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Highlights: [•] Seven new complexes were synthesized and characterized. [•] Complexes 1–5 represent first examples of HMNBT and HAMTD with copper(I) halides. [•] The complexes 1, 5, 6 and 7 exhibit interesting fluorescence in the solid state. [•] THz-TDS of starting materials and complexes were investigated. [•] Our results show several factors can affect the THz spectra of the complexes. [Copyright &y& Elsevier]

Eight silver (I) complexes with P-donor ligands [triphenylphosphine (PPh 3 ), bis(diphenylphosphino)methane (dppm), 1,2-bis(diphenylphosphino)ethane (dppe) and 1,4-bis(diphenylphosphino)butane(dppb)] and mercaptan ligands [3-amino-5-mercapto-1,2,4-triazole (H 2 AMTA), 2-amino-5-mercapto-1,3,4-thiadiazole (HAMTD), 2-mercapto-6-nitrobenzothiazole (HMNBT) and 2-mercapto-5-methyl-benzimidazole (HMMBD)] named by [Ag 2 (PPh 3 ) 4 (HAMTA) 2 ] n ( 1 ), [Ag 3 (dppm) 3 (AMTD) 2 ] 2 (BF 4 ) 2 ·(dppm) ( 2 ), [Ag 3 (dppm) 3 (AMTD) 2 ] 2 (ClO 4 ) 2 ·(dppm) ( 3 ), [Ag 4 (dppm) 4 (MNBT) 2 ](SO 4 )·(H 2 O) ( 4 ), [Ag 4 (dppe) 4 (HAMTA) 2 (AMTA)] ( 5 ), [Ag 2 (dppb) 2 (HAMTD) 2 ](CF 3 SO 3 ) 2 ·2(CH 3 OH) ( 6 ), [Ag 2 (dppb) 2 (HMNBT) 2 ](CF 3 SO 3 ) 2 ( 7 ) and {[Ag(dppb)(HMMBD) 2 ](CF 3 SO 3 )·2(CH 3 OH)·(H 2 O)} n ( 8 ) are characterized by X-ray diffraction, NMR and fluorescence spectroscopy. Complexes 1 and 8 show 2D network structure. Complexes 2 – 5 are multi-nuclear clusters. Complexes 6 – 7 are of di-nuclear structure. In complex 7 , the offset π⋯π interactions between the neighboring benzene rings help to form the 1-D infinite chain. All the emission peaks of these complexes are attributed to ligands-centered [π–π ∗ ] transitions. [ABSTRACT FROM AUTHOR]

The present work describes the synthesis, full characterization and architectural diversity of six new bioactive silver–organic networks, namely the coordination polymers [Ag(bpa) 2 (CF 3 SO 3 )(H 2 O)] n ( 1 ), {[Ag 2 (PPh 3 ) 2 (bpa) 2 ](CF 3 SO 3 )} n ( 2 ), [Ag(bpe)(CF 3 SO 3 )] n ( 3 ), [Ag(bpe)(CF 3 SO 3 )(CH 3 CN)] n ( 4 ), {[Ag(PPh 3 )(μ-bpe)] 1.5 (BF 4 )} n ( 5 ) and [Ag(bpp)(CF 3 SO 3 )(CH 3 CN) 2 ] n ( 6 ), which are generated via a mixed-ligand strategy using 1,2-bis(4-pyridyl)ethane (bpa), 1,2-bis(4-pyridyl)ethene (bpe) or 1,3-bis(4-pyridyl)propane (bpp) as the main building block and triphenylphosphine (PPh 3 ) as an ancillary ligand source. Complexes 1 – 6 were well characterized by IR, 1 H and 31 P NMR spectroscopy, elemental analysis, fluorescence, THz spectroscopy and single-crystal X-ray crystallography. The complexes 1 , 2 and 4 – 6 have a topological network structure. The type and coordination modes of the bipyridine derivatives and the choice of solvent play a key role in defining the dimensionality as well as the structural and topological features of the resulting networks. Analysis of structures revealed that complex 1 possesses a (5 4 , 6 2 ) topological network structure connected through the bridging ligand bpa. Complex 2 has a dinuclear structure and displays a topologically promising architecture connected through hydrogen bonds between the C H groups of aromatic ring and anions. Complexes 3 and 4 possess different 1D infinite chains which are linked by the bridging ligand bpe, and complex 4 can be simplified as having a three-dimensional mesh topology. Complex 5 has a (9 3 , 3 3 ) topological network structure connected through the bridging ligand bpe. Like complex 4 , complex 6 possesses 1D infinite chains through the bridging ligand bpp, which are linked by hydrogen bonds to form a 3D topological network. Complexes 2 and 4 are generated from CH 2 Cl 2 /CH 3 OH (5:5) and CH 3 CN respectively, while the other complexes are obtained from CH 3 CN/H 2 O (5:5). In addition, complexes 1 – 6 exhibit interesting fluorescence in the solid state at room temperature. [ABSTRACT FROM AUTHOR]

Reaction of transition metal(II) salts with 2,2′-biimidazole (H 2 biim) and co-ligands formed a series of new complexes, [M(H 2 biim) 2 (bipy) 2 ](NO 3 ) 2 ·2H 2 O ( 1 – 3 ) (M = Co, Ni, Zn), [Co(H 2 biim) 2 (bipy)](ClO 4 ) 2 ·3H 2 O ( 4 ), {[Cu(H 2 biim) 2 ] 3 (μ-C 3 H 3 O 4 ) 2 (C 3 H 2 O 4 ) 2 }·6H 2 O ( 5 ), [Co(H 2 biim) 2 (H 2 O) 2 ](C 3 H 3 O 4 ) 2 ( 6 ) (bipy = 4,4′-bipyridine, C 3 H 2 O 4 = malonate dianion, C 3 H 3 O 4 = malonate anion). These complexes were characterized by single-crystal X-ray diffraction, and elemental analysis. All complexes except 4 were also characterized by luminescence spectra and thermogravimetric analysis. The crystal packing of these six complexes shows that cationic M(II)(2,2′-biimidazole) fragments are self-assembled to construct the 3D supramolecular networks by hydrogen bonding and π–π interactions. The 3D supramolecular networks are significantly affected by counter anion and co-ligands. In complexes 1 – 3 , there are two sets of (4,4) nets which pass through each other to form inclined 2D interpenetration. Complex 4 is obtained by similar reactions as 1 Compared with 1 , the only difference in 4 with the reactant Co(NO 3 ) 2 ·6H 2 O replaced by Co(ClO 4 ) 2 ·6H 2 O, but it has a very different structure. In 4, the 3D networks containing cavities of 23 × 23 Å is formed. In complex 5 , the uncoordinated waters form an infinite 1D pipe structure which is embedded in the 3D porous network. The acid–water ring and R 2 2 (9) synthons in complex 6 lead to the formation of (4,4) 2D network. [ABSTRACT FROM AUTHOR]

Abstract: The reactions of triphenylphosphine (PPh3) and 4,4′-bipyridine (bipy), 1,2-di(4-pyridyl)ethane (dpa), 1,3-bis(4-pyridyl)propane (bpp) ligands with AgX (X=BF4 and NO2) lead to five new complexes: {[Ag(PPh3)2(bpp)](BF4)} n (1), [Ag(dpa)(BF4)] n (2), {[Ag(PPh3)2(μ-bipy)]2(BF4)2} n (3) and {[Ag(PPh3)2(CH3CN)]2(μ-bipy)}(BF4)2 (4) and [Ag(dpa)(NO2)] n (5). In 1, 2 and 3, the Ag atoms are bridged by pyridyl-containing ligands (bpp, dpa and bipy, respectively) to form infinite chain structure. In 4, the Ag atoms are bridged by bipyridine to form a dinuclear structure. Complex 5 is of layer structure which is formed by silver atoms, oxygen atoms from NO2 − and dpa. All the complexes are characterized by X-ray diffraction, fluorescence and 1H NMR spectroscopy. [Copyright &y& Elsevier]

Three new MOFs were constructed through hydrothermal synthesis, which exhibited high selectivity towards magnesium nitrate among various metal nitrates via fluorescence quenching. • Two Co-MOFs were prepared with fantastic 3D porous structures. • A Cd-MOF was synthesized with a fantastic hexa-nuclear Cd cluster. • All MOFs exhibited high selectivity towards Mg(NO 3) 2 among various metal nitrates. Three new MOFs, namely {Co 2 (Bbi) 2 (A) 2 ·H 2 O} n (1), {Co(Bbi) (B) 2 ·4H 2 O)} n (2) and {Cd 6 (Bbi) 1.5 (L) 6 ·5H 2 O} n (3) [ Bbi = 1,1′-(1,4-butanediyl)bis(imidazole), H 2 L = (anthracene-9,10-endo-succinic acid), H 2 A = (benzopheno-4,4-dicarboxylic acid), H 2 B = (1,2-diethyl ether-4,4′-dibenzoic acid)], have been constructed through hydrothermal synthesis. 1 exhibits a double interpenetrating 3D to 3D cds topology network with point symbol of {65.8}. 2 forms a large 3D channel by ligand Bbi connected 2D adjacent waveform layers, displaying 4-connected net with sql topology defined by the point symbol of {44·62}. A rare hexa-nuclear Cd cluster can be observed in the structure of 3 with a Schläfli symbol of {42·6} 2 {43·103}{43·6·82}{43·63}{44·62} 2 {45·62·82·10}{46} 4. TG analyses indicate the highly thermal stability of 1 – 3. More importantly, MOFs 1 – 3 can be developed as fluorescent sensors, which show high selectivity towards magnesium nitrate among various metal nitrates in CH 3 CN by fluorescence quenching, presenting as promising candidates for chemical sensing. [ABSTRACT FROM AUTHOR]