Flexible ligands dicarboxylates

In terms of organic ligands, much of the recent focus has been on connectivity through oxygen atoms of carboxylic acid groups, and there has been a recent review of this field by Rao and colleagues.12 Rigid dicarboxylic acids, such as benzene-1,4-dicarboxy lie acid, have proved very versatile, as have the simple but more flexible aliphatic systems, such as succinic and... 

Fig. 2 Structures of the polytopic ligand molecules based on terpyridine (1,7,8), pyrazolypyiidine (2-4), pyridine-2,6-dicarboxylic acid (5), Schiff base (6), and phenanthroline (9) ligands. Note, that 1-6 and 9 are ditopic ligands (bisligands), and that 7 and 8 are three-head ligands. Structures 4 and 5 are flexible and water-soluble, and the others are all rigid. In molecule 5, when m = 3, it is denoted as L2EO4...

Wang G-H, Li Z-G, Jia H-Q et al (2009) Metal-organic Irameworks based on the pyridine-2,3-dicarboxylate and a flexible bispyridyl ligand syntheses, structures, and photoluminescence. CrystEngComm 11 292-297... 

Xue et al. reported a new 3D chiral MOF [67], using a flexible dicarboxylate ligand, which exhibits an unprecedented, temperature-induced SC-SC transformation involving release of bridging aqua molecules and hehc-ity conversion of the hehcal chains in two directions within the MOF (Figure 65). 

Yang J, Ma J-F, Liu Y-Y, Batten SR (2009) Four-, and six-cormected entangled frameworks based on flexible bis(imidazole) ligands and long dicarboxylate anions. CrystEngComm 11 151... 

Many compounds containing the dicarboxylate [OOC(CH2)nCOO] dianion have been prepared and characterized. In fact, the conformational flexibility of the aliphatic dicarboxylate-type ligands is reflected in the diversity of their connecting modes that lead to novel frameworks. In general, aliphatic... 

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