Необходимость общих подходов в применении мер уголовной ответственности за компьютерные преступления в Республике Беларусь, Российской Федерации и Украине

Материалы III междунар. науч. конф., 22-23 мая 2003 г

Hydroquinone–pyrrole dyads with varied linkers

A series of pyrroles functionalized in the 3-position with p-dimethoxybenzene via various linkers (CH2, CH2CH2, CH=CH, C≡C) has been synthesized. Their electronic properties have been deduced from 1H NMR, 13C NMR, and UV–vis spectra to detect possible interactions between the two aromatic subunits. The extent of conjugation between the subunits is largely controlled by the nature of the linker, with the largest conjugation found with the trans-ethene linker and the weakest with the aliphatic linkers. DFT calculations revealed substantial changes in the HOMO–LUMO gap that correlated with the extent of conjugation found experimentally. The results of this work are expected to open up for use of the investigated compounds as components of redox-active materials in sustainable, organic electrical energy storage devices

Investigation of the Redox Chemistry of Isoindole-4,7-diones

Quinone derivatives have been proposed as active components in lithium ion battery (LIB) electrode materials. In this work the electrochemistry of a series of substituted isoindole-4,7-diones (IIDs) was investigated. Three new IID derivatives were synthesized and characterized by various electrochemical and spectroscopic techniques. Polymerization was attempted to achieve a conducting polymer with redox active quinone side groups, which would be advantageous in a LIB application. A combination of <i>in situ</i> spectroelectrochemical measurements and density functional theory (DFT) calculations was used to investigate the proton coupled redox reactions of the IIDs. Results from a previous computational study of the IIDs were compared with experimental data here, and the agreement was very good. The energy of the spectroscopic transitions in the UV and in the visible region showed different correlation with redox potential and quinone substituent in the series of IIDs. This behavior was rationalized by examination of the involved molecular orbitals. The results indicated that the properties of the quinone unit, such as the redox potential, could be selectively varied by substitution

Formation of persistent organic diradicals from N,N′-diphenyl-3,7-diazacyclooctanes

N,N′-Diphenyl-3,7-diazacyclooctane and structurally related N,N′-diphenylbispidine derivatives react with silver(I) ions in a high-yielding C–C coupling reaction to produce dication–diradical species, with the silver ions serving a double function both as template and as an oxidant. The resulting bis(benzidino)phane derivatives are persistent organic radicals, stable for several months in solution as well as in the solid state, at room temperature and above, as well as being exposed to the atmosphere. The molecular structure features a double-decker cyclophane motif, stabilized by intramolecular π-dimerization of two delocalized benzidinium radical segments. Intermolecular π-dimers are formed in the solid state. Graphical abstract: [Figure not available: see fulltext.]

Probing Polymer–Pendant Interactions in the Conducting Redox Polymer Poly(pyrrol-3-ylhydroquinone)

Conducting polymers with redox active pendant groups show properties typical of both conducting polymers (i.e., capacitive charging and intrinsic conductivity) and redox polymers (i.e., electrochemical surface response at the formal potential of the pendant groups). The two components can also exert significant interaction on each other during their separate electrochemical reactions. In poly­(pyrrol-3-ylhydroquinone), a polypyrrole derivative functionalized with hydroquinone units, the redox conversion of the pendant groups has a large impact on the polymer backbone. This interaction is manifested by a loss of bipolaron states during the hydroquinone oxidation, leading to a decreasing p-doping level with increasing potential, something which, to the best of our knowledge, has never been observed for a conducting polymer. Another effect is a contraction of the polymer film, and subsequent mass loss due to solvent expulsion upon hydroquinone oxidation, which counteracts the normal swelling of polypyrrole with increased potential. The conducting redox polymer under investigation has been synthesized via two routes, leading to different fractions of subunits bearing redox active hydroquinone groups. While the redox potentials are unaffected by the synthesis route, the backbone/pendant group interaction varies notably depending on the degree of quinone functionalization. This type of polymers could find use in, e.g., organic energy storage materials, since the polymer backbone both increases the electronic conductivity and prevents dissolution of the active material, as well as in actuator application, due to polymer contraction over the relatively narrow potential region where the pendant group redox chemistry occurs