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Two in one: A metal-organic framework obtained from three different inorganic building blocks (tetrameric Zn(4) O, trimeric Zn(3) OH, and monomeric Zn) posseses a nested cage-in-cage and framework-in-framework architecture. 24 Zn(4) O tetramers and eight Zn monomers form a sodalite cage into which a cubic cage made from eight Zn(3) (OH) trimers is nestled. Eight monomeric Zn(2+) centers interconnect these two cages., (Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A new class of zeolite-type porous materials in which 3D frameworks are covalently functionalized with crystallographically ordered pendant metal clusters have been synthesized. This work demonstrates a new paradigm for and the feasibility of functionalizing zeolite-type frameworks through the conversion of extraframework sites in mineral zeolites into part of the framework for occupation by dangling metal clusters in metal-organic frameworks., (© 2012 American Chemical Society)

Zeolite A (LTA) is of much interest in zeolite family because of its large-scale industrial applications. Making Zeolite A (a typical 4-connected tetrahedral framework material) with a lower connectivity (3-connected) might lead to new open architecture with expanded ring size and enhanced functionality. The first interrupted Zeolite A with 3-connected network has been experimentally realized here by a boron imidazolate (im) framework material (BIF-20) with 3-coordinate BH(mim)(3)(-) building units. Additionally, a new strategy toward the construction of functional microporous metal-organic frameworks with interrupted zeolite-type topologies is presented by both 3-connected boron imidazolate frameworks (BIF-20 and BIF-21). BIF-20 has an unusual tetrahedral framework with both debonded α and β cages, and exhibits high H(2) uptake capacity., (© 2011 American Chemical Society)

B-hive? A family of crystalline materials analogous to porous AlPO(4) but based on boron imidazolate frameworks (BIFs) can be formed by the crosslinking of various presynthesized boron imidazolates with monovalent cations (Li(+) and Cu(+), see picture). This synthetic method is capable of generating a large variety of open frameworks, ranging from the four-connected zeolitic sodalite type to the three-connected chiral (10,3)-a type.

An ideal adsorbent for separation requires optimizing both storage capacity and selectivity, but maximizing both or achieving a desired balance remain challenging. Herein, a de‐linker strategy is proposed to address this issue for metal–organic frameworks (MOFs). Broadly speaking, the de‐linker idea targets a class of materials that may be viewed as being intermediate between zeolites and MOFs. Its feasibility is shown here by a series of ultra‐microporous MOFs (SNNU‐98‐M, M=Mn, Co, Ni, Zn). SNNU‐98 exhibit high volumetric C2H2 uptake capacity under low and ambient pressures (175.3 cm3 cm−3 @ 0.1 bar, 222.9 cm3 cm−3 @ 1 bar, 298 K), as well as extraordinary selectivity (2405.7 for C2H2/C2H4, 22.7 for C2H2/CO2). Remarkably, SNNU‐98‐Mn can efficiently separate C2H2 from C2H2/CO2 and C2H2/C2H4 mixtures with a benchmark C2H2/C2H4 (1/99) breakthrough time of 2325 min g−1, and produce 99.9999 % C2H4 with a productivity up to 64.6 mmol g−1, surpassing values of reported MOF adsorbents. [ABSTRACT FROM AUTHOR]

Zeolitic imidazolate frameworks (ZIFs) are traditionally synthesized solvothermally by using cost‐ and waste‐incurring organic solvents. Here, a direct synthesis method is reported for ZIF‐8, ZIF‐67, and their heterometallic versions from solid precursors only. This solvent‐free crystallization method not only completely avoids organic solvents, but also provides an effective path for the synthesis of homogeneous mixed‐metal ZIFs. Furthermore, under templating by NaCl/ZnCl2 eutectic salt, carbonization of the ZIF materials gives rise to a series of N‐containing high‐surface‐area carbon materials with impressive catalytic properties for the oxygen reduction reaction. [ABSTRACT FROM AUTHOR]

While many metal oxalate salts are known, few are known to form zeolite‐type topologies. The construction of zeolite types, especially those with low framework density such as RHO, from linear ligands is generally perceived as less likely, because the 180° metal‐ligand‐metal geometry deviates too much from the established strategy of using ligands with bent coordination geometry (centered around 145°) to mimic the geometry in natural zeolites. We show the general feasibility of using linear ligands for the synthesis of zeolite types by reporting a family of indium oxalate salts with multiple zeolite topologies, including RHO, GIS, and ABW. Of particular interest is the synthesis of a zeolite RHO net with double 8‐rings and large alpha cages, which are highly desirable zeolite features. Lay it on the straight line: The general feasibility of using linear ligands for the synthesis of zeolite types is demonstrated by the construction of a family of indium oxalate salts with multiple zeolite topologies, including RHO, GIS, and ABW. Of particular interest is the synthesis of a zeolite RHO net with double 8‐rings and large alpha cages, which are highly desirable zeolite features. [ABSTRACT FROM AUTHOR]

Inter-ligand van der Waals forces play a key role in the synthesis of different ZIF types. Here we report an unusual case involving covalent inter-ligand interactions through disulfide bond formation in a ZIF-8 analogue. It exhibits high CO2 uptake and stepwise adsorption of light hydrocarbons with potential applications in ethane/ethylene separation. [ABSTRACT FROM AUTHOR]

In many areas of chemistry the synthesis of chiral compounds is a target of increasing importance. They play a vital role in biological function and in many areas of society and science, including biology, medicine, biotechnology, chemistry and agriculture. Many pharmaceutical molecules, like their biological targets, are chiral and it is therefore easy to understand the growing demand for efficient methods of producing enantiomerically pure compounds. This is equally true for the preparation of chiral solids, which have potential applications in asymmetric catalysis, chiral separations and the like. In this Review we will consider recent progress and future potential in the development of methods for the preparation of chirally pure solids, in particular where the building blocks of the structure are achiral themselves. We will discuss strategies for the synthesis of both inorganic (for example, zeolites) and inorganic–organic hybrid (for example, metal organic framework) chiral porous solids. [ABSTRACT FROM AUTHOR]

Natural porous solids such as zeolites are invariably formed with inorganic cations such as Na+ and K+ (refs 1, 2). However, current research on new porous materials is mainly focused on the use of organic species as either structure-directing or structure-building units; purely inorganic systems have received relatively little attention in exploratory synthetic work. Here we report the synthesis of a series of three-dimensional sulphides and selenides containing highly mobile alkali metal cations as charge-balancing extra-framework cations. Such crystalline inorganic chalcogenides integrate zeolite-like architecture with high anionic framework polarizability and high concentrations of mobile cations. Such structural features are particularly desirable for the development of fast-ion conductors. These materials demonstrate high ionic conductivity (up to 1.8 × 10-2?ohm-1?cm-1) at room temperature and moderate to high humidity. This synthetic methodology, together with novel structural, physical and chemical properties, may lead to the development of new microporous and open-framework materials with potential applications in areas such as batteries, fuel cells, electrochemical sensors and photocatalysis. [ABSTRACT FROM AUTHOR]

Elaborates a study which reported a novel class of germanate zeolite structures prepared with inorganic cations or organic amines as structure-directing agents. Materials and methods of the study; Evaluation of germanium and gallium ratio; Discussion of structural correspondence between classes of body-centered cubic zeolite-type structures.

Reports on a family of zeolite-type materials that possess two independent sets of three-dimensional cross-linked helical pores, separated by a gyroid periodic minimal surface. Stimulation of research into the preparation of heterogeneous chiral catalysts of separation media that combine both shape selectivity and enantinoselectivity, by the increasing demand for enantimerically pure chemicals; Findings.

Presents the results of research which determined that concentrations of transition-metal atoms in frameworks can be controlled by varying the charge and geometry of the structure-directing amine molecules. Use of zeolite analogs; Generalized synthesis method for generating transition-metal-rich zeolite-type structures; Use of method; Overview of synthesis and products; New analogs and structures; Data.

Reported here is a lithium cubane based zeolitic framework possessing a multi-dimensional channel system. The unique design strategy of adopting the ditopic ligand 4-pyridinol leads to a rigid porous framework with high thermal stability. It has a BET surface area of 440.3 m2g−1and a H2uptake capacity of 108.7 cm3g−1at 77 K. [ABSTRACT FROM AUTHOR]