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Showing 1 to 20 of 134 for “"540 Chemie"”.
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Alkalimetallmanganchalkogenide : Synthese, Struktur und Magnetismus
Subject of this dissertation are the correlation between structure and magnetism of some Alkalimetal-Manganese-Chalcogenids. The compounds K2Mn3S4 and Rb2Mn3Te4 were synthesised and the structure were determined by single crystal X-Ray-Diffraction. The spin-structures of the compounds K2Mn3S4 and …
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Darstellung von Telechelen auf Acrylat- und Methacrylatbasis durch 'atom transfer radical polymerisation' und 'atom transfer radical addition'
The present thesis deals with the preparation of telechelics on the basis of acrylic and methacrylic monomers using atom transfer radical polymerisation and atom transfer radical addition. The telechelics can be used as prepolymers in polyaddition and polycondensation reactions. Polymerisation of …
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Enantioselektive Pi-Komplexierung durch intramolekulare Chiralitätsübertragung aus CpTi-Aminosäure-Komplexen
This work contains new synthesis of chiral CpTiL*-complexes where L* = amino acid, lactic acid or phenylethylamine. With these complexes the possibility for the preparation of enantiomerically enriched "titanocenes" [CpCppcTiCl2], where Cppc is a prochiral cyclopentadienide, was explored. In …
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Asymmetrische Synthese funktionalisierter Homoallyl- und Homopropargylalkohole mittels der Sulfoximin-Route
This dissertation describes new methods of asymmetric synthesis of diastereomeric and enantiomeric pure allylic alcohols. Via the sulfoximine-route by Gais et al. new chiral homoallyllic alcohols were synthesized. Elimination of the sulfoximine-group lead to optically pure homopropargylic alcohols. …
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Asymmetrische Synthese und stereoselektive Substitution allylischer Sulfoximin-funktionalisierter Homoallylalkohole
Enantiopure acyclic (E)- and (Z)-configured allylic sulfoximines have been synthesized from N,S-dimethyl-S-phenylsulfoximine and aldehydes via the addition-elimination-isomerization route. Titanation of lithiated (E)- and (Z)-configured allylic sulfoximines with Chlortrisdiethylanimotitan and …
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Molekulardynamische Simulation von Alkalinitratschmelzen
Subject of this thesis is molecular dynamics simulation of molten alkali nitrate. The well-known Born-Mayer-Huggins interaction potentials are improved by calculating the pressure of the melt and adjusting some Van-der-Waals-type attractive addition. These modified potentials are then used to …
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Biocompatible ultrathin coatings from isocyanate terminated star PEG prepolymers
In this thesis the synthesis of end group terminated 6 arm starpolymers is prescribed. To achieve this different hydroxyl terminated star polymers were treated with isophorone diisocyanate, acrylic acid chloride or divinyl sulfone respectively. Important therby was the surpression of the unwanted …
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Asymmetric synthesis of (+)-altholactone, a styryllactone from various goniothalamus species
A consice and stereoselective route to highly functionalised a,b-unsaturated-d-lactone, (+)-altholactone (1), from the well-established 1,3-diol building block, dioxanone (2,2-dimethyl-1,3-dioxan-5-one) 4, is described. This approach is based on establishment of the chiral centres by applying a …
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Planar chirale Metallocene
The element of planar chirality turned out to be of special importance to achieve high enantioselectivities in various asymmetric processes. In the course of this PhD thesis, the sulfoximine unit was established as a new chiral ortho-directing group for ferrocenes. By variation of the metal …
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Synthese von maßgeschneiderten Polymeren auf Methacrylatbasis durch 'Atom Transfer Radical Polymerisation' (ATRP)
The present thesis deals with the synthesis of tailored polymers based on methacrylates. To control the polymerisation process, the atom transfer radical polymerisation (ATRP) method was used. On the one hand, the thesis describes the preparation of polymers for the application in a composite. On …
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Asymmetrische Dihydroxylierung (AD) und asymmetrische Aminohydroxylierung (AA) mit immobilisierten Alkaloiden
The Asymmetric Dihydroxylation (AD) and Asymmetric Aminohydroxylation (AA) of olefins introduced by Sharpless represent efficient methods for the preparation of diols respectively vicinal aminoalcohols. Within this thesis the attachment of different ligand types (pyrimidine-, …
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Synthese substituierter chiraler [2.2]Paracyclophane und deren Einsatz in asymmetrischen Katalysereaktionen
The element of planar chirality turned out to be of special importance to achieve high enantioselectivities in various asymmetric processes. However, only few planar chiral compounds based on [2.2]paracyclophane were tested as ligands in asymmetric catalytic reactions. In the course of this PhD …
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Synthese, Charakterisierung und thermischer Abbau von Copolymeren aus THF und funktionalisierten Oxiranen
In the present thesis copolymers of thf and differently substituted oxiranes were prepared via kationic ring-opening copolymerization. Oxirane comonomers used were ethylene oxide, propylene oxide, alkylglycidyl ethers, alkyl 3,4-epoxybutanoate and glycidyl acetate. Copolymers with different ranges …
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Pd-katalysierte asymmetrische Synthese allylischer Sulfone und Stereochemie der Lithiumsalze chiraler allylischer Alpha-tert-Butylsulfonyl-Carbanionen
The Pd(0)-catalyzed allylic sulfonation of allylic substrates with Lithium tert-Butylsulfinate in presence of chiral bisphospines leads to chiral allylic tert-Butylallylsulfones in high yields up to 96% and selectivities up to 98%. Deprotonation of said compounds in alpha-position to their …
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Bestimmung der Lösungsstruktur der dritten Extrazellulärdomäne des Signaltransduktors gp130 mittels mehrdimensionaler heteronuklearer NMR-Spektroskopie
The signal transducer gp130: Solution structure of the carboxy-terminal domain of the cytokin receptor homology region. The transmembrane glycoprotein gp130 is the common signal transducing receptor subunit of the interleukin-6-type cytokines. It is a member of the cytokin-receptor superfamily …
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