Ag(I) and Cu(II) Discrete and Polymeric Complexes Based on Single- and Double-Armed Oxadiazole-Bridging Organic Clips

Abstract

Four new oxadiazole-bridging ligands (L1-L4) were designed and synthesized by the reaction of 2,5-bis(2-hydroxyphenyl)-1,3,4-oxadiazole with isonicotinoyl chloride and nicotinoyl chloride, respectively. L1 and L3 are unsymmetric single-armed ligands (4- or 3-pyridinecarboxylate arm), and L2 and L4 are symmetric double-armed ligands (4- or 3-pyridinecarboxylate arms). Nine new complexes, [Ag(L1)]PF6.CH3OH (1), [Ag(L1)]ClO4.CH3OH (2), Cu(L2)(NO3)2.2(CH2Cl2) (3), [Cu(L2)2](ClO4)2.2(CH2CCl2) (4), Cu(L2)Cl2 (5), [Cu4(L3)2(H2O)2](L3)4(ClO4)4 (6), [Ag(L4)(C2H5OH)]ClO4 (7), [Ag(L4)(C2H5OH)]BF4 (8), and [Ag(L4)(CH3OH)]SO3CF3 (9), were isolated from the solution reactions based on these four new ligands, respectively. L1, L2, and L3 act as convergent ligands and bind metal ions into discrete molecular complexes. In contrast, L4 exhibits a divergent spacer to link metal ions into one-dimensional coordination polymers. New coordination compounds were fully characterized by infrared spectroscopy, elemental analysis, and single-crystal X-ray diffraction. In addition, the luminescent and electrical conductive properties of these new compounds were investigated.

Coordination-directed one-dimensional coordination polymers generated from a new oxadiazole bridging ligand and HgX2(X= Cl, Br and I)

“…So far, various organic ligands have been used for molecular helical building blocks, but 1,3,4-oxadiazole-based bent organic ligands as a helical component have remained rare until recently. Previously, a study of the Ag I coordination chemistry of 2,5-bis[3-(3-pyridylcarbonyl)phenyl]-1,3,4-oxadiazole (L4; Dong et al, 2006) found that L4 and Ag I can be employed as angular directional components to give rise to a helical skeleton, which could be considered as an alternative rational approach to accessing helical metal-organic polymers. As part of our systematic investigation of self-assembly based on bent ligands of this type, we have synthesized a new 1,3,4oxadiazole bridging bent ligand, 2,5-bis{5-methyl-2-[(4-pyridyl)methoxy]phenyl}-1,3,4-oxadiazole, L or (I), and three novel metal-organic frameworks with the same architectures and topologies, [(HgLCl 2 )ÁCH 3 OH] n , (II), [(HgLBr 2 )ÁCH 3 -OH] n , (III), and [(HgLI 2 )ÁCH 3 OH] n , (IV), the structures of which we report here.…”

“…The two terminal pyridine rings and the central oxadiazole ring of (I) are almost coplanar, with dihedral angles between the planes of the pyridine and oxadiazole rings of 5.994 (7) and 9.560 (6) . Compared with L4 (Dong et al, 2006), the methylene group in (I) is more flexible than the carbonyl group in L4, making (I) more attractive for the design of novel supramolecular complexes.…”

Crystal structure and anti-inflammatory activity of (3E,5E)-1-((4-bromophenyl)sulfonyl)-3-(pyridin-4-ylmethylene)-5-(2-(trifluoromethyl)benzylidene)piperidin-4-one, C25H18BrF3N2O3S

“…In addition, the N-phenylsulfonyl substituents are going to stretch in the direction of the carbonyl group of the central piperidone. The title compound looks like an "organic clip" [15,16]. The dihedral angle between the mean plane of the N-phenylsulfonyl and the mean plane of the piperidone ring is 42°.…”

Synthesis, structure and luminescence of novel co-crystals based on bispyridyl-substituted α , β -unsaturated ketones with coformers

“…3, the bent resorcinol template as the hydrogen bonding donor looks like an ''organic clip'' [24,25] with two group OAHÁ Á ÁN hydrogen bonds from two pyridine groups in co-crystal 1-3. Relevant hydrogen-bonding geometries are given in Table 3.…”