Recycling of “green” solvents : Recycling of ionic liquids with high efficiency is of key importance on going from the laboratory‐scale to large‐scale industrial application of these solvents.
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).
Bicomponent supramolecular polymers , consisting of two alternating molecules bridged through six H‐bonds, are observed by STM at the solid–liquid interface. Control of the geometry of the 1D architecture was obtained by using two different connecting molecules with different conformational rigidity, affording either linear (see picture, left) or zigzag (right) motifs.
On edge : Self‐assembled monolayers of a bis(hydrazone)‐based molecular grid physisorbed on graphite are studied by scanning tunneling microscopy (see picture). High order is attained at the supramolecular level by thermal annealing of the grid‐based films. A preferential edge‐on configuration of the molecular grid with respect to the substrate is found.
Into the looking glass! Low temperature photoisomerization studies on some arenes have been studied in different organic glasses. The results are consistent with a possible softening of the glass and offer an explanation for the mechanism of photoisomerization in a confined medium.
They all fall down : The value of domino processes can be greatly enhanced when the possibility exists for one to selectively diverge from a common intermediate. In preliminary studies the dual reactivity of aryl–palladium intermediates is exploited. A diverse array of fluorene and phenanthrene derivatives were synthesized in a rapid and efficient manner (see scheme).
Seleno fluorescent probe : An organoselenium fluorescent probe (FSe‐1) for mercury was designed based on the irreversible deselenation mechanism. FSe‐1 exhibits an ultrahigh selectivity and sensitivity for Hg2+ detection only for reactive selenium atom sites, due the strong affinity between Se and Hg. Furthermore, the new probe has been successfully used for imaging mercury ions in RAW 264.7 cells (a mouse macrophage cell line; see figure).
The true ground state of 1 is a matter of debate, but for clarity and convenience the allene resonance form 1 a , is the most appropriate. The arguments for aromaticity made by Christl and Engels are shown to be incorrect.
