N. F. Goldshleger

Magnesium Octa(benzo-15-crown-5)phthalocyaninate in the Sodium Dodecyl Sulfate Solutions: A Study Using Electron and 1 H NMR Spectroscopy

The behavior of magnesium octa(benzo-15-crown-5)phthalocyaninate in water medium in the presence of sodium dodecyl sulfate was studied using both electronic and 1H NMR spectroscopy, including the method of two-dimensional 1H-1H correlation NOESY. In the microheterogeneous environment of the CH3(CH2)11OSO3Na solutions at the concentrations of the latter close to the CMC the phthalocyanine is in monomeric form, while at the concentration less than the critical micelle-formation concentration it becomes a dimer or even more aggregated. The results of the NMR spectroscopic investigation indicate that magnesium octa(benzo-15-crown-5)phthalocyaninate preferrably binds to the CH3(CH2)11OSO3Na micelle in the hydrophobic region of the latter.

Selective rhodium-containing zeolite catalysts for cyclodimerization of bicyclo[2.2.1]hepta-2,5-diene

Abstract It has been shown that norbornadiene (NBD) is dimerized in the presence of rhodium zeolite systems forming hexacyclodimers, exo-endo- and endo-endo -hexacyclo[9.2.1.0 4.6 .0 3.8 .0 2.10 .0 5.9 ]tetradec-12-enes preferentially. The effect of the structure, preparation procedure and pretreatment of the catalysts on their activity and selectivity in norbornadiene cyclodimerization and the change in the rhodium electronic state in the course of the reaction have been studied. Alcohols (nortricyclan-3-ol and norbornen-5-ol) and ethers (3-tricyclo[2.2.1.0 2.6 ]-heptyloxy-3′)bicyclo[2.2.1]hept-5-ene and 3,3′-oxydinortricyclane) as well as norbornadiene cyclodimers were formed when the catalysts containing both the rhodium and acid sites were pretreated with retaining adsorbed water. Interaction of the Rh Na-ZSM-5 catalyst with H 2 or norbornadiene under mild conditions (130–150°C) leads to the stabilization of a significant portion of rhodium in the form of Rh(I), and apparently a complex formed is like that of [NBD-Rh(I)]-O zeol . Norbornadiene cyclodimerization takes place with the participation of the active centres localized on the outside surface of the zeolite crystals.

Platinum Fulleride Reduction by Molecular Deuterium or 9, 10-dihydroanthracene

Abstract C60Pt reacts with D2 (1-2 MPa D2 pressure and 373-723 K) to form C60Dx (x = 2-26) and Pt clusters. C60 in platinum fulleride is also reduced by dihydroanthracene to hydrofullerenes. The value of EbPt4f7/2 (72.4 eV) obtained for platinum in the starting C60Pt suggests partial charge transfer from the Pt atom to C60 in C60Pt.

Solubilization of Crown-Substituted Magnesium Phthalocyaninates in Solutions of Salts of Bile Acids

Crown-containing Pc Mg[(B15C5O)8Pc], Mg[(B15C5O)4Pc], and Mg[(15C5)4Pc] are in the monomolecular state in solutions of synthetic anionic surfactants: sodium dodecylsulfate and sodium dodecylbenzenesulfonate. In micellar solutions of bile-acid salts, molecular organization of crown-substituted Pc with different methods of introduction of crown groups into the macrocycle and their different numbers changes their state from predominantly monomeric for Mg[(B15C5O)8Pc] in the presence of NaCl to the aggregated one in the case of Mg[(15C5)4Pc)]. Magnesium phthalocyaninate with annulated (15-crown-5)-fragments, Mg[(15C5)4Pc], is characterized by the highest sensitivity to the structure of the micelle-forming biocompatible surfactant.

Monomerization of crown-containing phthalocyanines in microheterogeneous organized systems

Optical spectroscopy in the UV and visible ranges, dynamic light scattering, and 1H NMR spectroscopy are used to study monomerization of magnesium octa[(4′-benzo-15-crown-5)oxy]phthalocyaninate (Mgcr8Pc) in aqueous solutions of anionic surfactants: sodium dodecyl benzenesulfonate, sodium bis-(2-ethylhexyl)sulfosuccinate, and sodium deoxycholate (SDBS, AOT, and SDC, accordingly). Structural differences in surfactant molecules determine organization of Mgcr8Pc molecules in microheterogeneous media. It is found that Mgcr8Pc is in a monomeric form in aqueous SDBS solutions at concentrations in the range of CMC1 to CMC2 (critical micelle concentration) and it is in a dimeric and/or aggregate form at concentrations below CMC1. In AOT/water solutions (direct micelles) or hexane/AOT (0.1 M)/water (inverted micelles), Mgcr8Pc is solubilized forming dimeric and/or aggregate forms. In micellar solutions of SDC, the Mgcr8Pc monomer is predominantly formed in the presence of NaCl. The results obtained using the NMR spectroscopy technique agree with the binding of Mgcr8Pc by SDBS micelles similar to solubilization of phthalocyanine by micellar solutions of sodium dodecyl sulfate.

Self-Assembling Ensembles of Silicomolybdic Acid-Diamines

Modification of the surface of the conductive glass [conductive layer is indium-tin oxide (ITO)] by diamines (1,8-diaminooctane and piperazine) and organic polycations [poly(diallyldimethylammonium chloride) and poly(allylamine) hydrochloride] followed by the formation of electroactive composites with silicomolybdic acid H4SiMo12O40 was carried out. The two-layer ITO/cationic/anionic coatings were shown to differ by the shape of cyclic voltammograms depending on the cationic component.