Ionene supported peroxodisulfates: Polymeric reagents for the oxidative deprotection of TMS and THP ethers and oxidative cleavage of the C=N bond in water

Oxidative deprotection of trimethylsilyl and tetrahydropyranyl ethers, and deprotection of phenylhydrazones, semicarbazones, and oximes to their corresponding carbonyl compounds carried out in water at reflux condition using ionene supported peroxodisulfates is reported. The reagents are recyclable and products are obtained in excellent yield under environmentally benign conditions without overoxidation to carboxylic acid.     

<Emphasis Type="Italic">Raman</Emphasis> Spectroscopy and <Emphasis Type="Italic">Ab-Initio</Emphasis> Model Calculations on Ionic Liquids

Summary. A review of the recent developments in the study and understanding of room temperature ionic liquids are given. An intimate picture of how and why these liquids are not crystals at ambient conditions is attempted, based on evidence from crystallographical results combined with vibrational spectroscopy and ab-initio molecular orbital calculations. A discussion is given, based mainly on some recent FT-Raman spectroscopic results on the model ionic liquid system of 1-butyl-3-methylimidazolium ([C₄ mim][X]) salts. The rotational isomerism of the [C₄ mim]⁺ cation is described: the presence of anti and gauche conformers that has been elucidated in remarkable papers by Hamaguchi et al. Such presence of a conformational equilibrium seems to be a general feature of the room temperature liquids. Then the “localized structure features” that apparently exist in ionic liquids are described. It is hoped that the structural resolving power of Raman spectroscopy will be appreciated by the reader. It is of remarkable use on crystals of known different conformations and on the corresponding liquids, especially in combination with modern quantum mechanics calculations. It is hoped that these interdisciplinary methods will be applied to many more systems in the future. A few examples will be discussed.     

Reaction sites of <Emphasis Type="Italic">N,N′</Emphasis>-substituted <Emphasis Type="Italic">p</Emphasis>-phenylenediamine antioxidants

The geometries of N,N′-diphenylbenzene-1,4-diamine (DPPD), N-phenyl-N′-(1-phenylethyl)benzene-1,4-diamine (SPPD), N-(4-methylpentan-2-yl)-N′-phenylbenzene-1,4-diamine (6PPD), N-propan-2-yl-N′-phenylbenzene-1,4-diamine (IPPD), N-(2-methoxybenzyl)-N′-phenylbenzene-1,4-diamine (MBPPD), and N-phenyl-N′-(2-phenylpropan-2-yl)benzene-1,4-diamine (CPPD) as well as of their dehydrogenation products were optimized by the semiempirical AM1 method. The results support the idea of stable N_B=C_X structures formation during the consecutive dehydrogenation of SPPD, 6PPD, IPPD, and MBPPD antioxidants. The biradicals formed during the second step of dehydrogenation of substituted phenylenediamines might be important for their antioxidant effectiveness. Dedicated to Professor Vladimír Kvasnička, DrSc., in honour of his 65th birthday     

<Emphasis Type="Italic">peri</Emphasis>-Naphthylenediamines: XXXIX. Synthesis and Structure of <Emphasis Type="Italic">N,N′,N′</Emphasis>-Trimethyl-<Emphasis Type="Italic">N</Emphasis>-nitrosonaphthalene-1,8-diamine Derivatives

The corresponding N-nitroso derivatives were synthesized by the action of nitrous acid on N,N,N′-trimethylnaphthalene-1,8-diamine, N,N,N′-trimethyl-5-nitronaphthalene-1,8-diamine, and N,N,N′-trimethylacenaphthene-5,6-diamine, and molecular structure of the products was studied.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 41, No. 7, 2005, pp. 1020–1027.Original Russian Text Copyright © 2005 by Koroleva, Dyablo, Pozharskii, Sennikova, Starikova.     

Structural analysis of <Emphasis Type="Italic">w</Emphasis>/<Emphasis Type="Italic">o</Emphasis>/<Emphasis Type="Italic">w</Emphasis> multiple emulsions by means of DSC

Summary The properties of the inner and the external aqueous phases, were studied in w/o/w multiple emulsions with light microscopic image analysis and differential scanning calorimetry (DSC). The importance of multiple emulsions lies in the presence of these aqueous phases, making them available for sustained, controlled drug delivery systems. Differentiation of these two aqueous phases, studying the effect of manufacturing technology on droplet structure, quantitative determination of phase volumes and any changes occurring during storage are essential when planning w/o/w emulsions. The present study uses microscopic observations combined with DSC measurements in order to identify the formed structure, at developmental stage in case of different components, preparation methods, and stirring rates. These tools are beneficial during manufacturing as in process controls, or to ensure product quality.     

<Emphasis Type="Italic">N,N′</Emphasis>-Bis(triethoxysilylmethyl)thiocarbamide and Poly[<Emphasis Type="Italic">N,N′</Emphasis>-bis(silsesquioxanylmethyl)thiocarbamide <Emphasis Type="Italic">S,S</Emphasis>-dioxide]

Condensation of (aminomethyl)triethoxysilane with thiocarbamide in the presence of catalytic amounts of ammonium sulfate was used to synthesize N,N-bis(triethoxysilylmethyl)thiocarbamide. The latter was brought into oxidative hydrolytic polycondensation with H₂O₂ to obtain poly[N,N′-bis(silsesquioxanylmethyl)thiocarbamide S, S-dioxide] whose properties were compared with the properties of poly[N,N′-bis(silsesquioxanylpropyl)thiocarbamide S,S-dioxide]. Both polymers in highly acidic media rather strongly absorb Ag(I), while at pH 7 they reduce most absorbed Ag⁺ to the metal. Their reaction with potassium permanganate involves reduction of Mn⁷⁺ to Mn⁴⁺. The first polymer is a less effective sorbent and redox agent than the second.__________Translated from Zhurnal Obshchei Khimii, Vol. 75, No. 7, 2005, pp. 1154–1156.Original Russian Text Copyright © 2005 by Voronkov, Vlasova, Grigor’eva, Pozhidaev, Bol’shakova.     

Synthesis of new <Emphasis Type="Italic">N</Emphasis>-aminoglycosides based on halo-substituted <Emphasis Type="Italic">p</Emphasis>-phenylenediamines and <Emphasis Type="Italic">p</Emphasis>-aminophenols

Condensation of the monosaccharides D-glucose and D-galactose with synthesized halo-substituted p-phenylenediamines and 4-amino-2,6-dibromophenol was studied. It was found that glycosylation occurred only at the 4-amino group that was sterically unhindered by the halogen atom. The position of the aglycon in the glycoside was established by PMR spectroscopy.     

Selective hydrogenation of <Emphasis Type="Italic">α</Emphasis>,<Emphasis Type="Italic">β</Emphasis>-unsaturated carbonyl compounds on supported Ru-Sn catalysts

Selective catalytic hydrogenation of unsaturated carbonylic compounds to unsaturated alcohols on bi-metallic Ru-Sn catalysts/support was studied. The catalysts were prepared by the sol–gel method and the method of co-impregnation with the objective to evaluate selected parameters of preparation, i.e., the amount of modifying tin and the support (TiO₂, SiO₂, Al₂O₃), on their catalytic activity and selectivity. A significant modifying effect of tin was proved, especially its positive effect on the selectivity. Concerning the selectivity as well as the activity, Al₂O₃ was found to be the optimal support. Furthermore, the effect of a substrate was studied with results proving suitability of this catalytic system for hydrogenation of unsaturated aldehydes; however, the utilization for selective hydrogenation of unsaturated ketones was found inadequate.     

<Emphasis Type="Italic">DegP</Emphasis> and Related Genes as Stress-Markers for <Emphasis Type="Italic">E.Coli</Emphasis>-Viability – Ultra-Sensitive RT-Real-Time PCR

Summary. The study was done to set up an on-line viability test system based on the stress-response of pathogenic E.coli. Fully automated and computerized pathogen detection was achieved via RNA expression monitoring using an high-speed real-time PCR-system with single molecule sensitivity. The device was developed in a collaboration of SAUR, France, the TU Delft (Kluyver Laboratorium – Analytical Biotechnology, Netherlands) and Attophotonics Bioscience, Austria.The automated viability assay is fully hands-off, using a continuous concentration process of the pathogens from litres sample down to tens of millilitres, cell cracking to DNA/RNA solution and further concentration down to a few hundred microlitres. RT-PCR and real-time-PCR are done with a robotic system. DegP found from E.coli to human was selectively induced within the device via heat shock at 50°C. Up to 1000 fold induction was achieved from environmental to heat-shock level. It was proven that degP quantification via RT-real-time PCR provides an excellent basis for multi-organism viability detection.Received September 16, 2002; accepted February 20, 2003 Published online September 15, 2003     

Aryltetralin Lignans from <Emphasis Type="Italic">Linum mucronatum</Emphasis> Bertol. ssp. <Emphasis Type="Italic">mucronatum</Emphasis>

The dried and aerial part of Linum mucronatum ssp. mucronatum was analyzed by gas chromatography-mass spectrometry (GC-MS). Two aryltetralin lignans, podophylloyoxin, 6-methoxypodophylloyoxin, and β-peltatin, were identified. This is the first report of the analysis of L. mucronatum ssp. mucronatum.__________Published in Khimiya Prirodnykh Soedinenii, No. 1, pp. 24–25, January–February, 2005.     

Efficient <Emphasis Type="Italic">Baylis-Hillman</Emphasis> Reaction <Emphasis Type="Italic">via</Emphasis> a 1,4-Diazabicyclo[2.2.2]octane-based Ionic Catalyst

Summary. A novel ionic catalyst, 1-butyl-4-aza-1-azoniabicyclo[2.2.2]octane chloride based on 1,4-diazabicyclo[2.2.2]octane was synthesized and applied in the Baylis-Hillman reaction, which occurred readily at room temperature to afford the corresponding adducts in good yield. The ionic catalyst could be recycled for seven runs without diminution in its catalytic activity.     

Unsteady mass transfer into a sphere under equilibrium condition <Emphasis Type="Italic">y</Emphasis> = <Emphasis Type="Italic">Ax</Emphasis> + <Emphasis Type="Italic">B</Emphasis>

We obtained an analytical solution of a problem of unsteady mass transfer under the equilibrium condition y = Ax + B to compare results with a problem solution in the case of equilibrium condition looking as y = Ax.     

<Emphasis Type="Italic">Ab initio</Emphasis> study of aniline and <Emphasis Type="Italic">n</Emphasis>-propylamine associates with nitrobenzene and <Emphasis Type="Italic">m</Emphasis>-cresol

An ab initio (6-31G**) study of binary associates of aniline and n-propylamine with nitrobenzene and m-cresol has been carried out. The structures corresponding to the total energy minimum of the system have been found for the associates, and their geometrical and energy characteristics have been determined. Basic types of intermolecular interactions have been established, and their effects on the reactivity of the amino group have been investigated.Original Russian Text Copyright © 2004 by I. A. Novakov, V. V. Korolkov, A. I. Pavlyuchko, B. S. Orlinson, and L. A. GribovTranslated from Zhurnal Strukturnoi Khimii, Vol. 45, No. 4, pp. 595–601, July–August, 2004.This revised version was published online in April 2005 with a corrected cover date.     

Synthesis from geraniol of (2<Emphasis Type="Italic">E</Emphasis>,6<Emphasis Type="Italic">E</Emphasis>,10<Emphasis Type="Italic">E</Emphasis>,14<Emphasis Type="Italic">E</Emphasis>)-16-hydroxygeranylgeraniol and some of its derivatives

Several α,ω-bifunctional derivatives of E,E,E-geranylgeraniol were prepared via convergent synthesis starting with geraniol (8), which was converted in three steps into the tetrahydropyranyl ether of 8-chlorogeraniol (9) and 8-hydroxygeranylphenylsulfone (10). Combination of synthons 9 and 10 with subsequent reductive removal of the phenylsulfonyl group produced the tetrahydropyranyl ether of ω-hydroxygeranylgeraniol (5), hydrolysis of which gave exclusively trans-ω-hydroxygeranylgeraniol (1). Derivatives 5–7 of geranylgeraniol were synthesized using standard methods. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 231–234, May–June, 2007.     

Synthesis of 2,3-<Emphasis Type="Italic">cis</Emphasis> Stereomeric Emetamines <Emphasis Type="Italic">via Reissert</Emphasis> Compounds

Summary. Alkylation of Reissert compounds with certain benzoquinolizinone derivatives followed by hydrolytic cleavage afforded the core of the title compounds in a two step sequence. Finally, the lactam intermediates were reduced with DIBAH giving the target compounds, the structural and stereochemical assignments of which were achieved by ¹³C NMR spectroscopy. Part of PhD thesis, LMU München, D