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Five non-interpenetrated microporous coordination polymers (MCPs) are derived by vertex desymmetrization by using linkers with symmetry inequivalent coordinating groups and these MCPs have included properties like rare metal clusters, new network topologies and supramolecular isomerism. The structural features present in MCPs derived from the reduced symmetry linkers have included the presence of more than one type of Cu-paddlewheel in a structure derived from a terphenyl tricarboxylate and a three-bladed zinc paddlewheel metal cluster in an MCP derived from a pentacarboxylated triphenylbenzene linker.

The applications of microporous coordination polymers (MCPs) as an efficient adsorbents for the removal of the organosulfur compounds dibenzothiophene (DBT) and 4,6-dimethyldibenzothiophene (DMDBT) from model diesel fuel and diesel fuel are demonstrated. The realization of high selectivities and capacities, particularly for the adsorption of the refractory compounds that are difficult to eradicate using current desulfurization techniques, in a reversible sorbent indicated that fuel desulfurization might be an important application for MCPs.

The article discusses the liquid phase adsorption exhibited by the microporous coordination polymers (MCPs), which are capable of adsorbing large quantities of the organosulfur compounds. The shape and size of the pore is shown to highly affect the adsorption capacity of a given MCP.

A new Pd-catalyzed oxidation reaction is described for the stereospecific conversion of enynes into cyclopropyl ketones. The analysis has shown that unlike related [Pd.sup.II/0], Au and Pt-catalyzed cyclopropane-forming reactions, these transformations have proceeded with net inversion of geometry with respect to the starting olefin.

Zeolites are widely used in industrial processes, mostly as catalysts or adsorbents. Increasing their micropore volume could further improve their already exceptional catalytic and separation performances. We report a tunable extraction of zeolite framework cations (Si, Al) on a faujasite-type zeolite, the archetype of molecular sieves with cages and the most widely used as a catalyst and sorbent; this results in ca. 10% higher micropore volume with limited impact on its thermal stability. This increased micropore volume results from the opening of some of the small (sodalite) cages, otherwise inaccessible to most molecules. As more active sites become accessible, the catalytic performances for these modified zeolites are substantially improved. The method, based on etching with NH4F, is also applicable to other cage-containing microporous molecular sieves, where some of the most industrially relevant zeolites are found. [ABSTRACT FROM AUTHOR]

Carbon dioxide release into the atmosphere from fossil fuel burning has been identified as the major reason behind global warming. This has triggered immense interest in developing cost-efficient methods and materials for CO2 capture in recent years. In this study, benzimidazole was used as an inexpensive and commercially available single source precursor for carbon and nitrogen to successfully produce heteroatom-doped porous carbons (BIDCs) with remarkable CO2 capture properties. Our synthetic protocol involves solid-state addition of potassium hydroxide to the benzimidazole precursor to prevent its evaporation and subsequent carbonization–activation of the nonvolatile powdery mixture to ensure simultaneous porosity formation and heteroatom doping. The porous structure and heteroatom doping level can be controlled by tuning the KOH/benzimidazole ratio and carbonization temperature. The highest CO2 uptake values at 0.1 bar (1.60 mmol g−1), 1 bar (5.46 mmol g−1), and 30 bar (28.10 mmol g−1) were realized for three different carbons at 298 K. These diverse CO2 capture performances originate from a unique combination of surface chemistry and porous architecture for each BIDC. The carbon materials are regenerable and highly promising for CO2 separation or storage. [ABSTRACT FROM AUTHOR]

The use of colloidal crystals with various primary particlesizesas templates leads to the formation of three-dimensionally orderedmesoporous (3DOm) carbons containing spherical pores with tailorablepore size and extremely high pore volumes. We present a comprehensivestructural characterization of these novel carbons by using nitrogen(77.4 K) and argon (87.3 K) adsorption coupled with the applicationof novel, dedicated quenched solid density functional theory (QSDFT)methods which assume correctly the underlying spherical pore geometryand also the underlying adsorption mechanism. The observed adsorptionisotherms are of Type IV with Type H1-like hysteresis, despite thefact that pore blocking affects the position of the desorption branch.This follows also from detailed, advanced scanning hysteresis experimentswhich not only allow one to identify the underlying mechanisms ofhysteresis, but also provide complementary information about the textureof these unique porous materials. This work addresses the problemof pore size analysis of novel, ordered porous carbons and highlightsthe importance of hysteresis scanning experiments for textural analysisof the pore network. [ABSTRACT FROM AUTHOR]