Templated synthesis of zirconium(iv)-based metal–organic layers (MOLs) with accessible chelating sites

Abstract

Metal-organic layers (MOLs) are of great interest in heterogeneous catalysis, particularly those that can accommodate extraneous metal centres. Here, we demonstrate a two-step preorganisation/delamination synthetic strategy using CuI as a...

Understanding the structural landscape of Mn-based MOFs formed with hinged pyrazole carboxylate linkers

“…This may be partly attributable to hindered rotation in the shorter linkers (lacking the phenyl spacer between the pyrazole and carboxylate donors); the importance of this was recently observed by us in Zr-based MOFs formed with L1 and L1 Me where the chelating pyrazole site was shown not to be able to switch between syn and anti conformations. 27 Additionally, and particularly for L1 Me , the lack of the phenyl spacer brings the pyrazole groups close to the MOF nodes. Given these challenges we turned our attention to a computational approach to improve our understanding of the structure metrics that might allow the target MOF to form and to obtain insight into the possible formation of a MnMOF-1 type structure for shorter and longer links.…”

“…Solvents were dried using literature procedures and degassed with Ar prior to use. The ligands bis-(4-carboxypyrazolyl)methane ( L1 ), 27 bis-[4-(4-carboxyphenyl)pyrazolyl]methane ( L2 ), 28 bis-[4-(4-carboxyphenyl)-3,5-dimethylpyrazolyl]methane ( L2 Me ), 29 bis-[4-(4-carboxyphenylethynyl)pyrazolyl]methane ( L3 ), 30 and bis-[4-(4-carboxyphenylethynyl)-3,5-dimethylpyrazolyl]methane ( L3 Me ) 30 were synthesised as previously reported. The ligands 1,1-methylenebis(3,5-dimethyl-1 H -pyrazole-4-carboxylic acid) ( L1 Me ) 31 and 1,1,2,2-tetrakis[4-(4-carboxyphenyl)pyrazolyl]ethane ( L5 ) 32 have been previously reported and were synthesised with some modifications.…”

“…Recently, we reported the synthesis of Zr-based metal-organic layers (MOLs) using the shorter non-methyl L1 linker. 27 Given the availability of these links and demonstration that one of these materials can undergo facile PSMet, we initially focused our attempts to isoreticulate MnMOF-1 on the shorter links L1 and L1 Me .…”

Atomic-Scale Elucidation of Unusually Distorted Dimeric Complexes Confined in a Zr-Based Metal–Organic Framework

“…In addition, we hypothesized that careful linker design could provide a 3D pore environment suited to stabilizing binuclear complexes. Our previous studies indicated that a tetra-carboxylate linker is required to generate a 3D MOF, as flexible ditopic pyrazole carboxylate linkers exclusively produce 2D metal–organic layers (MOLs) with Zr­(IV) . Considering these design criteria, our linker of choice was 1,1,2,2-tetrakis­[4-(4-carboxyphenyl)-1 H -pyrazol-1-yl]­ethane (L1H 4 ) (Figure ).…”

“…Our previous studies indicated that a tetracarboxylate linker is required to generate a 3D MOF, as flexible ditopic pyrazole carboxylate linkers exclusively produce 2D metal−organic layers (MOLs) with Zr(IV). 40 Considering these design criteria, our linker of choice was 1,1,2,2-tetrakis[4-(4-carboxyphenyl)-1H-pyrazol-1-yl]ethane (L1H 4 ) (Figure 2). 31 Reaction of L1H 4 with ZrCl 4 using a trifluoroacetic acid (TFA) modulator in dimethylformamide (DMF) yielded colorless octahedral crystals suitable for SCXRD (Figure S1).…”