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Some free radical reactions of molecular oxygen / by Rudo Dieter WagnerWagner, Rudolf Dieter January 1981 (has links)
Typescript (photocopy) / v, 151 leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Organic Chemistry, 1982
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The perester-copper salt reaction of cyclic olefins /Phillipou, George. January 1972 (has links) (PDF)
Thesis (M.Sc.) -- University of Adelaide, Dept. of Organic Chemistry, 1973.
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Some free radical reactions of molecular oxygen /Wagner, Rudolf Dieter. January 1981 (has links) (PDF)
Thesis (Ph.D.) -- University of Adelaide, Dept. of Organic Chemistry, 1982. / Typescript (photocopy).
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Development and study of ruthenium catalysts for olefin metathesis displaying cis-dichloro configuration with monodentate ligansGuidone, Stefano January 2014 (has links)
New cis-dichloro ruthenium-based pre-catalysts for olefin metathesis reaction were synthesised. This work was inspired by the report of complex cis-Caz-1 in 2010, a 2nd generation-type pre-catalyst displaying latent character and acknowledged as state-of-the-art for challenging transformation in olefin metathesis. The stability and the reactivity of such species led us to investigate the possibility to perform the catalysis in air with reagent-grade solvents, so that olefin metathesis reaction can be easily carried out in synthetic laboratories avoiding restricting inert conditions (Chapter 2). Next, further modifications of the original scaffold were attempted. Pre-catalyst cis-Caz-1 was reacted with different silver salts leading to new cis-complexes. The first examples of Ru-F species for olefin metathesis reaction are reported in Chapter 3. The phosphite ligand plays a very important role in the cis-Caz-1 scaffold and allowed the formation of the mono and the difluoro complexes selectively. Other silver salts were then employed such as trifluoroacetate, acetate, benzoate and pivalate. In all the studies involving silver salts, the anionic exchange reactions occurring among cis-Ruspecies in solution was observed. Electronic properties rather than sterics were responsible for the selective formation of the mixed complex trifluoroacetate/acetate 55 (Chapter 4). The results obtained with 2nd generation systems prompted us to evaluate triisopropyl phosphite as ligand in 1st generation-type complexes. Similar synergistic effects to complex cis-Caz-1 were observed. The mixed PCy3/P(OiPr)3 complex 56 displayed cis-geometry, high thermal stability and latent character compared to the bis-phosphine analogue Ind-I (Chapter 5). Last, a catalytic and structural study of commercially available pre-catalysts M51TM and M52TM in collaboration with Umicore was carried out together with the Grela group (Chapter 6). These Hoveyda-Grubbs type pre-catalysts showed an interesting activity in ring closing metathesis, allowing the isolation of di- and tri- substituted ring-products at room temperature, as well as in cross metathesis, where some examples of biologically active compounds were obtained.
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Carbene in Reaktionen hochgespannter Kohlenwasserstoffe -theoretische und experimentelle Untersuchungen an ausgewählten SystemenJarosch, Oliver 01 January 1999 (has links)
Die Kinetik der Isomerisierung des [1.1.1]Propellan wurde durch Gasphasenpyrolyse in einem stationären System bestimmt. Die Reaktion ist unimolekular und es wurden folgende Arrhenius-Parameter bestimmt: EA/kcal mol-1 = 39.66 ± 0.52 ; log (A/s-1) = 14.02 ± 0.23. Die Aufklärung des Reaktionsmechanismus gelang durch ab initio-Berechnungen. Es handelt sich um eine stark asynchrone Reaktion, an der die zentralbindung und zwei Seitenbindungen des [1.1.1]Propellan beteiligt sind. Die mit CCSD(T)/6-311G(2d,p)//MP2/6-311G(2d, p) berechnete Aktivierun gs barriere der Gesamtreaktion beträgt EA = 40.1 kcal/mol. Die Carben-Olefin-Carben-Umlagerung von Bicyclo[1.1.1] pentylcarbenen wurde ausgehend von Bicyclo[1.1.1] pentyldiazomethanen in der Gasphase untersucht. Die Pyrolysen erbrachten Bicyclo[2.1.1] hex-2(3)-ene als Produkte einer Carben-Olefin-Carben- Umlagerung mit anschließender 1,2-H- Wanderung. Die Reaktionskaskade wurde an verschieden substituierten Bicyclo[1.1.1]pentylcarbenen mit ab initio- Methoden untersucht. Der Mechanismus konnte durch die Berechnung aller Zwischenstufen und Übergangszustände der Umlagerung, sowie der experimentell beobachteten Konkurrenzreaktionen untermauert werden. Ab initio-Berechnungen zur thermodynamischen Stabilität des Bicyclo[1.1.1]pent-1(2)-ens lieferten eine Spannungsenergie von 140.2 kcal/mol und eine olefinic strain von 73.6 kcal/ mol. Als energetisch günstigste Zerfallsreaktion stellte sich die Umlagerung zum Pent-4-en-1-in heraus. Ein Syntheseversuch des Bicyclo[1.1.1]pent-1(2)-ens durch photochemisch induzierte Norrish-Typ-II-Spaltung des 2-(Bicy clo[1.1.1]pent-1-yl)-1-phenylethanon führte nicht zum Erfolg. / The kinetics of the isomerisation of [1.1.1]propellane was investigated by gasphase pyrolysis in a stationary system. The reaction is unimolecular with the following Arrhenius parameters: EA/kcal mol-1= 39.66 ± 0.52 ; log (A/s-1) = 14.02 ± 0.23. Ab initio calculations of the mechanism showed an asynchronous reaction path involving the central and two side bonds of the [1.1.1]propellane. The activation barrier calculated on the CCSD(T)/6-311G(2d,p)//MP2/6-311G(2d,p) level of theory was 40.1 kcal/mol. The carbene-olefine-carbene rearrangement of bicyclo[1.1.1]pentylcarbenes was studied by gasphase pyrolysis of bicyclo[1.1.1]pentyldiazomethanes. Bicyclo[2.1.1]hex-2(3)-enes could be isolated as products of the rearrangement and an additional 1,2 H shift. Calculations with ab initio and DFT methods of several different substituted bicyclo[1.1.1]pentylcarbenes confirmed the postulated mechanism of the carbene-olefine-carbene rearrangement. DFT calculations of bicyclo[1.1.1]pent-1(2)-ene were carried out giving a strain energy of 140.2 kcal/mol and an olefinic strain of 73.6 kcal/mol. The energetically best isomerisation path of bicyclo[1.1.1]pent-1(2)-ene lead to pent-4-ene-1-ine. The synthesis of bicyclo[1.1.1]pent-1(2)- ene via photochemically induced Norrish type II cleavage of 2-(bicyclo[1.1.1]pent-1-yl)-1-phenylethanone was not successful.
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Optimalizace technologie výroby voskových modelů ve firmě Fimes / Optimization of wax pattern technology in the company FimesŽuja, Jaroslav January 2015 (has links)
This thesis is to evaluate currently used wax and compare its properties with of newly purchased one. Further, it is to evaluate whether the quality is reflected by using "boiled wax'', which is being used as a runner wax. All tests were carried out at the Fimes a. s. In the first part of this thesis, there is a brief description of the lost wax method. This is followed by a decription of wax blends from technology point of view. The experimental part describes the operations from the production of wax patterns, through their dimensional inspection, up until dewaxing process. All the results are noted and compared.
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Optimalizace technologie výroby odlitků ze slitin Al metodou vytavitelného modelu / Optimized manufacturing of aluminium castings by using lost wax technologyTalanda, Ivan January 2012 (has links)
Aim of this diploma thesis is to choose new pattern wax for Fimes a.s. foundry. New wax should substitute old not fully satisfactory pattern wax which caused problems in technological process resulting in increased number of rejects. New pattern wax should eliminate current problems and help foundry with producing large, thin-walled, high-quality castings. Numbers of pattern waxes supplied by world’s leading wax manufacturers were subjected to laboratory tests and pilot study. This diploma thesis is part of project Alfa TA01010766: „Research and development of production technology large, thin and high quality castings of aluminium alloys “
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