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A series of metal–organic frameworks built from a propionate-functionalized purine-containing ligand 3-(6-oxo-6,9-dihydro-1H-purin-1-yl)propanoic acid (H2L), {[La(HL)3(H2O)2]·2H2O}n (1), {[Ce(HL)3(H2O)2]·4H2O}n (2), [Co(HL)2(H2O)2]n (3), {[Cd(L)(H2O)]·0.5H2O}n (4) and {[Pb(HL)(C2O4)0.5(H2O)]·2H2O}n (5), was synthesized and characterized. Isostructural 1 and 2 have polymeric chain structures further linked into 3-D porous supramolecular frameworks with 1-D open channels through complicated interchain hydrogen bonding interactions. At 77 K and 1 bar, the dehydrated porous materials 1 and 2 show adsorption behaviors with maximum nitrogen uptakes of 14 and 23 mL g−1, respectively. Complexes 3–5 are 2-D coordination polymers but have different topological structures. Metallohelicate 3 has (4,4) nets composed of left- and right-handed metal–organic helices sharing the common metal centers, but metallohelicate 4 possesses (4·82) topology and 5 has 63-topological structure. In 3 and 5, the polymeric layers are further assembled through regular interlayer hydrogen bonding interactions to form 3-D supramolecular frameworks. Additionally, the thermostabilities of 1–5 as well as the magnetism of 3 were also investigated. [ABSTRACT FROM AUTHOR]

An intentionally synthesized chiral terpyridyl ligand S-2(4-(2,6-di(pyridin-2-yl)pyridin-4-yl)-benzylamino)propanoicacid(H2L) was used to construct two chiral NiIIcomplexes,[Ni2(HL)2(N3)(H2O)](N3)·19H2O (1) and [Ni2(HL)2(N3)2]·7H2O (2). Both complexes aredinuclear metallocyclic complexes. The monoanionic form (HL)−of the chiral ligand coordinates to the metal centers in a bichelatingantiparallel fashion to form the metallomacrocycles where the chiralmetallocycles Ni2(HL)2template the formationof a novel chiral 3D zeolite-like water framework with nanometer cagestrapping the metallocycles or anchor chiral water chains in the 1Dchannels of a resulting chiral 3D supermolecule, respectively. [ABSTRACT FROM AUTHOR]

One Co(II) 1D chain coordination polymer {[Co(bpp)2(H2O)2] (bpp)3· (H2O)· (ClO4)2}n (bpp = 1,3-Bis(4-pyridyl)propane) has been synthesized and structurally characterized by single-crystal X-ray analysis. This compound belongs to orthorhombic system with space group Pccn. 1D chains are packed through π -π interactions and linked together by bpp ligands through hydrogen bonds to construct 2D layers. Organic ligand molecules are pillared among these parallel 2D layers to construct a 3D supramolecular inorganic-organic hybrid framework. Organic ligand bpp in this compound exhibits three unusual comformations. Studies on magnetic properties of this compound show that it presents weakly antiferromagnetic behavior. [ABSTRACT FROM AUTHOR]

Four metal–5-bromonicotinate (Brnic) coordination polymers [Fe(Brnic) 2 (H 2 O) 2 ] n ( 1 ), [Ni(Brnic) 2 ] n ( 2 ), [Ni(Brnic)(bpy)(H 2 O) 2 ] n · n (Brnic)·4.5 n H 2 O ( 3 ), and [Co 2 (Brnic) 3 (bpy) 2 (OH)] n · n H 2 O ( 4 ) have been synthesized and structurally characterized (bpy=4,4′-bipyridine). Complex 1 has corrugated (4,4) sheets formed by μ-Brnic ligands and planar nodes Fe(II). As for 2 – 4 , they all built up from Brnic-bridged dinuclear subunits, but have very different structure features. Complex 2 is a twin-like polymer with (4,4) layers formed by twin paddle-wheel [Ni 2 (Brnic) 4 ] subunits. Through the bridge coordination of bpy ligands with dinuclear rings [Ni 2 (Brnic) 2 ] and trigons [Co 2 (Brnic) 3 (OH)], 6 3 -topological cationic layers with nanosized grids of 3 and chiral ladder-type double chains of 4 formed, respectively. Notably, halogen-related interactions play an important role in the formation of 3D metallosupermolecules 1 – 4 . The thermostabilities of all compounds have been discussed in detail. Moreover, the magnetic investigations of 2 and 4 indicate that there exist antiferromagnetic interactions in the paddle-wheel [Ni 2 (Brnic) 4 ] and trigon [Co 2 (Brnic) 3 (OH)] cores, respectively. [ABSTRACT FROM AUTHOR]

An acetate-functionalized purine-containingligand, 2-(6-oxo-6,9-dihydro-1H-purin-1-yl)acetic acid (H2L), and its six new one–three-dimensional (1–3D) coordinationpolymers, [La(HL)2(NO3)(H2O)2]n(1), [Ce(HL)2(NO3)(H2O)2]n(2), [Pb(HL)2(H2O)2]n(3), [Cd(HL)2(H2O)2]n(4), [Cd(L)]n(5), and [Zn(L)]n(6), were synthesizedand characterized. Single-crystal X-ray diffraction analyses revealthat the architectures of complexes 1–6are built from the metal–organic helixes of ligands H2L. The overall structuresrange from the double helical chains of 1and 2, and the 2D helical networks of 3and 4, to the 3D coordination polymers of 5and 6, containing 2D homochiral layers based on 1D metal–organichelixes. In those meso compounds, ligands H2Ldisplay differently anionic states,bridge modes, and especially unsymmetrical configurations with thesharp distortion between the acetate and purin in favor of constructinghelical assemblies as expected. The plentiful hydrogen-bonding sitesand π···π interactions originating fromthe bioactive purin group of ligand H2Lgreatly contribute to the formation of helicalstructures and the structural dimension, showing an intriguing abilityin the supramolecular assembly. At room temperature, complexes 1–6exhibit solid-state photoluminescences,with their emission wavelengths and intensities varying accordingto the central metal ions and the coordination patterns of ligand H2L. Additionally, thethermostabilities of these new complexes have been discussed in detail.In particular, 3D polymers 5and 6haveextra high thermostabilities and stronger blue emissions, indicatingpotential applications in photoluminescent materials. [ABSTRACT FROM AUTHOR]