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Three metal–organic frameworks Zn5(μ-OH)(BTC)3(phen)4·5H2O (HUT-11), Ce5(μ-OH)(BTC)3 (phen)4 (HUT-091) and Mn5(μ-OH)(BTC)3(phen)4·5H2O (HUT-101) have been synthesized, based on the ligands of 1,3,5-benzenetricarboxylic acid (H3BTC) and phenanthroline (phen) in the presence of Zn, Ce and Mn metal ions. The flexible ligand of BTC gives the remarkable properties of the microporous coordination polymers, that exhibits infrequent (3,4,5)-connected (4·6·8)2(4·82)(42·62·82)(42·82·102)(4·64·85) topology by using Zn, Ce or Mn metal clusters and H3BTC as nodes. The thermal stability of each compounds relies on the atmosphere and Ce-MOFs stabilize till 600 °C in N2. The photocatalytic properties of Zn-MOFs and Ce-MOFs on reduction of Cr6+ have also been studied and Ce-MOFs are more active and can be recycled at least in three times.

A highly diastereoselective annulation strategy for the synthesis of alicyclic ketones from diols and pentamethylacetophenone is described. This process is mediated by a commercially available iridium(III) catalyst, and provides efficient access to a wide range of cyclopentane and cyclohexane products with high levels of stereoselectivity. The origins of diastereoselectivity in the annulation reaction have been explored by a series of control experiments, which provides an explanation for how each stereocentre around the newly forged ring is controlled.

An aluminosilicogermanate with a DFT zeotype framework (denoted as SU-57) was synthesized for the first time by ethanol-assisted hydrothermal synthesis at 160 and 170 °C. The compound was characterized by single crystal and powder X-ray diffraction, scanning and transmission electron microscopy, energy dispersive spectroscopy (EDS), thermogravimetry (TG) and solid state nuclear magnetic resonance (NMR) spectroscopy. SU-57 crystallizes in space group P42/n with estimated a ≈ 10.38-10.46 Å, c ≈ 8.88-8.91 Å, V ≈ 957-975 Å3. It has variable Al-Si-Ge composition with an approximate formula |C2H10N2| [Al(SixGe1-x)O4]2 (x ≈ 0.3-0.9), which results in a super-structure originated from different cation occupancies of the two unique tetrahedral (T) sites. Single crystal X-ray structure refinements, together with results from X-ray powder diffraction (XRPD) and EDS analysis, showed that (i) the AlO4 and (Si, Ge)O4 tetrahedra are only partially ordered over the DFT framework and do not follow a strict alternating manner. (ii) Al resides predominantly on one T site and Si and Ge predominantly on the other. (iii) The Al cation concentration (Al/(Al + Si + Ge)) is nearly constant and slightly less than 50 at%, while the Si and Ge cation concentrations vary over a large range. (iv) Al and Ge occupy both T sites. The cation disorder was confirmed by 27Al and 29Si solid state NMR. TG analysis and in situ XRPD showed that SU-57 was stable up to 375 °C in N2 atmosphere. © 2008 Elsevier Inc. All rights reserved.