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CdSe/ZnS core‐shell quantum dots (QDs) have been immobilized onto solid substrates by matrix assisted pulsed laser evaporation (MAPLE). An UV KrF* (λ= 248 nm, τFWHM≅ 25 ns) excimer laser source was used for irradiations of the composite MAPLE targets. The targets were prepared by the dispersion of the CdSe/ZnS QDs in a solvent with high absorption at the incident laser radiation. The dependence of the surface morphology, crystalline structure, chemical composition, and functional properties of the laser transferred CdSe/ZnS QDs on the processing conditions as incident laser fluence value and ambient atmosphere inside the irradiation chamber was investigated. The possible physical mechanisms implied in the laser ablation process were identified.

CdSe/ZnS core–shell quantum dots (QDs) have been immobilized by ultraviolet matrix-assisted pulsed laser evaporation (UV-MAPLE) onto SiO2glass substrates covered by silica thin films. The silica thin films were deposited by the sol–gel method. An UV KrF* (λ = 248 nm, τfwhm≅ 25 ns) excimer laser source was used for the laser immobilization experiments. Toluene was chosen as solvent material for the preparation of the composite MAPLE targets. The surface morphology and growth mode of the deposited structures were investigated by optical and atomic force microscopy in acoustic (dynamic) configuration. The crystalline structure and chemical composition of the base material used for the preparation of the MAPLE targets as well as the laser transferred QDs were studied by transmission electron microscopy and energy dispersive X-ray spectroscopy. The functional properties of the immobilized QDs were studied by fluorescence microscopy. The immobilized materials form self-organized 2D arrays constituted by complex CdSe/ZnS core–shell QDs preserving the functional properties of the base material used for the preparation of the MAPLE targets.

Free radicals generated by the decarboxylation of dimethoxydioxanecarboxylic acids derived from l-(+)-tartaric acid and l-glyceric acid added to some maleimides and acrylates with high stereoselectivity. This method provides easy access to some chiral building blocks.

We studied the performance of Fusarium solani pisi cutinase, immobilized on a zeolite, in supercritical fluids. The catalytic activity of the enzyme was strongly dependent on water activity, was unaffected by pressure up to 300 bar, and was higher in supercritical ethylene than in supercritical carbon dioxide. The enzyme was very selective toward one of the isomers of 1-phenylethanol, with an enantiomeric excess of virtually 100%, regardless of water activity, pressure, solvent, and temperature. We used the X-ray crystal structure of the enzyme and did a computer modeling of the structures of the transition states formed by the two enantiomers. The differences between these structures helped elucidate the preference for the (R)-enantiomer.

The directing ability of an aziridine group for the epoxidation of adjacent double bonds is demonstrated. The aziridine group is also used to effectively protect a double bond in a cycloenone system for a short synthesis of the title compound.

A general enantioselective synthesis of the paraconic acids was developed. The key step was a highly stereoselective aldol reaction between a dioxane dithioester derived from l-tartaric acid and a suitable aldehyde.

Addition of HOBr (generated in situ) to the diazabicycloheptenone (I) gives the bromohydrin (III) which is partially converted into a mixture of the compounds (IV) and (V), but all attempts to isolate (V) are without avail.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

The title reagent oxidizes the silyl ethers (I), (III) and (Vb) to the carbonyl compounds (II), (IV) and (VI)‐(VIIIa), respectively.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Thermolysis of the sulfinylazetidinones (I) or (IV) yields the title compounds (II) or (V).

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.