Syntheses, structures and luminescent properties of seven metal–organic frameworks constructed with a rigid bis(imidazole) ligand and versatile carboxylate acids†
Abstract
Seven new metal–organic frameworks, namely, [Zn5(μ3-OH)2(bdc)2(bimf)2]·4H2O (1), [Zn(bdc)(bimf)]·2H2O (2), [Cd(bdc)(bimf)(H2O)]·2H2O (3), [Cd4(cdc)4(bimf)2(H2O)2]·2H2O (4), [Cd(cdc)(bimf)] (5), [Zn2(Hbtc)2(bimf)2]·H2O (6) and [Cd3(btc)2(bimf)3(H2O)]·2H2O (7) have been synthesized and structurally characterized (H2bdc = 1,4-benzenedicarboxylic acid, H2cdc = 1,4-cyclohexanedicarboxylic acid, H3btc = 1,3,5-benzenetricarboxylic acid and bimf = 9,9-dimethyl-2,7-bisimidazolylfluorene). Compound 1 displays a uninodal 12-connected fcu-framework based on pentanuclear zinc clusters. Compound 2 exhibits a 4-fold interpenetrating framework of SrAl2-topology. Compound 3 presents a 2-fold interpenetration of (4,4) net. Compound 4 shows a uninodal 8-connected framework of hex-topology. Compound 5 features a binodal framework of PtS-topology. Complex 6 features a binodal framework with an unusual (66)·(64·82) topology. Complex 7 defines a pentanodal framework containing 3, 4 and 8-connecting nodes. Their photochemical properties were measured.