Trapped in a “tea bag” : Membrane bags, fabricated from a dialysis membrane, have been employed as semipermeable containers for dendrimer‐immobilised oxazoline–copper(II) Lewis acid catalysts. Dipping them into reactant solutions leads to the catalytic conversion of the substrates, which penetrate the membrane as does the product in the reverse direction (see scheme).
Like pearls on a string , molecular building blocks have been preorganized and then interlinked on a surface (see STM images). In this way both the supramolecular self‐assembly of the reactants as well as the subsequent thermal activation to release the protecting group are controlled.
Up to four adjacent stereocenters can be formed stereoselectively in the construction of a pyrrolizidine unit through a novel organocatalytic reaction that involves treatment of various dienones with ethyl isocyanoacetate (see scheme; DBU=1,8‐diazabicyclo[5.4.0]undec‐7‐ene). Mechanisms for this atom‐economic, one‐pot synthesis have been proposed.
Molecular semiconductors in the guise of three diazine‐functionalized oligothiophenes have been synthesized and their structural, optical, vibrational, electrochemical, and semiconductor properties studied. In their Full Paper on page 5023 ff. , J. T. López Navarrete, A. Facchetti, T. J. Marks et al. describe how these diazine‐functionalized oligothiophenes are reasonably efficient hole transporters.
2009: A boraanthracene odyssey : General routes to boraanthracene derivatives—long proposed, but never observed—are disclosed, along with the structural and photophysical properties of these compounds and their remarkable reactivity towards oxygen.
A facile, self‐seeded , solution–liquid–solid growth of soluble InP and GaP nanowires with a very low amount of native point defects with respect to the carrier concentrations have been synthesized (see scheme) and characterized. They are potentially promising building blocks in optoelectronic applications.
Why bigger is better : A “steric wall” created by the N‐(2,6‐diisopropylphenyl) substituent on the bulky NHC ligand IPr (1,3‐bis(2,6‐diisopropylphenyl)imidazol‐2‐ylidene) guides the reactants to and from the Pd center through weak, fleeting (IPr)H–Pd interactions that help the oxidative addition intermediate escape “the anti‐trap”. The alternative “side” approach leads to transmetalation (the rate‐limiting step) for which a novel Pd–Zn interaction was identified.
Insensitive energetic salts : A series of furazan‐functionalized tetrazolate‐based energetic salts (see figure) were synthesized and characterized. All of the salts exhibit excellent thermal stabilities and high positive heats of formation.
Selective DNA detection: The fluorescence, from stable cationic QDs, is quenched by 90% on complexation with modified DNA molecules. The QD–DNA probe is capable of detecting pathogenic DNA fragments at concentrations as low as 200 nM in solution and shows selective fluorescence recovery in the presence of target DNA (see spectrum c in figure) vs noncomplementary DNA (spectrum d).
Self‐assembly line : In the presence of a DNA analyte or low‐molecular‐weight substrates, multicomponent nucleic acids self‐assemble into cooperatively stabilized functional nanostructures (see scheme) that activate DNAzyme cascades.
Easy come, easy go: Hydroquinone forms a channel structure of cages with hydrogen‐bonded hexagons. These may provide an ideal route for the fast inclusion and facile release of hydrogen molecules (see figure), which can lead to reversible hydrogen storage under mild conditions.
