H(2)O)] contain three-dimensional connectivity whereas HF-MOFs synthesized from DMF Co-HFMOF-D, [Co(2)(hfbba)(2)(3-mepy)(2)]·(DMF)(3) and Mn-HFMOF-D, [Mn(2)(hfbba)(2)(3-mepy)]·(H(2)O) are two-dimensional in nature. Co-HFMOF-W and Mn-HFMOF-W are iso-structural polymeric materials. Thermal gravimetric analysis performed on as-synthesized HF-MOFs revealed that these compounds have high thermal stability (∼350 °C). The continuous decrease of the χT product with decreasing T for Co-HFMOF-D and Co-HFMOF-W respectively indicates the presence of antiferromagnetic exchange interaction between two Co(2+) (S = 3/2) metal centers within a cluster.

Solvothermal Synthesis, Structure, and Properties of Metal Organic Framework Isomers Derived from a Partially Fluorinated Link

Solvothermal reactions of Cu(NO3)2·3H2O with 4,4′-(hexafluoroisopropylidene) bis(benzoic acid) (C17H10F6O4, H2hfbba) and terminal monodentate ligand 3-methyl pyridine (3-picoline/3-mepy) in the presence of N,N-dimethyl formamide (DMF) and N,N-diethyl formamide (DEF) solvents gave rise to two structurally different two-dimensional (2D) fluorinated metal organic frameworks (F-MOFs). The effect of the choice of solvent has been clearly reflected in the structures obtained. The F-MOFs reported in this paper are formulated as [Cu2(hfbba)2(3-mepy)2]·(DMF)2(3-mepy) (F-MOF-4), [Cu2(hfbba)2(3-mepy)2] (Cu-F-MOF-4B), and [Zn2(hfbba)2(3-mepy)2]·(3-mepy) (Zn-F-MOF-4B) which displays interesting 2D structures with and without interdigitation depending on the solvent used. The structures of these F-MOFs have been determined by X-ray crystallography and further identified by IR spectroscopy, powder X-ray diffraction (PXRD), and thermogravimetric analysis (TGA). The effect of interdigitation has been reflected in the gas ...

Structural Diversity in Partially Fluorinated Metal Organic Frameworks (F-MOFs) Composed of Divalent Transition Metals, 1,10-Phenanthroline, and Fluorinated Carboxylic Acid

Seven new partially fluorinated metal−organic frameworks (F-MOFs) have been synthesized under different solvothermal conditions (H2O or N,N-dimethylformamide (DMF)) from transition metal cations [Zn(II), Co(II), and Mn(II)], 1,10-phenanthroline (phen), and 4,4′-(hexafluoroisopropylidene) bis(benzoic acid) (C17H10F6O4, H2hfbba) to determine the influence of reaction conditions on the formation of metal−organic frameworks. This family of materials displays a striking degree of structural similarity depending on the solvent of synthesis. Of the seven materials, two contain three-dimensional connectivity: Co3(hfbba)6(phen)2 (F-MOF-6) and Mn3(hfbba)6(phen)2 (F-MOF-10). Three materials are one-dimensional structures: Zn(hfbba)0.5(phen)(HCO2) (F-MOF-8), Mn(Hhfbba)2(phen) (F-MOF-11), and [Mn(hfbba)2(dm-phen)]·(H2O) (F-MOF-11A). Lastly, Co(hfbba)(phen)2·2(H2hfbba)(H2O)(HCO2) (F-MOF-7) and Zn(hfbba)(phen)2·2(H2hfbba) (H2O)(HCO2) (F-MOF-9) are discrete zero-dimensional molecular complexes. F-MOF-6 and -10, which fea...

Synthesis and structural comparisons of five new fluorinated metal organic frameworks (F-MOFs)

A series of fluorinated metal–organic frameworks (F-MOFs) have been successfully synthesized under hydrothermal condition using 4,4′-(hexafluoroisopropylidene) bis(benzoic acid) (C17H10F6O4, H2hfbba) as a flexible dicarboxylate building block, Cu+2 and various heterocyclic co-ligands. These F-MOFs formulated as [Cu(hfbba)(phen)2]·2(H2hfbba)(H2O)(HCO2) (F-MOF-1), [Cu(hfbba)2(2,2′-bipy)2(H2O)] (F-MOF-2), [Cu(hfbba)(4,4′dime-2,2′-bipy)(HCO2)]·(hfbba)(H2O) (F-MOF-3), [Cu2(hfbba)2(3-mepy)2]·(DMF)2(3-mepy) (F-MOF-4), and [Cu(hfbba)2(phen)2]·0.5(DMF) (F-MOF-5) (hfbba = 4,4′-(Hexafluoroisopropylidene) bis(benzoate), phen = 1,10-phenanthroline; 2,2′-bipy = 2,2′-bipyridine; 4,4′dime-2,2′-bipy = 4,4′dimethyl 2,2′-bipyridine; 3-mepy = 3-methyl-pyridine and DMF = dimethyl formamide) display interesting H-bonded, 1D and 2D structural features. All these F-MOFs were structurally determined by single-crystal X-ray diffraction. F-MOF-1 and 5 form a distorted octahedral Cu+2 secondary building unit (SBU). F-MOF-5 forms a one-dimensional architecture constructed from Cu2+ ions bridged by phen anions and two types of 4 hfbba ligands while in F-MOF-1, two among the three acid co-ligands are not coordinated with Cu2+ ions. F-MOF-2 displays dinuclear SBUs within the three-dimensional frameworks whereas F-MOF-3 displays mononuclear SBUs and forms a one-dimensional chain. F-MOF-4 display a interesting 2D framework with conventional Cu2(CO2)4 paddle wheel SBU. In the crystal structures four hfbba ligands, each coordinated to a dicopper paddlewheel unit via one of their carboxylate groups. Solid-state properties such as UV-vis and thermal stability of F-MOF-1–5 have also been studied.