1,4-benzene dicarboxylate linker

While the thioether-lined MOFs show reversible binding of Hg(II), thiols are more likely to show stronger interactions. The Zr(IV)-based MOF [Zrg04 (OH)4(dmbd)6] (dmbd = 2,5-dimercapto-l,4-benzene-dicarboxylate. Chart 1) has a 12-connected framework with dmbdc linear linkers between Zr604(0H)4 clusters. Tetrahedral-cage cavities within [Zr604(0H)4(dmbd)6] are... 

Bdtard et al. [159] fabricated an MOF membrane by stepwise deposition of reactants. Two-pillared layered MOFs with the general formula [CujLjPJn (L = dicar-boxylate linker, P = pillaring ligand) were selected. For this demonstration, they selected the nonpolar [Cu2(ndc)2(dabco)] (1 ndc = 1,4-naphthalene dicarboxylate dabco = l,4-diazabicyclo(2.2.2)octane and the polar [Cu2(BME-bdc)2(dabco)] ) (2 BME-bdc = 2,5-bis(2-methoxyethoxy)-l,4-benzene dicarboxylate). The framework structure of 1 is shown in Figure 12.11. 

FIGURE12.12 Dicarboxylic acid linkers used in this work left, H2ndc (ndc 1,4-naphtalene dicarboxylate) and right, HjBME-bdc (BME-bdc 2,5-bis(2-methoxyethoxy)-l,4-benzene dicarboxylate). 

Fig. 2 shows the simulated methane adsorption isotherms for a variety of IRMOF materials. In order to judge the performance of the materials, both the amount adsorbed per volume and per mass are shown. The materials with the best volumetric performances are the ones with the smallest linker molecules and therefore the smallest cavities (see Fig. 1 and Table 1). Within the group of the smaller IRMOFs, materials that consist of linker molecules with more carbon atoms (e.g. the dicarboxylate naphthalene linka- of lRMOF-7 compared to the dicarboxylate benzene linker of IRMOF-1) show a better performance, as the additional carbon atoms result not only in an increased surface area but also in strongs interactions between the methane molecules and the cavities. Fig. 2 a also illustrates that the interpenetrated IRMOFs, which have comparable (in the case of IRMOF-15) or even smaller cavities (IRMOF-9), show a similar performance. At higji pressures the differences between the absolute and the excess amount adsorbed become apparent. Whereas the absolute adsorption isotherms start to level off, the excess adsorption isotherms show a maximum, which is expected for any gas above its critical temperature when the increase of the bulk gas density is larger than the increase in the density of the adsorbate (see Eq. (1)). 

Kitagawa and coworkers have recently described an interesting but different host-guest-polymerization concept to synthesize cross-linked polymers such as polystyrene, methylmethacrylate, and vinylacetate with pseudo-crystallinity in non-photochemical route [57]. In order to achieve this, they have first incorporated the cross-linker 2,5-divinyl-benzene-1,4-dicarboxylate (DVTP) into the porous CP [Cu(DVTP)(triethylenediamine)o.5] (51). The host framework containing porous channels with dangling vinyl groups provides a suitable environment for radical polymerization of these monomers as shown in Fig. 31. This is obviously different from photopolymerization by [2+2] cycloaddition reaction. 

AAS = atomic absorption spectroscopy ATOF-MS = aerosol time-of-flight mass spectrometry 2,6-ndc = 2,6-naphthalenedicarboxylate bdc = 1,4-benzenedicar-boxylate bpdc = 1,3,5-benzenetricarboxylate bpydc = 2,2 -bipyridine-5,5 -dicarboxylate btb = 4,4, 4"-benzene-1,3,5-triylbenzoate btc = 1,3,5-benzenetricarboxylate 3D = three-dimensional dabco = l,4-diaza[2.2.2]bicyclo-octane EDX = energy-dispersive X-ray spectroscopy EXAFS = extended X-ray fine structure Fc = ferrocenyl ICP-AES = inductively coupled plasma atomic emission spectroscopy MOF = metal-organic framework PSD = postsynthetic deprotection PSM = Postsynthetic modification PXRD = Powder X-ray diffraction 1,4-ndc = 1,4-naphthalenedicarboxylate SALE = solvent-assisted linker exchange SBU = secondary building unit ... 

Benzene-1,4-dicarboxylic acid (H2bdc) is one of the most commonly utilized ligands in MOF chemistry, being the linker ligand for MOF-5. Deprotonated carboxylic acids or carboxylates are hard donors and are... 

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