Chang-Cang Huang

Encapsulating Naphthalene in an Electron-Deficient MOF to Enhance Fluorescence for Organic Amines Sensing

Host-guest encapsulation of electron-rich naphthalene molecules into a weakly emissive porous metal-organic framework based on π-electron-deficient (π-acidic) naphthalene diimide tectons leads to orange-emissive crystals, which can be used to sense strongly basic organic amines in a fast response, high photostability, and tunable sensitivity. Moreover, such host-guest inclusion crystals are also a good photochromic probe for the detection of weakly basic N-methyl-2-pyrrolidone and N,N-dimethylformamide molecules.

A 2-D framework incorporating lanthanide metal complex linkers into polymeric iodoplumbate

A 2-D metal–organic hybrid framework, [(Nd2DMF12IN2)(Pb8I20)]n (HIN = isonicotinic acid) was structurally determined, which was constructed from a lanthanide metal complex and 1-D lead–iodine polymersvia a HIN ligand with mixed coordination sites.

From achiral tetrazolate-based tectons to chiral coordination networks: effects of substituents on the structures and NLO properties

Using a hydrothermal synthesis method, the combination of four tetrazolate-yl acylamide tectons bearing substituents of different sizes, 4-nitro-N-(1H-tetrazol-5-yl)benzamide (H-NTBAN), 4-fluoro-N-(1H-tetrazol-5-yl)benzamide (H-NTBAF), N-(1H-tetrazol-5-yl)isonicotinamide (H-NTINA) and N-(1H-tetrazol-5-yl)thiophene-2-carboxamide (H-NTTCA), with cadmium dichloride led to four crystalline coordination networks, named Cd3(NTBAN)6 (1), Cd(NTBAF)2 (2), Cd(NTINA)2 (3) and Cd(NTTCA)2 (4), respectively. The X-ray diffraction analysis revealed that compounds 2, 3 and 4 possess a 3D non-interpenetrated diamondoid framework, while compound 1 is of a 0D trinuclear structure. Wherein, compounds 2, 3 and 4 crystallized in chiral space groups with significant second harmonic generation (SHG) efficiencies. The effects of substituents in the semirigid tetrazole-yl acylamide tectons on the structural topologies as well as on the nonlinear optical properties of the generated coordination networks are discussed.

Delicate modulated assembly of a new kind of trinuclear copper(II) motif governed by N-containing agents

A new kind of trinuclear copper(II) motif [Cu3L] was prepared in situ by adopting a multidentate ligand, N′2,N′2′-bis(2-hydroxybenzoyl)biphenyl-2,2′-dicarbohydrazide (H6L), in the presence of a series N-containing agents. Featuring five different assembly styles, [Cu3L(DMF)2.5(hmta)]·3H2O (1), [Cu3L(DMA)(H2O)(Hmor)] (2), [Cu3L(py)2]·DMF (3), [Cu3L(DMF)(H2O)]·2DMF (4), and [Cu3L(DMA)(H2O)]·0.5DMA (5) (hmta = hexamethylenetetramine, Hmor = morphiline, py = pyridine) were obtained. In these assemblies, the [Cu3L] units are connected with each other into one-dimensional chains via bridging of N-containing agents or via sharing an oxygen atom of L6− to fuse together. Furthermore, the connecting styles are found to be governed by the character of the N-containing agents used, which is discussed in detail. Thermal gravimetric analysis and magnetic measurement of some complexes were performed.

Discrete polynuclear manganese nanorods: syntheses, crystal structures and magnetic properties

Shape-anisotropic nanomaterials with uniform lengths and widths have attracted much interest but few of them are involved in self-assembled manganese complexes. The combination of two redox-active acylthiosemicarbazide ligands with Mn3+ cations leads to two discrete polynuclear Mn nanorods, pentanuclear [Mn5(L3)6][Mn0.7(DMF)1.4(H2O)2.8] (1a) and trinuclear Mn3(L4)3·2DMF (2), whose L3 and L4 represent N-(5-(2-hydroxyphenyl)-1,3,4-oxadiazol-2-yl)benzamide and N-(5-(2-hydroxyphenyl)-1,3,4-oxadiazol-2-yl)-propionamide, respectively, which are in situ synthesized from their acylthiosemicarbazide derivatives in the presence of Mn3+ cations, while the latter are reduced into divalent ones in rod-like moieties. For each pentanuclear anion in 1a, the charge is balanced by a solvated trivalent manganese cation, which can be replaced by two tetramethylammonium cations to yield pure valence compound 1b. Moreover, the magnetic studies reveal all of them possess antiferromagnetic properties.

Synthesis, crystal structures and photochromic properties of two coordination polymers based on a rigid tetracarboxylic acid ligand

Manganese(II) and nickel(II) coordination polymers, [Mn(L)(H2O)2]n (1) and [Ni(L)·14H2O]n (2), have been synthesized from a rigid viologen-based tetracarboxylic acid ligand, 1,1′-bis(3,5-dicarboxyphenyl)-4,4′-bipyridinium dichloride (H4L·2Cl) and the Mn(II)/Ni(II) chlorides. The compounds have been characterized by infrared spectra, elemental analyses, single-crystal and powder X-ray diffraction analyses and thermogravimetric analyses. Compound 1 has a 2D coordination network with uncoordinated carboxyl groups, which further stack into a 3D supramolecular structure by hydrogen-bonding interactions. Compound 2 shows a 3D supramolecular framework with 1D channels along the crystallographic b-axis, formed from zigzag chains through hydrogen-bonding interactions. Both compounds display prominent photochromic and photomagnetic behavior upon light irradiation, suggesting that they may be potential photomagnetic materials.

CCDC 1567017: Experimental Crystal Structure Determination

Related Article: Jian-Jun Liu, Shu-Biao Xia, Liu Teng, Chi-Xian He, Fei-Xiang Cheng, Chang-Cang Huang|2017|Z.Anorg.Allg.Chem.|643|1766|doi:10.1002/zaac.201700291