Construction of Zn(II) microporous metal-organic frameworks based on 1,1′-ethynebenzene-3,3′,5,5′-tetracarboxylate

Three novel microporous zinc MOFs, [Zn-3(EBTC)(2)]center dot 2(CH3)(2)NH2 center dot 0.5DMSO.3H(2)O (1), [Zn(EBTC)(0.5)(BPY)]center dot 2DMSO center dot 0.5DMF center dot 2H(2)O (2) and [Zn-2(EBTC)(BPP)(2)]center dot 3DMSO center dot 2DMF center dot 5H(2)O (3) (EBTC = 1,1'-ethynebenzene-3,3',5,5'-tetracarboxylate, BPY = 4,4'-bipyridine, BPP = 1,3-bi(4-pyridyl)propane), have been synthesized under solvothermal conditions. The versatile coordination modes of EBTC are the key to such diverse MOFs. The results of X-ray single diffraction analyses indicate that 3D microporous MOF 1 with fla topology possesses 2D [Zn-3(EBTC)(2)](infinity) layer built from 1D double-chain-like motif containing trinuclear [Zn-3(COO)(8)](2-) SBUs, in which the two phenyls of EBTC are almost perpendicularly arranged. Compound 2 is a 3D layer-pillar structure with Zn(II) ions bridged by planar EBTC to generate 2D [Zn(EBTC)(0.5)](infinity) sheet, and the 2D sheets are further pillared by rigid BPY to form a 3D porous framework with fsc topology. Complex 3 exhibits a 3D 2-fold interpenetrating framework with (4.6(4).8)(2)(4(2).6(4)) topology, in which the flexible BPP links the 1D [Zn-2(EBTC)](infinity) ladder to form a 2D [Zn-2(EBTC)(BPP)(2)](infinity) structure with large 1D channels, which leads the flexible 2D framework to 2-fold interpenetration and forms a 3D porous network. Complexes 1 and 3 exhibit good luminescent properties around the blue-violet region. (C) 2014 Elsevier B.V. All rights reserved.