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Four mixed-ligand silver(I) coordination polymers (CPs) {Ag2(tpyz)(L)}_n ( 1 ), {Ag4(tpyz)2(L)2}_n ( 2 ), {Ag2(mpyz)(L)}_n ( 3 ) as well as its isomer ( 4 ), (tpyz-2,3,5-trimethylpyrazine, mpyz = 2,3,5,6-tetramethylpyrazine, H2L = (+)-camphoric acid), were synthesized with reactions of L and pyrazine derivatives with silver nitrate in different solvent systems. Systematic characterizations with single-crystal X-ray diffraction indicate that, 1 and 3 show a 3D framework which constructed by silver(I) and L anion, the pyrazine derivatives only give one N to connect to metal, which may be due to the disorder of the methyl which shares the same carbon with carboxylate; 2 and 4 demonstrate a 2D 4 4 –sql network. The difference between two: one structure is single layer and the other is double layer. Furthermore, 4 contains a 1D helical chains which connected by Ag(I) and mpyz ligand. Meanwhile, the L anion exhibits different coordination modes in 1 – 4 . 1 – 4 spanning from two-dimensional network to three-dimensional framework suggest that the kinds of pyrazine derivatives and solvents play significant roles in the formation of such coordination architectures. The thermogravimetric analyses (TGA), IR, and photoluminescence were also measured. [ABSTRACT FROM AUTHOR]

Six coordination compounds of Ag(I) and 2,4-diamino-6-[2-(2-methyl-1-imidazolyl)ethyl]-1,3,5-triazine (L, Ag:L = 1:2) with different anions and solvents, namely, [Ag(L) 2 ]∙(NO 3 )∙4(H 2 O) ( 1 ), [ Ag ( L ) 2 ] · 1 / 2 ( nds ) · ( MeOH ) · ( H 2 O ) ( 2 , H 2 nds = 1,5-naphthalenedisulfonic acid), [ Ag ( L ) 2 ] · 1 / 2 ( nds ) · ( MeOH ) · 5 / 2 ( H 2 O ) ( 3 ), [ Ag ( L ) 2 ] · 1 / 2 ( nds ) · ( CH 3 CN ) ( 4 ), [Ag(L) 2 ]∙(ClO 4 )∙(MeOH)∙(H 2 O) ( 5 ), and [Ag(L) 2 ]∙(ClO 4 )∙2(H 2 O) ( 6 ), have been synthesized and characterized by elemental analysis, IR, PXRD and X-ray single-crystal diffraction. In these compounds, each Ag(I) ion is ligated by two imidazole nitrogens to form a Ag(L) 2 unit. The anions and solvents determine hydrogen-bonding between the DAT groups links the Ag(L) 2 units whether to form chains in 1 and 2 or layers in 3 – 6 . In addition, thermogravimetric analysis (TGA) and luminescent properties of these compounds were also investigated. [ABSTRACT FROM AUTHOR]

Achiral ligand- and Ag(i)-driven spontaneous resolution occurred simultaneously in the formation of two enantiomers 1P and 1M of [Ag2(5-nip)(mpyz)] (5-nip = 5-nitroisophthalic, mpyz = 2,3,5,6-tetramethylpyrazine), whose absolute sense of a helix made of achiral components is induced by the metal Ag(i) through argentophilic interactions. [ABSTRACT FROM AUTHOR]

Achiral ligand- and Ag(i)-driven spontaneous resolution occurred simultaneously in the formation of two enantiomers 1P and 1M of [Ag2(5-nip)(mpyz)] (5-nip = 5-nitroisophthalic, mpyz = 2,3,5,6-tetramethylpyrazine), whose absolute sense of a helix made of achiral components is induced by the metal Ag(i) through argentophilic interactions. [ABSTRACT FROM AUTHOR]

Five one-dimensional to three-dimensional coordination polymers have been synthesized by 2-chlorobenzoic acid (HL 1 ), 2-nitrobenzoic acid (HL 2 ), o-toluic acid (HL 3 ), 2,3,5-trimethylpyrazine (tpyz) and 2,3,5,6-tetramethylpyrazine (mpyz) in the presence of NH 3 ·H 2 O in mixed solvents systems, namely, {Ag 4 (tpyz) 2 (L 1 ) 4 } n ( 1 ), {Ag 2 (tpyz) (L 2 ) 2 } n ( 2 ), {Ag 2 (tpyz) (L 3 ) 2 } n ( 3 ), {Ag 2 (mpyz) (L 1 ) 2 } n ( 4 ), {Ag(mpyz) (L 2 ) (H 2 O)} n ( 5 ). All the complexes have been characterized by elemental analyses, IR spectra and X-ray diffraction. Compound 1 shows a 3D framework. The tpyz ligand links 1D chain which was connected by silver atom and L 1 anion into 3D framework. Compounds 2 and 4 possess a similar 2D network with (4, 4) topology. Complex 3 also exhibits a two-dimensional structure. There is a 1D silver chain in 3 , which is the main difference from 2 and 4 . So, 3 shows three-connected (4 8, 3) topology. For 5 , only one oxygen of L 2 coordinated to Ag(I) ions. The L 2 anions were arranged in both sides of the chain, which was connected by silver atoms and mpyz ligands. Then, the uncoordinated carboxylate oxygen with coordinated water 1 molecule oxygen through the hydrogen bond made the resultant structure to a 3D framework. Complexes 1 – 5 spanning from one-dimensional chains to three-dimensional framework suggest that carboxylates and the kinds of pyrazine derivatives play significant roles in the formation of such coordination architectures. The photoluminescence and thermogravimetric analysis (TGA) of the complexes were also investigated. [ABSTRACT FROM AUTHOR]

Three mix-ligand Ag(I) coordination compounds, namely, {[Ag 10 (tpyz) 5 (L1) 5 (H 2 O) 2 ].(H 2 O) 4 } n ( 1 , tpyz = 2,3,4,5-tetramethylpyrazine, H 2 L1 = phthalic acid), [Ag 4 (tpyz) 2 (L2) 2 (H 2 O)].(H 2 O) 5 } n ( 2 , H 2 L2 = isophthalic acid) {[Ag 2 (tpyz) 2 (L3) (H 2 O) 4 ].(H 2 O) 8 } n ( 3 , H 2 L3 = terephthalic acid), have been synthesized and characterized by elemental analysis, IR, PXRD and X-ray single-crystal diffraction. 1 exhibits a 2D layer which can be simplified as a (4,4) net. 2 is a 3D network which can be simplified as a (3,3)-connected 2-nodal net with a point symbol of {10 2 .12}{10 2 }. 3 consists of linear [Ag(tpyz) (H 2 O) 2 ] n chain. Of particular interest, discrete hexamer water clusters were observed in 1 and 2 , while a 2D L10(6) water layer exists in 3 . The results suggest that the benzene dicarboxylates play pivotal roles in the formation of the different host architectures as well as different water aggregations. Moreover, thermogravimetric analysis (TGA) and emissive behaviors of these compounds were investigated. [ABSTRACT FROM AUTHOR]