A new microporous metal-organic framework compound featuring chiral (salen)Mn struts is highly effective as an asymmetric catalyst for olefin epoxidation, yielding enantiomeric excesses that rival those of the free molecular analogue. Framework confinement of the manganese salen entity enhances catalyst stability, imparts substrate size selectivity, and permits catalyst separation and reuse.

An extended network, {[Dy4(OH)4(asp)3(H2O)8](ClO4)2⋅10 H2O}n, having three‐dimensional channels with a spacing of 11.78 Å (see picture) has been prepared by mixing Dy(ClO4)3 and L‐aspartic acid in aqueous solution, and subsequently adjusting the pH values to about 6.5 using aqueous NaOH solution. This open‐framework compound is representative for the assembly of discrete lanthanide cubanes into supercubanes.

Rings of 24 atoms form part of the two‐dimensional structure of the novel compounds [NdM(bpym)(H2O)4(CN)6]⋅3 H2O (M = Fe (1), Co (2); bpym = 2,2′‐bipyrimidine). These compounds are the first two‐dimensional cyano‐bridged species containing lanthanide and transition metal centers (see picture). The structures and magnetic properties are investigated.

A novel water tape consisting of fused cyclic water pentamers has been observed in a supramolecular compound.

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Enantioselective syntheses O 0031A Metal-Organic Framework Material that Functions as an Enantioselective Catalyst for Olefin Epoxidation. -A novel, microporous metal-organic framework compound containing chiral Mn(salen) struts appears to be an efficient and reusable asymmetric catalyst for the olefin epoxidation. In comparison to the free Jacobsen-type catalyst, framework immobilization confers multiple advantages such as higher stability, easier separation, recyclability, and substrate size selectivity. -(CHO, S.-H.; MA, B.; NGUYEN, S. T.; HUPP*, J. T.; ALBRECHT-SCHMITT, T. E.; Chem.

In 2006, 128 serum samples were collected from three populations in Tianjin, China: office cleaners, university students, and policemen. These samples were all analyzed for polybrominated diphenyl ethers (PBDEs) and for other brominated flame retardants (BFRs). The median concentration of total PBDEs (sum of 41 congeners) was 7.1 ng/g lipid, ranging from 0.48 to 1980 ng/g lipid. Among these PBDE congeners, the median sum of the tri- to hepta-PBDE (SigmaPBDE3-7) congener concentrations was 2.9 ng/g lipid, ranging from 0.48 to 20 ng/g lipid. The most common tri- to heptabrominated congeners were BDE-47 (30% of total), BDE-99 (24%), BDE-183 (15%), BDE-153 (12%), BDE-28 (9.5%), and BDE-100 (6.2%). These levels of SigmaPBDE3-7 were similar to those observed in Europe and Asia but were much lower than those observed in North America. Highly brominated BDE congeners were detected in some serum samples. In particular, BDE-209 was detected in 28 samples; the median BDE-209 concentration in these samples was 42 ng/g lipid, ranging from ND to 1770 ng/g lipid. The total PBDE levels in office cleaners were significantly higher than in university students and policemen. In addition, we also measured several other BFRs. Hexabromobenzene (HBB) was identified in 26 samples with a median concentration of 0.27 ng/g lipid, ranging from 0.11 to 1.50 ng/g lipid. Pentabromoethylbenzene (PBEB), hexabromocyclododecane (HBCD), 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE), and decabromodiphenylethane (DBDPE) were not detected in any of these samples.