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Three Cu(I)-cyanide coordination polymers based on trigonal 1,3,5-tris(1H-imidazol-1-yl)benzene (tib) ligand, namely [Cu 3 (CN) 3 (tib)] n ( 1 ), [Cu 4 (CN) 4 (tib)] n ( 2 ), and [Cu 2 (CN) 2 (tib)] n ( 3 ), have been prepared and characterized by elemental analysis, IR, PXRD, thermogravimetry and single-crystal X-ray diffraction analysis. Complex 1 displays a 3D metal-organic framework with nanosized pores. Complex 2 is a 3D coordination polymer assembled by three μ 2 -cyanides and a μ 3 -cyanide with a very short Cu(I)···Cu(I) metal bond(2.5206 Å). Complex 3 is a 2D coordination polymer constructing from 1D Cu(I)-cyanide zigzag chain and bidentate tib spacer. Three Cu(I) complexes are thermally stable up to 250–350 °C. Complexes 1 – 3 show similar orange emission band at 602 nm originating from LMCT mechanism. [ABSTRACT FROM AUTHOR]

Abstract: Hydrothermal reaction of CuCN with 2,5-bis(3-pyridyl)-1,3,4-oxadiazole (3-bpo) affords a wave-like infinite chain coordination polymer [Cu2(CN)2(3-bpo)] n (1). Replacement of 3-bpo by its isomer 2,5-bis(4-pyridyl)-1,3,4-oxadiazole (4-bpo) could yields polymer [Cu(CN)(4-bpo)] n (2). In the complex 1, the bent 3-bpo ligand adopts bidentate chelating mode binds with the Cu(I)-cyanide chain to form 16-membered macrocyclic structure. The complex 2 exhibits a layered metal–organic framework, in which exo-bidentate 4-bpo ligand connects the Cu(I)-cyanide chains to form 2-D rectangle grid. Both of these Cu(I) complexes are thermal stable under 200°C and release 3-bpo or 4-bpo ligand in 200–360°C. Luminescent study reveals that 1 has green-light emission, while 2 has blue-light emission. [Copyright &y& Elsevier]

Two new Cd(II) coordination polymers based on a flexible ligand 5-(bis(4- carboxybenzyl)amino)isophthalic acid (H 4 L) namely {[Cd 2 (L)(NMP) 2 (H 2 O) 2 ]·H 2 O} n (1) and{[Cd 4 (L) 2 (NMP) 2 (H 2 O)]∙2NMP} n (2) (NMP=N-methyl-2-pyrrolidone) have been prepared under hydrothermal conditions. Structural analyses revealed that 1 and 2 all exhibit three-dimensional network structures. Compound 1 shows 4-connect crb topology with [Cd 2 (CO 2) 4 ] as secondary building unit, while compound 2 can be regarded as a new 4,4,8-connect with a {411.615.82}{45.6}{46} topology with tetranuclear [Cd 4 (CO 2) 8 ]. By step-wise synthesis, tetranuclear cluster-based {[Cd 4 (L) 2 (NMP) 2 (H 2 O)]∙2NMP} n (2) can be synthesized successfully by using compound 1. The powder X-ray diffraction, the thermal stabilities, and solid-state luminescence properties of compounds 1 – 2 have also been investigated. Two 3D Cd coordination polymers with different topology were synthesized successfully. By step-wise synthesis, binuclear-cluster units can be transferred to tetranuclear cluster. Image 1 • Achieving the structure transformation from binuclear units to tetranuclear units by employing a step-wise synthesis method. • Two cadmium coordination polymers have been synthesized by using flexibly carboxylic ligand. • A new topology with 4,4,8-connected 3-nodal net. [ABSTRACT FROM AUTHOR]