A porous metal-organic framework constructed from carboxylate-pyrazolate shared heptanuclear zinc clusters: synthesis, gas adsorption, and guest-dependent luminescent properties.

A three-dimensional porous structure of [Zn7O2(bpdc)4(dmpp)2]·6DEF·10H2O (MAC-7, H2bpdc = 4,4'-biphenyldicarboxylic acid, Hdmpp = 3,5-dimethyl-4-(4'-pyridyl)pyrazole), built of 12-bridged carboxylate-pyrazolate shared Zn7O2 clusters, has been synthesized. Because of the presence of 12-bridged carboxylate-pyrazolate shared building block, MAC-7 is a double-linked pcu-type framework and shows reversible phase transformation. Photoluminescent property studies indicate that MAC-7 could sense nitrobenzene over toluene, p-xylene, and mesitylene by luminescent quenching.