Dissertations / Theses on the topic 'Sulfoxides'
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Davies, Clair. "Capillary Electrophoretic Separation of Sulfoxides." TopSCHOLAR®, 1998. http://digitalcommons.wku.edu/theses/338.
Full textKendall, Jackie D. "Synthesis and enantioselective transformations of sulfoxides." Thesis, University of Nottingham, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.311838.
Full textGrainger, Richard Sheridan. "Cycloaddition reactions of C2-symmetric vinyl sulfoxides." Thesis, University of Sheffield, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.387754.
Full textLee, Danny Ka Ming. "Unsaturated sulfinates and sulfoxides in organic synthesis." HKBU Institutional Repository, 1995. http://repository.hkbu.edu.hk/etd_ra/47.
Full textRowen, Catherine Carmel, and n/a. "A New Approach Towards Bicyclo[4.2.0]octan-1-ols: Synthetic and Mechanistic Studies." Griffith University. School of Science, 2003. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20030602.131636.
Full textRowen, Catherine Carmel. "A New Approach Towards Bicyclo[4.2.0]octan-1-ols: Synthetic and Mechanistic Studies." Thesis, Griffith University, 2003. http://hdl.handle.net/10072/367745.
Full textThesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Faculty of Science
School of Science
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Heer, Jag Paul. "New methods of asymmetric oxidation." Thesis, University of Liverpool, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.484195.
Full textChan, Eddy Tsz Tak. "Unsaturated sulfoxides in organic synthesis : a new furan synthesis and total synthesis of isoquinolone alkaloids." HKBU Institutional Repository, 1991. https://repository.hkbu.edu.hk/etd_ra/3.
Full textBanjavciªc, Marko Peter. "Infrared multiple-photon dissociation of small organic sulfoxides." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape7/PQDD_0020/NQ41366.pdf.
Full textMotto, John M. "Ã,ß-unsaturated sulfoxides and sulfinic acid derivatives." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/MQ58363.pdf.
Full textSnyder, Chad. "Enantioseparation of Alkylaryl Sulfoxides Using Capillary Zone Electrophoresis." TopSCHOLAR®, 1999. https://digitalcommons.wku.edu/theses/3040.
Full textJog, Parag V. "Sulfoxides as an intramolecular sulfenylating agent for indoles and diverse applications of the sulfide-sulfoxide redox cycle in organic chemistry /." Available online. Click here, 2005. http://sunshine.lib.mtu.edu/ETD/DISS/jogp/diss.pdf.
Full textBalcells, Badia David. "A Computational Approach to the Synthesis of Chiral Sulfoxides." Doctoral thesis, Universitat Autònoma de Barcelona, 2006. http://hdl.handle.net/10803/3225.
Full textThe synthesis of chiral sulfoxides has been theoretically investigated considering two of the most advanced methods: the vanadium-catalyzed asymmetric oxidation of sulfides with hydrogen peroxide and the DAG method. The mechanism of these reactions was explored at a DFT (Density Functional Theory) level on model systems. The origin of enantioselectivity in the real systems was explored applying hybrid QM/MM (Quantum Mechanics/Molecular Mechanics) methods. The DFT study on the vanadium-catalyzed asymmetric sulfoxidation revealed that this process follows a direct oxygen transfer mechanism in which the substrate is oxidized in a single concerted step. The catalyst is a oxo complex of vanadium(+V) with the oxidant coordinated to the metal as a hydroperoxo ligand. This complex catalyzes the oxidation process reducing the energy barrier from 40.4 to 26.7 kcal/mol. The QM/MM study on the real system showed that there are two possible diastereomers of the catalyst, labeled as A and B, that catalyze the oxidation inducing opposite enantioselectivities. The coexistence of A and B in solution explains the influence of the chiral ligand structure upon enantioselectivity. The DFT study on the DAG method revealed that the dynamic kinetic resolution involved in this transformation follows an addition/elimination mechanism. The key step is the addition in which the alcohol reacts directly with the sulfinyl chloride. This process implies a hydrogen transfer assisted by the base. Triethylamine reduces the barrier of this process from 26.8 to 12.2 kcal/mol. The base also catalyzes the racemization of the sulfinyl chloride reducing the barrier of its pyramidal inversion from 63.4 to 22.3 kcal/mol. The substitution of chlorine by the base was discarded. The QM/MM study of the real system confirmed that the enantioselectivity of this reaction can be easily reversed using different non chiral bases, like pyridine or collidine, as experimentally observed. Our study showed that the steric role of the base becomes critical when pyridine is replaced by collidine. This modification of the base implies an inversion of the chiral distribution of steric bulk around sufur that induces the reversal of enantioselectivity.
Xie, Ning. "Lewis acid catalyzed oxidation of sulfides and sulfoxides by permanganate." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/nq35823.pdf.
Full textJing, Lin. "Chiral Ý-amino sulfoxides and chiral sultams in asymmetric synthesis." HKBU Institutional Repository, 2000. http://repository.hkbu.edu.hk/etd_ra/261.
Full textKennedy, Martina Anne. "Production and application of dioxygenase-catalysed oxidation products from alkenes, arenes and thiaarenes." Thesis, Queen's University Belfast, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.301720.
Full textPaylor, Michael Mark. "Biotransformation of organosulfides with the bacterium Rhodococcus rhodochrous ATCC 19067." Thesis, University of Exeter, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.245300.
Full textRaza, Muhammad Rehail. "Synthesis and chemistry of novel chiral sulfilimines." Thesis, Keele University, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.311151.
Full textYoshikawa, Eduardo Kunio Chinone. "Estudos da Decomposição Térmica de Alguns Sulfóxidos -Funcionalizados." Universidade de São Paulo, 2000. http://www.teses.usp.br/teses/disponiveis/46/46135/tde-04122014-113343/.
Full textThe thermal decomposition of sulfoxides (1)-(4) was performed at ca. 140 °C, until complete consumption of the starting materiais. In each case, the product mixture was analyzed by GC/MS. Authentic samples of identified components were prepared, and in the case of sulfoxides (2)-(4), the crude product composition was determinded by gas chromatography and 1H NMR analyses (internal standard method).Results are as follows: See chart PDF file - For three cases, final products could originate from intermediate hemithioacetals, generated via a thermal Pummerer rearrangement. lhis decomposition mechanism seems to be general for the thermolysis of β-carbonyl sulfoxides. However, sulfoxide (1) decomposes under heating via a radical mechanism.
Boone, Kenneth P. "Photodissociation of (DMSO)₂Fe(II)TPP, (TMSO)₂Fe(II)TPP, and (PSO)₂Fe(II)TPP to form a transient five-coordinate complex as studied using transient resonance Raman spectroscopy /." Connect to full text in OhioLINK ETD Center, 2008. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=toledo1229660779.
Full textTypescript. "Submitted as partial fulfillment of the requirements for the Master of Science Degree in Chemistry." "A thesis entitled"--at head of title. Bibliography: leaves 58-62.
Lam, Kwun Ting. "Chiral acetylenic sulfoxide in asymmetric alkaloid synthesis." HKBU Institutional Repository, 2004. http://repository.hkbu.edu.hk/etd_ra/509.
Full textZhang, Yu-Feng. "Selective Electrocatalytic reduction mediated by Sm(II) : Application to nitroarenes, sulfoxides and phthalimides." Thesis, Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLS596/document.
Full textThe SmI₂ as a single electron transfer reagent has been widely used in organic chemistry since the pioneering works by Kagan. However, the stoichiometric or excess amount of SmI₂ and harmful additives such as HMPA are used normally to enhance the reactivity, moreover, due to the oxygen sensitive, the storage of SmI₂ solution is difficult.Recently, we have developed a new electrocatalytic method based on the electrochemical regeneration of Sm²⁺. Compared to the classic SmI₂ reaction, our process occurred with a catalytic amount of Sm. In the reduction of nitroarenes, it selectively afforded the azo aromatic compounds and anilines depending on different solvents system. Notably, it’s the first time that the Sm²⁺ reaction occurred in the methanol. Normally, the HMPA was the additive in the reduction of sulfoxides by SmI₂. Under our electrocatalytic process, the sulfoxides were converted into sulfides in high chemoselectivity and yield at room temperature without HMPA and protecting atmosphere.The isoindolinone derivatives are series of important products in organic chemistry, the reduction of phthalimides is the most convenient approach to provide them. With alcohols, the unprecedented Sm²⁺ electrocatalyzed reductive alkoxylation of phthalimides was established. Moreover, adding other proton sources, this process afforded the corresponding ω-hydroxylactams and isoindolinones
Mo, Tian. "Chiral acetylenic sulfoxide in asymmetric synthesis ; Enantioselective synthesis of yohimbine alkaloids." HKBU Institutional Repository, 1997. http://repository.hkbu.edu.hk/etd_ra/158.
Full textStrickler, Ricky R. "Sulfinyl chlorides as a source of enantioenriched Ã,ß-unsaturated sulfinate esters and sulfoxides." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/NQ56296.pdf.
Full textBiaggio, Francisco Carlos. "Estudos de sulfenilação de alguns sulfóxidos funcionalizados. Reações de pummerer, catalisada e térmica, de β-ceto, α-metiltio sulfóxidos." Universidade de São Paulo, 1993. http://www.teses.usp.br/teses/disponiveis/46/46135/tde-22062015-104405/.
Full textThe scope of this work consists of a study of reactions of carbanions of functionalyzed sulfoxides with sulfenylating reagents, employing two methods: in the homogeneous phase and by the phase transfer. The literature review, which is presented, shows that although these reactions are new, some other reactions of the carbanions of the functionalyzed sulfoxides, such as alkylations, acylations, condensations with carbonyl compounds and Michael addition, have been already reported. Furthermore, a small number of reactions of sulfinyl carbanions by phase transfer method has been described. The sulfenylation reaction, in the homogeneous phase of the α-sulfinyl aromatic (Ia-d) and cyclic (II) ketones, α-sulfinyl esters (IIIa,b) and thioesters (IVa,b) were performed employing NAH/DMSO and dimethyldissulfide or methyl methanethiosulfonate (MeSO2SMe). Except for the compound (IIb), which showed to be unreactive, in all other cases the monosulfenylated derivatives, not reported previously in the literature, were obtained. The yields of these compounds of 25-90% follow the order: Ib > Ia > IVa > Ic > Id > IIIa > II. The sulfenylation reactions by the phase transfer method were performed employing two different procedures: ion-pair extraction (A) and solid-liquid system (8). The procedure (A) was applied to the compounds Ia, IIIa and IVb, using NaOH/CH2Cl2/Bu4NHSO4 and MeS02SMe. While Ia and IIIa yielded the monosulfenylated derivatives in good yields, IVb remained unchanged. The sulfenylation reactions by procedure (B), using K2CO3/ΦH/TEBA and MeSO2SMe, carried out with the compounds Ia-d, IIIa and IVb, showed to be more satisfactory than by procedure (A), as all compounds afforded the monosulfenylated derivatives. The yield of compound IIIa was only of 20%, but those for other compounds were of 40-67%. The 1H-NMR analysis of the sulfenylated derivatives showed the presence of two diastereomers in equal quantities. It was possible, by replacement of TEBA by a quiral quininium salt, for the case of two sulfinyl ketones (Ia and Ic), to obtain the corresponding sulfenylated derivatives of diastereomeric ratio 4:1. This work presents also, having in application, the thermal decomposition monosulfenylated sulfinyl ketones. The mind the synthetic reaction of the obtention of the α-ketothioesters is interpreted as a non catalyzed Pummerer reaction and may be considered as an alternative method for preparation of these compounds. The thermal decomposition of the non-sulfenylated sulfinyl ketones performed for comparison, showed to be more complex and hardly to be interpreted.
Price, David Wilfred. "Directed hydrogenation of sulphoxides and sulphones." Thesis, University of Oxford, 1992. http://ora.ox.ac.uk/objects/uuid:725ef76d-0cc3-4b6c-afa4-ff95f078b6da.
Full textBeecher, Jean Elizabeth. "Sulfoxidation by microbial monooxygenases." Thesis, University of Exeter, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.244958.
Full textHo, King Fai. "Solid-phase organic synthesis of sulfoxide and chemistry of Ü, Ý-unsaturated-Þ-sultam." HKBU Institutional Repository, 2000. http://repository.hkbu.edu.hk/etd_ra/366.
Full textVahedi, Hooshang. "Catalytic symmetric oxidation of sulfides to sulfoxides mediated by 3-substituted-1,2-benzisothiazole 1,1-dioxides." Thesis, University of Liverpool, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.367257.
Full textKentish, Barnes William. "[2,3]-Stevens rearrangement of vinyl aziridines : the use of sulfoxides as Lewis bases in allylations." Thesis, University of Sussex, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.270559.
Full textSoltau, Carl Peter. "Nitroxide trapping of radical species formed from the reaction of sulfoxides with reactive oxygen species." Thesis, Queensland University of Technology, 2021. https://eprints.qut.edu.au/210339/1/Carl_Soltau_Thesis.pdf.
Full textThaler, Tobias. "Enantiocontrol with Chiral Sulfoxides and Diastereocontrol in the Cross-Couplings of Substituted Cycloalkyl and Piperidinyl Derivatives." Diss., lmu, 2011. http://nbn-resolving.de/urn:nbn:de:bvb:19-134189.
Full textFeizabad, Mohammad Sadegh [Verfasser], and Michael [Akademischer Betreuer] Keusgen. "Synthesis of cysteine sulfoxides and related compounds occurring in wild onions / Mohammad Sadegh Feizabad ; Betreuer: Michael Keusgen." Marburg : Philipps-Universität Marburg, 2019. http://d-nb.info/1198401540/34.
Full textBen, Robert N. "Part~A. Lithiated bicyclic sulfoxides. Part~B. The synthesis of optically active alpha-amino esters via kinetic dynamic resolution." Thesis, University of Ottawa (Canada), 1995. http://hdl.handle.net/10393/10122.
Full textANDRUSKI, STEPHEN WALTER. "I. GEOMETRIC EFFECTS IN SULFUR LONE-PAIR INTERACTIONS. II. SYNTHETIC USES OF SULFOXIMINES, SULFOXIDES AND HEMITHIOKETALS WITH STEREOCHEMICAL CONTROL." Diss., The University of Arizona, 1987. http://hdl.handle.net/10150/184042.
Full textAkinnusi, Taiwo Kayode. "Studies on the stereoselective synthesis of the C17 backbone of the Alternaria toxins using chiral sulfoxide methodology." Diss., Access to E-Thesis, 2000. http://upetd.up.ac.za/thesis/available/etd-03272006-120628/.
Full textEl-Rjoob, Abdul-Wahab. "Dynamic stationary phase modification in reversed-phase high performance liquid chromatography /." free to MU campus, to others for purchase, 1996. http://wwwlib.umi.com/cr/mo/fullcit?p9720536.
Full textThaler, Tobias Johannes Werner [Verfasser], and Paul [Akademischer Betreuer] Knochel. "Enantiocontrol with Chiral Sulfoxides and Diastereocontrol in the Cross-Couplings of Substituted Cycloalkyl and Piperidinyl Derivatives / Tobias Thaler. Betreuer: Paul Knochel." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2011. http://d-nb.info/1015170943/34.
Full textSaikaley, Amanda. "I. Preparation of β-amino Sulfoxides as Potential Selective Connexin Inhibitors II. Synthesis of Isoxylitone Analogues for the Treatment of Epilepsy." Thesis, Université d'Ottawa / University of Ottawa, 2015. http://hdl.handle.net/10393/33424.
Full textNiyama, Emy. "Complexos de dibenzoilmetanatos de terras raras com ligantes R2S=O utilizados como emissores em dispositivos eletroluminescentes." Universidade de São Paulo, 2004. http://www.teses.usp.br/teses/disponiveis/46/46134/tde-26112008-101833/.
Full textThis work presents the synthesis and photo and electroluminescent study of rare earth (RE3+= Eu3+, Gd3+ and Sm3+) β-diketonate (dibenzoylmethane - DBM) complexes with hydrated and sulfoxide ligands (L= benzyl sulfoxide -DBSO, methyl sulfoxide - DMSO, phenyl sulfoxide - DPSO and p-tolylsulfoxide - PTSO). The complexes were characterized by the following techniques: i) elemental analysis of carbon and hydrogen; ii) analysis of RE3+ by complexometric titration; iii) X Rays diffraction patterns; iv) thermal anaiysis; v) IR spectroscopy and vi) scanning electron microscope (SEM). The TG/DTG curves of [RE(DBM)3H2O] and [RE(DBM)3(L)2] complexes present stages of thermal decomposition well defined for the complexes and indicate higher thermal stability when compared with hydrated complex. The IR spectral data indicate that the coordination of organic ligands (DBM and sulfoxides) to RE3+ ions occur through the oxygen atoms. The photomicrographs obtained from films indicate which vacuum and solution techniques can give films with good quality. The X Rays diffraction patterns suggest that the [RE(DBM)3(L)2] complexes are in the same isomorfic series. The emission spectra of the complexes exhibit the 5D0→7FJ transitions (J=0-4) from the Eu3+ ion and 4G5/2→6HJ (J=5/2-11/2) from the Sm3+ ion, which follow the selection rule 2J+1 and J+½, respectively. The high values of the Ω2 intensity parameters of Eu3+ complexes indicate that the RE ion is in a highly polarizable chemical environment. The luminescence decay curves show a mono- exponential behavior for the complexes indicating the inexistence of other channel depopulation. The lifetimes (τ) values of the emitting level from RE3+ -complexes with sulfoxide ligands are higher than hydrated complexes. The complexes containing sulfoxide ligands present higher values of emission quanturn efficiency (η) and quantum yield (q) than hydrated complexes due OH oscillators. The emission spectra of [Eu(DBM)3(PTSO)2] in solutions and fiIms show the similar spectrum profles compared with that in solid state. These results indicate device construction could be realized from solution techniques as spin coating, dip coating, silk screening and ink jetting. The phosphorescence spectra of the Gd3+-complexes show broaden bands arising from the triplet states (T) of the DBM-(~486nm); which are absent in the emission spectra for the RE3+ complexes indicating an efficient energy transfer from the (T) state of the ligand to the emitting level 5D0 and 4G5/2 of Eu3+ and Sm3+ ions, respecfively. The complex [Eu(DBM)3(PTSO)2] was utilized as emitting layer of red light in construction of electroluminescent (EL) devices. These devices were constructed through Physical Vapour Deposition (PVD) technique and they present the following structures: (1) ITO / MTCD / [Eu(DBM)3(PTSO)2] / Alq3 / AI; (2) ITO / NPB / [Eu(DBM)3(PTSO)2] / Alq3 / Al; e (3) ITO / NPB / [Eu(DBM)3(PTSO)2] / Al The MTCD =1-( 3-methylphenyl)-1,2,3,4-tetrahydroquinoline-6-carboxyaldehyde-1,1-diphenyilhydrazone; and NPB =N,N-diphenyl-N,N-bis(1-naphthyl)-1,1-biphenyl-4,4\'-diamine, act as hole transporting layer (HTL). The Alq3, (8-hydroxyquinoline aluminum) thin film act as electron transporting layer (ETL). The [Eu(DBM)3(PTSO)2] complex shows electron transport properties; which tend to reduce the cost of production of this type of organic electroluminescent (EL) devices. The last layer is the Al (aluminum) thin íilm, which act as cathode and reflector of emitted light. The CIE (Commission Internationale de l\'Eclairage) coordinates of the EL devices show contributions of emission from the NPB (400-600 nm) and 5D1→ 7F1 transition from the Eu3+ ion. This problem can be solved with alteration h the architecture of the device (NPB, MTCD, TPD and Alq3.
White, Stephen A. "A study of the diastereoselectivity of [gamma]-chiral-[alpha], [beta]-unsaturated sulfoxides and sulfones in the Michael reaction with lithium dimethyl cuprate." Diss., Georgia Institute of Technology, 1986. http://hdl.handle.net/1853/25972.
Full textChen, Yi. "SYNTHESIS OF THE PENTAVALENT IODINE COMPOUND, DIPHENYLIODOSYL TOSYLATE, AND ITS USE FOR THE OXIDATION OF SULFIDES." University of Akron / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=akron1186450610.
Full textJivishov, Emil [Verfasser], and Michael [Akademischer Betreuer] Keusgen. "Investigations on Wild Allium Species. Part I: Cysteine Sulfoxides of Flowers. Part 2: Anticancer Activity of Bulb Extracts. / Emil Jivishov ; Betreuer: Michael Keusgen." Marburg : Philipps-Universität Marburg, 2019. http://d-nb.info/1176106791/34.
Full textCosta, Luiz Antonio Mendonça Alves da. "Reações de oxidação e hidrolise por microrganismos nos metodos de biocatalise e de biorremediação." [s.n.], 2005. http://repositorio.unicamp.br/jspui/handle/REPOSIP/249096.
Full textTese (doutorado) - Universidade Estadual de Campinas, Instituto de Quimica
Made available in DSpace on 2018-08-04T15:13:44Z (GMT). No. of bitstreams: 1 Costa_LuizAntonioMendoncaAlvesda_D.pdf: 24416441 bytes, checksum: bec02c6b51213d77af83bf869644c046 (MD5) Previous issue date: 2005
Resumo: O presente trabalho foi dividido em dois projetos: a avaliação do potencial biocatalítico de microrganismos isolados da abelha Trigonna sp e o estudo de biorremediação de ambiente contaminado por Alachlor®. A atividade catalítica de oxidação de sulfeto e a hidrólise de éster sulfínico de 12 linhagens de fungos foi avaliada durante a primeira parte deste trabalho, dentre das quais, 8 linhagens foram isoladas do corpo da abelha Trigonna sp em trabalhos anteriores do nosso grupo. Os melhores microrganismos na oxidação enantiosseletiva do etil fenil sulfeto foram os Fungo CCT 5553 e Cladosporium sp. CBMAI 0210 que produziram o (S)-etil-fenil-sulfóxido (ee > 99%) e (R)-etil-fenil-sulfóxido (ee 97%), respectivamente. O (S)-etil-fenil-sulfóxido (ee > 92%) foi aplicado na síntese da S-(+)-4-metil-3-heptanona, feromônio de alarme da formiga do gênero Atta, mas uma racemização durante a eliminação do grupo sulfinila impossibilitou a síntese total. Para a resolução enzimática de (±)-benzenossulfinato de cicloexila foi selecionado os fungos Penicillium sp. CBMAI 0208 e Aspergillus ochraceus CBMAI 0211 ambos fornecendo os produtos com excessos enantioméricos > 99%. Na segunda etapa, avaliou-se a capacidade de degradação do pesticida Alachlor® de 6 linhagens de bactérias (Streptomyces sp.) e as estruturas dos produtos de degradação foram sugeridas baseados em seus padrões de fragmentação. Entre esses 8-etil-quinolina e N-metil-8-etil-indol nunca foram citados nos estudos de biodegradação do Alachlor®.
Abstract: The work presented in this thesis is divided into two projects: the evaluation of the biocatalytic potential of microorganisms isolated from Trigonna bee and those deposited in two brazilian collections and bioremediation of Alachlor contamined soil. The sulfide oxidation and sulfinic esters hydrolysis catalytic activity was screened using 12 different fungi strains, 8 of which were previously isolated from a Trigonna sp. bee. The best microorganisms for the enantioselective oxidation of ethyl phenyl sulfide were Fungus CCT 5553 and Cladosporium sp. CBMAI 0210 WHICH PRODUCED (R)-ethyl phenyl sulfoxide (ee 97%) and (S)-ethyl phenyl sulfoxide (ee > 99%) respectively. The chiral (S)-ethyl phenyl sulfoxide which was applied in the synthesis of S-(+)-4-methyl-3-heptanone, ant alarm pheromone (genus Atta), of but racemization during sulfinyl group elimination step precluded the total asymmetric synthesis. For the enzymatic resolution of the cyclohexyl (±)-benzenosulfinate we have selected Penicillium sp. CBMAI 0208 and Aspergillus ochraceus CBMAI 0211 both with the capacity of resolving the sulfinate in over 99 enantiomeric excess. In the second part, the Alachlor® degradation potential of 6 bacterium strains (Streptomyces sp.) was evaluated and the structures of biodegradation products were suggested based on their mass fragmentation patterns. Among these 8-ethyl-quinoline and N-methyl-8-ethyl-indole have never been mentioned as Alachlor biodegradation products before.
Doutorado
Quimica Organica
Doutor em Quimica
Serreqi, Alessio N. "Hydrolase catalyzed resolutions of enantiomers : a structural basis for the chiral preference of lipases : preparation of enantiomerically-pure phosphines, phospine oxides, sulfoxides and pipecolic acid." Thesis, McGill University, 1994. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=28918.
Full textLipases and esterases can resolve compounds with phosphorus and sulfur stereocenters by hydrolysis of a pendant acetoxy group. Both CRL and cholesterol esterase have high selectivity for (2-acetoxy-1-naphthyl)methylphenylphosphine oxide. They resolved this substrate with and E of 81 and 32 respectively. A synthetic scale resolution of this substrate with subsequent recrystallization and chemical transformation followed by stereospecific reduction gave both enantiomers of (2-methoxy-1-naphthyl)methylphenyl-phosphine with 96-97% ee. This chiral phosphine is potentially useful in asymmetric syntheses.
CE is the most selective enzyme for the sulfur substrates tested but these enantioselectivities were moderate, E's ranged from 5 to 25. From the CE resolution of the phosphorus and sulfur compounds and others we propose an empirical model that predicts which enatiomer reacts faster. The model is based on the size of the substituents and their conformational preferences.
Crude Aspergillus niger resolves esters of pipecolic acid with an E of 20 $ pm$ 4. A simple partial purification of ANL by fractional precipitation with ammonium sulfate increased the enantioselectivity to $>$100. The partially purified ANL can be used in a synthetic scale resolution of ($ pm$)-n-octyl pipecolate to give (S)-($-$)-pipecolic acid (93% ee) and (R)-(+)-pipecolic acid (97% ee).
Stoffregen, Stacey Anne. "Palladium(II) and platinum(II) synthetic peptidases residue- and sequence-selective hydrolysis and the photochemistry of sulfoxides, S,C-sulfonium ylides, and sulfilimines: unimolecular bond cleavage/." [Ames, Iowa : Iowa State University], 2007.
Find full textYalcouye, Boubacar. "Synthèse atropo-sélective de la partie biarylique de la (-)-stéganacine via le couplage croisé de Suzuki-Miyaura et le couplage ARYNE." Thesis, Strasbourg, 2014. http://www.theses.fr/2014STRAF059.
Full textThe interesting biological properties of axially chiral biaryls and the challenge of Csp2-Csp2 bond formation ofthe biaryl motif have aroused keen interest among synthetic organic chemists. The axially chiral biaryls areprivileged structures in medicinal chemistry and in asymmetric catalysis. The goal of our research is based onthe control of the axial chirality of (-)-steganacin using two differents atropo-selective approaches: Suzuki-Miyaura cross-coupling (in presence of transition metals), and ARYNE coupling (without any transitionmetals). The atropo-diastereoselective Suzuki-Miyaura cross-coupling was carried out using enantiopure β-hydroxysulfoxydes as chiral auxiliary. The resulting diastereopure biaryl was converted into an intermediatereported in the literature without any epimerization of axial chirality. The second approach was the atropodiastereoselectiveARYNE coupling which was tested for the first time with the enantiopure p-tolylsulfoxyde.However, we encountered a problem due to lack of reactivity of lithiated arylsulfoxide. Finally, the axialchirality of (-)-steganacin was controlled using oxazolines as chiral auxiliary
Malacea, Raluca. "Utilisation de ligands bifonctionnels chiraux pour la catalyse asymétrique impliquant des complexes d'hydrures." Toulouse 3, 2006. http://www.theses.fr/2006TOU30054.
Full textAfter a bibliographic introduction on bifonctional P,N and P,S ligands used in asymmetric catalysis (Chapter I), in the chapter II is described the synthesis of new compounds P,P-diaminoalkyl-phosphine and P,P,P-triamino-phosphine from chiral damines and their application in styrene hydroformylation. In the third chapter, we studied the coordination chemistry of chiral phosphine-thioether ferrocenic ligands with platinum, palladium, iridium, rhodium and ruthenium and we obtained a great variety of complexes. The configuration of the sulphur atom, which became asymmetric after coordination, is totally controlled by the planar chirality of ferrocene. Iridium complexes gave high activity and excellent enantioselectivity (e. E. Up to 99%) in the asymmetric hydrogenation of ketones
Itsenko, Oleksiy. "Photoinitiated Radical Carbonylation Using [11C]Carbon Monoxide : 11C-Labelling of Aliphatic Carboxylic Acids, Esters, and Amides." Doctoral thesis, Uppsala universitet, Kemiska institutionen, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-6021.
Full textItsenko, Oleksiy. "Photoinitiated Radical Carbonylation Using [11C]Carbon Monoxide : 11C-Labelling of Aliphatic Carboxylic Acids, Esters, and Amides." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis: Univ.-bibl. [distributör], 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-6021.
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