Zip it up : Attachment of porphyrins onto complementary DNA strands leads to zipper‐porphyrin arrays and, in the presence of eleven modifications, an increase in the melting temperature of the duplex. Mixed zinc and free‐base porphyrin arrays undergo energy transfer from the zinc porphyrin to the free‐base porphyrin in the annealed duplex but not in the denatured form (see scheme), giving access to reversible formation of potential photonic wires.
Out with a bang! Microcapsules have been prepared which, as a result of an explosion triggered by an external stimulus, distribute nanoparticles throughout the local environment both efficiently and rapidly (see picture). In this way a principle found in nature for the dispersal of seeds and defensive materials has now been realized in nanotechnology and might be utilized, for example, for the better distribution of drugs in organs.
Large, larger, …? Replacement of 1,4‐benzenedicarboxylate by 2,6‐naphthalenedicarboxylate in the MIL‐101 structure leads to an isoreticular mesoporous framework containing cages with diameters of 39 and 46 Å. High‐throughput methods are employed to determine appropriate reaction conditions. The microcrystalline compound is characterized by molecular simulation techniques, powder X‐ray diffraction, N2‐sorption, and TEM investigations.
π–π assisted : Photoinduced electron transfer from cofacial porphyrin dimers to electron acceptors is prominently accelerated, whereas the back electron transfer is decelerated, relative to the corresponding porphyrin monomer (see figure).
Organolithium chemistry! An overview of the structure formation principles and the strong structure–reactivity relationship of lithium organics is given. By means of the commonly used lithium bases the deaggregation of the oligomeric parent structures to small adducts is presented (see examples) and compared to the related chemistry of lithiosilanes.
With a sting in its tail : An enantiopure neodymium complex (see scheme) acts as an efficient single‐site initiator for the controlled ring‐opening polymerization of rac‐lactide, forming isotactic polyester. The heteroscorpionate complex was characterized spectroscopically and by X‐ray diffraction.
A promising method for the production of germanium photonic crystals consists of electrodeposition of Ge from GeCl4‐containing ionic liquids inside templates of polystyrene colloidal crystals and subsequent removal of the template. This room‐temperature method gives rise to the fabrication of a three‐dimensional highly ordered macroporous germanium nanostructure (see picture; scale: 2 μm) as a prototype of a photonic crystal.
Surfing gold and silica! A new cholesterol‐based tether was attached to both amine‐functionalised silica and gold surfaces. The resultant self‐assembled monolayers, which can be deep‐UV‐patterned, were used in attaching essentially equivalent patterned supported lipid bilayers both on silica for fluorescence studies (left figure) and on gold for impedance studies (right figure).
Involuntary association : Anionic β‐galactosidase enzymes associate with positively charged Au nanoparticles to produce reduced‐charge conjugates, which assemble at oil–water interfaces to result in stable microcapsules (see picture). The microcapsules were formed quickly and showed high enzymatic activity, which makes them promising materials for biotechnology applications.
Two birds with one auric stone : The title system acts as a highly efficient heterogeneous catalyst for the one‐pot tandem synthesis of imines or oximes from alcohols and the corresponding amines under mild conditions (see scheme; HAP= hydroxyapatite).
Spontaneous formation of smectic and columnar structures was observed when spherical gold nanoparticles were functionalized with mesogenic thiols (see layered structure and X‐ray pattern of a sample in smectic phase). The particle ordering is stimulated by softening of the interparticle potential and flexibility for deformation of the grafting layer.
Confined, but happy : The triflate salt of a germanium(II) dication, an atomic cation of a nonmetal, was isolated by encapsulation in [2.2.2]cryptand (see formula and molecular structure in the crystal). The cryptand satisfies the electron demand of the cation and sterically protects it (see space‐filling depiction, right).
Novel thin‐film materials have been produced from indolo[3,2,1‐jk]carbazole (see picture). These are conducting and redox‐active and, unusually, consist of three distinct covalently coupled luminescent dimer species, consistent with a specific radical‐cation coupling mechanism.
In a glass house : Silica‐encapsulated self‐assembled monolayers (SAMs) on tunable gold/silver nanoshells were used as labels for surface‐enhanced Raman scattering (SERS). This concept combines the spectroscopic advantages arising from maximum surface coverage and uniform molecular orientation of the Raman reporter molecules within the complete monolayer together with the high chemical and mechanical stability of the glass shell.
Osmabenzenes can be easily synthesized from two η2‐coordinated olefin osmacycles in the presence of benzonitrile by means of facile hydrogen‐transfer conversions (see graphic). Mechanisms for the formation of osmabenzenes are proposed based on DFT calculations.
