An unprecedented (3,4)-connected self-penetrating network of zinc complex: In situ formation of a tetradentate N-heterocyclic ligand under POMs-mediated hydrothermal conditions

The reaction of lacunary polyanion [α-H2P2W12O48]12−, zinc acetate, bpp (1,3-bis(4-pyridyl)propane) and BTC (1,3,5-benzenetricarboxylate) in an acidic aqueous solution led to the isolation of a new complex [Zn3(BTC)2(chtpy)(H2O)2] · 2H2O (1), which crystallizes in the space group C2/c with a = 28.988(6) Å, b = 11.254(2) Å, c = 17.347(4) Å, V = 4682.5(2) Å3, Z = 4. X-ray diffraction analysis reveals that there exists the generation of in situ ligand through simultaneous dehydrogenative coupling and hydroxylation of an N-heterocyclic ligand in complex 1. More interestingly, it exhibits an unprecedented (3,4)-connected (82.10)2(83)2(84.10.12)(85.10) topology which has been reported for the first time and shows self-penetrating nature at the same time.

Graphical abstractA new complex [Zn3(BTC)2(chtpy)(H2O)2] · 2H2O (1) has been synthesized, exhibiting an unprecedented (3,4)-connected (82.10)2(83)2(84.10.12)(85.10) topology which has been reported for the first time. Furthermore, the resulting 3D metal-organic framework also shows self-penetrating nature. More interesting, this is the first time that simultaneous dehydrogenative coupling and hydroxylation of an N-heterocyclic ligand has been observed in the resulting complex with mixed ligands.Figure optionsDownload full-size imageDownload as PowerPoint slide