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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

First principles studies of transition metal surfaces : the effect of an external field on surface electronic properties and surface energetics /

Feng, Yongjia. January 2003 (has links)
Thesis (Ph. D.)--Hong Kong University of Science and Technology, 2003. / Includes bibliographical references (leaves 106-110). Also available in electronic version. Access restricted to campus users.
2

New amine-substituted cyclopentadienyl and indenyl ligands

Marsh, Sarah Margaret Beatrice January 1997 (has links)
This thesis concerns the new amine-substituted cyclopentadiene and indene ligands C(_5)H(_5)(CH(_2))(_3)N((^t)Bu)H and C(_9)H(_7)(CH(_2))(_3)N((^t)Bu)H which can co-ordinate to a metal through all five carbon atoms of the five-membered ring (η(^5)) and/ or through the nitrogen (σ). Chapter 1 reviews the recent literature concerning Lewis-base functionalised cyclopentadienyl and indenyl ligands and their compounds with s-, p-, d- and f-block metals. Chapter 2 contains a brief review of possible synthetic routes to amine-substituted cyclopentadienyl and indenyl ligands with some examples from the recent literature, and a detailed account of the synthesis of C(_5)H(_5)(CH(_2))(_3)N((^t)Bu)H and C(_9)H(_7)(CH(_2))(_3)N((^t)Bu)H. The amino alcohol (^t)BuNH(CH(_2))(_3) OH was synthesised by the conjugate addition of (^t)BuNH(_2) to ethyl acrylate and reduction of the product ester (^t)BuNH(CH(_2))(_2)C0(_2)Et using LiAIH(_4). (^t)BuNH(CH(_2))(_3)OH was converted into (^t)BuNH(CH(_2))(_3)Br.HBr and (^t)BuNH(CH(_2)(_3)Cl.HCl by reaction with HBr or SOCI(_2). Reaction between (^t)BuNH(CH(_2))(_3)C1.HC1 and two equivalents of Na(C(_5)H(_5)) gave C(_5)H(_5)(CH(_2))(_3)N((^t)Bu)H in good yield. Treatment of (^1)BuNH(CH(_2))(_3)C1.HC1 with excess NaOH followed by reaction with Li(C(_9)H(_7)) gave C(_9)H(_7)(CH(_2))(_3)N((^t)Bu)H, also in good yield. Chapter 3 describes the synthesis of various main group and iron compounds of C(_5)H(_5)(CH(_2))(_3)N((^t)Bu)H and C(_9)H(_7)(CH(_2))(_3)N((^t)Bu)H. Lithium salts Li[C(_5)H(_4)(CH(_2))(_3)N((^t)Bu)H], Li[C(_5)H(_4)(CH(_2))(_3)N((^t)Bu)]Li, Li[C(_9)H(_6)(CH(_2))(_3)N((^t)Bu)H] and Li[C(_9)H(_6)(CH(_2))(_3)N((^t)Bu)]Li were prepared for use as reactive intermediates and Li[C(_5)H(_4)(CH(_2))(_3)N((^t)Bu)H] was characterised as its THF-adduct by (^t)H NMR spectroscopy. The silyl derivatives (Me(_3)Si)C(_5)H(_4)(CH(_2))(_3)NH(^t)Bu and (Me(_3)Si)C(_5)H(_4)(CH(_2))(_3)N((^t)Bu)SiMe(_3) were synthesised and characterised by NMR spectroscopy, and (Me(_3)Si)C(_9)H(_6)(CH(_6))(_3)N((^t)Bu)H and (Me(_3)Si)C(_9)H(_6)(CH(_2))(_3)N((^t)Bu)(SiMe(_3)) were also synthesised. The anune-substituted ferrocene Fe{η(^5)-C(_5)H(_4)(CH(_2))(_3)N((^t)Bu)H}(_2) was synthesised and oxidised to the corresponding ferricenium ion which was isolated as its PF(_6)(^-) salt. Exploratory work was carried out into the preparation of heterobimetallic species by reaction between Fe{η(^5)-C(_5)H(_4)(CH(_2))(_3)N((^t)Bu)H}(_2) and MX(_2) (M = Co, Ni, X = CI, M = Mn, X = Br). The substituted bis(indenyl) iron(II) complex Fe{η(^5)-C(_9)H(_6)(CH(_2))(_3)N((^t)Bu)H}(_2) was also synthesised. Chapter 4 is an account of the chemistry of {η(^5) :σ-C(_5)H(_4) (CH(_2))(_3)N(^t)Bu}Ti(NMe(-2))(_2) which was synthesised by an aminolysis reaction between C(_5)H(_5)(CH(_2))(_3)NH(^t)Bu and Ti(NMe(_2))(_4) Reaction between this compound and various weak acids gave a range of new compounds including{η(^5):σ-C(_5)H(_4)(CH(_2))(-3)N(^t)Bu} Ti(O(^t)Pr)(_2), {η(^5):σ-C(_5)H(_4)(CH(_2))(_3)N(^t)Bu)(_2), {η(^5):σC, {η(^5):σ-C(_5)H(_4)(CH(_2))(_3)N(^t)Bu}Ti(C(_5)H(_5))(NMe(_2)) , {η(^5):σ-C(_5)H(_4)(CH(_2))(_3)N(^t)Bu}Ti(SnBu(_3))(_z) and the imido-bridged dimer [{η(^5):σ-C(_5)H(_4)(CH(_2))(_3)N(^t)Bu}Ti(NHPh)](_2)(µ-NPh)2, the X-ray structure of which is reported. Chapter 5 describes the experimental procedures used, and chapter 6 gives lists of characterising data for each compound. Appendix A gives details of the methods used for magnetic susceptibility determinations; appendix B lists X-ray crystallographic data for [ {η(^5):σ-C(_5)H(_4)(CH(_2))(_3)N(^t)Bu}Ti(NHPh)](_2)(µ-NPh)(_2) and appendix C lists departmental colloquia attended.
3

Preparação e estudo termoanalítico dos 4-Clorobenzalpiruvatos de lantanídeos (III) e de ítrio (III) no estado sólido

Fernandes, Nedja Suely [UNESP] 08 February 2001 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:35:05Z (GMT). No. of bitstreams: 0 Previous issue date: 2001-02-08Bitstream added on 2014-06-13T20:06:23Z : No. of bitstreams: 1 fernandes_ns_dr_araiq.pdf: 3831286 bytes, checksum: 1e94d572a9dbeea49beace1001cfce35 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / No presente trabalho os 4-clorobenzalpiruvatos de Lantanídeos exceto (promécio) e de ítrio foram sintetizados adicionando-se à solução aquosa do ligante 4-clorobenzalpiruvato de sódio (Na- 4ClBP), solução aquosa dos respectivos cloretos metálicos, exceto para o composto de cério, para o qual usou-se o nitrato de cério. Os precipitados obtidos foram lavados com água destilada para a eliminação de interferentes, secos a temperatura ambiente e armazenados em dessecador com atmosfera rarefeita sobre cloreto de cálcio anidro. Para a caracterização dos compostos obtidos foram utilizadas as técnicas de Análise Elementar, Espectroscopia de Absorção na região do infravermelho, Difratometria de raios X pelo método do pó e complexometria com EDTA. A espectroscopia de absorção na região do infravermelho sugere que a coordenação metal – ligante ocorre pelo grupo carboxilato e carbonila cetônica. Na determinação da estequiometria, estabilidade térmica, bem como o estudo da desidratação foram utilizadas as técnicas: Termogravimetria (TG), Termogravimetria Derivada (DTG), Calorimetria Exploratória Diferencial (DSC) e Termogravimetria/Análise Térmica Diferencial simultâneo. As curvas TG, DTG e DSC foram obtidas utilizando-se o sistema Mettler em atmosfera dinâmica de ar sintético e CO2 com fluxo de 150 e 90 mL min -1, respectivamente. Utilizou-se razão de aquecimento de 10 o C min -1, massa de amostra da ordem de 7 mg, cadinho de α - Al2O3 e faixa de temperatura de 30 a 900 o C para as curvas TG, DTG e cadinho de alumínio com tampa perfurada e faixa de temperatura de 30 a 600 o C para as curvas DSC. As curvas TG/DTA foram obtidas utilizando-se o equipamento da TA Instruments modelo SDT 2960 em atmosfera dinâmica de ar sintético com fluxo de 100 mL min –1, razão de aquecimento de 20 o C min –1, cadinho de alumina para a amostra e referência e massa... / In the present work the lanthanide 4-chlorobenzylidenepyruvates, except prometium, and yttrium were synthesized by addition of aqueous solutions of the respective metal chlorides, except for the cerium compound that was cerium nitrate, to the aqueous solution of the ligand sodium 4-chlorobenzylidenepyruvate (Na-4-ClBP). The precipitates obtained were filtered, washed with distilled water until elimination of the chloride or nitrate ions, dried at room temperature and kept in a desiccator over anhydrous calcium chloride and with rarefied atmosphere. The compounds obtained were characterized by elemental analyses, infrared spectroscopy, X Ray powder diffractometry and complexometry with EDTA. The infrared spectroscopy suggest that the metal – ligand coordination occur for the carboxylate group and ketonic carbonyl. Thermogravimetry, derivative thermogravimetry (TG, DTG), Differential scanning calorimetry (DSC) and simultaneous thermogravimetry, differential thermal analysis (TG/DTA) were used to determine the stoichiometry, thermal stability as well as the dehydration study. TG, DTG and DSC curves were obtained using a Mettler TA – 4000 thermal analyses system in dynamical air and CO2 flowing at 150 and 90 mL min –1, respectively. At heating rate of 10 o C min –1, samples of ca. 7 mg in alumina crucible, temperature ranging from 30 to 900 o C for the TG and DTG, and in aluminium crucible with perforated cover from 30 and 600 o C, for the DSC curves. TG/DTA curves were obtained using a TA Instruments model SDT 2960 with an air flux of 100 mL min –1, a heating rate of 20 o C min –1, alumina crucible for the sample and reference and with samples of ca. 7 mg. Dehydration enthalpies were determined from the DSC curves for the La, Ce, Pr, Sm, Tm, Er, Yb and Y compounds, as representative of the Lanthanide Series (Ln). The heating rate of 10 o C min –1, samples of ca. 5 mg,...(Complete abstract, click electronic access below)
4

Trimethylsilylated allyl complexes of groups I-V formation, structure, and catalytic reactions /

White, Rosemary Elaine. January 2006 (has links)
Thesis (Ph. D. in Chemistry)--Vanderbilt University, Dec. 2006. / Title from title screen. Includes bibliographical references.
5

Preparação e estudo termoanalítico dos 4-Clorobenzalpiruvatos de lantanídeos (III) e de ítrio (III) no estado sólido /

Fernandes, Nedja Suely. January 2001 (has links)
Resumo: No presente trabalho os 4-clorobenzalpiruvatos de Lantanídeos exceto (promécio) e de ítrio foram sintetizados adicionando-se à solução aquosa do ligante 4-clorobenzalpiruvato de sódio (Na- 4ClBP), solução aquosa dos respectivos cloretos metálicos, exceto para o composto de cério, para o qual usou-se o nitrato de cério. Os precipitados obtidos foram lavados com água destilada para a eliminação de interferentes, secos a temperatura ambiente e armazenados em dessecador com atmosfera rarefeita sobre cloreto de cálcio anidro. Para a caracterização dos compostos obtidos foram utilizadas as técnicas de Análise Elementar, Espectroscopia de Absorção na região do infravermelho, Difratometria de raios X pelo método do pó e complexometria com EDTA. A espectroscopia de absorção na região do infravermelho sugere que a coordenação metal - ligante ocorre pelo grupo carboxilato e carbonila cetônica. Na determinação da estequiometria, estabilidade térmica, bem como o estudo da desidratação foram utilizadas as técnicas: Termogravimetria (TG), Termogravimetria Derivada (DTG), Calorimetria Exploratória Diferencial (DSC) e Termogravimetria/Análise Térmica Diferencial simultâneo. As curvas TG, DTG e DSC foram obtidas utilizando-se o sistema Mettler em atmosfera dinâmica de ar sintético e CO2 com fluxo de 150 e 90 mL min -1, respectivamente. Utilizou-se razão de aquecimento de 10 o C min -1, massa de amostra da ordem de 7 mg, cadinho de α - Al2O3 e faixa de temperatura de 30 a 900 o C para as curvas TG, DTG e cadinho de alumínio com tampa perfurada e faixa de temperatura de 30 a 600 o C para as curvas DSC. As curvas TG/DTA foram obtidas utilizando-se o equipamento da TA Instruments modelo SDT 2960 em atmosfera dinâmica de ar sintético com fluxo de 100 mL min -1, razão de aquecimento de 20 o C min -1, cadinho de alumina para a amostra e referência e massa...(Resumo completo, clicar acesso eletrônico abaixo) / Abstract: In the present work the lanthanide 4-chlorobenzylidenepyruvates, except prometium, and yttrium were synthesized by addition of aqueous solutions of the respective metal chlorides, except for the cerium compound that was cerium nitrate, to the aqueous solution of the ligand sodium 4-chlorobenzylidenepyruvate (Na-4-ClBP). The precipitates obtained were filtered, washed with distilled water until elimination of the chloride or nitrate ions, dried at room temperature and kept in a desiccator over anhydrous calcium chloride and with rarefied atmosphere. The compounds obtained were characterized by elemental analyses, infrared spectroscopy, X Ray powder diffractometry and complexometry with EDTA. The infrared spectroscopy suggest that the metal - ligand coordination occur for the carboxylate group and ketonic carbonyl. Thermogravimetry, derivative thermogravimetry (TG, DTG), Differential scanning calorimetry (DSC) and simultaneous thermogravimetry, differential thermal analysis (TG/DTA) were used to determine the stoichiometry, thermal stability as well as the dehydration study. TG, DTG and DSC curves were obtained using a Mettler TA - 4000 thermal analyses system in dynamical air and CO2 flowing at 150 and 90 mL min -1, respectively. At heating rate of 10 o C min -1, samples of ca. 7 mg in alumina crucible, temperature ranging from 30 to 900 o C for the TG and DTG, and in aluminium crucible with perforated cover from 30 and 600 o C, for the DSC curves. TG/DTA curves were obtained using a TA Instruments model SDT 2960 with an air flux of 100 mL min -1, a heating rate of 20 o C min -1, alumina crucible for the sample and reference and with samples of ca. 7 mg. Dehydration enthalpies were determined from the DSC curves for the La, Ce, Pr, Sm, Tm, Er, Yb and Y compounds, as representative of the Lanthanide Series (Ln). The heating rate of 10 o C min -1, samples of ca. 5 mg,...(Complete abstract, click electronic access below) / Orientador: Massao Ionashiro / Coorientador: Fernando Luís Fertonani / Banca: Cristo Bladimiros Melios / Banca: Geraldo Vicentini / Banca: Antonio Souza de Araujo / Banca: Afonso Rodrigues Aquino / Doutor
6

Preparação e estudo termoanalítico dos 2-clorobenzalpiruvatos de alumínio, de gálio, de índio e de escândio no estado sólido /

Bannach, Gilbert January 2003 (has links)
Orientador: Massao Ionashiro / Banca: Éder Tadeu Gomes Cavalheiro / Banca: João Olimpio Tognolli / Resumo: No presente trabalho, os 2-clorobenzalpiruvatos de alumínio, gálio, índio e escândio foram sintetizados, misturando-se soluções aquosas do ligante com as dos respectivos nitratos até total precipitação dos íons metálicos. Os precipitados foram lavados com água destilada até total eliminação dos íons nitratos, filtrados, secos e mantidos em dessecador sob cloreto de cálcio anidro. Na caracterização, verificação da estabilidade e o estudo da decomposição térmica desses compostos foram utilizados as técnicas de análise elementar, espectroscopia de absorção na região do infravermelho, difratometria de raios X pelo método do pó e termogravimetria-analise térmica diferencial simultânea (TG-DTA). Os espectros de absorção na região do infravermelho permitiram sugerir que a coordenação do ligante aos íons metálicos ocorre pelo carboxilato de forma unidentada, formando também ligações em ponte e sem a participação da carbonila cetônica. Os difratogramas de raios X pelo método do pó mostram que todas os compostos sintetizados foram obtidos no estado não cristalino. Os resultados analíticos e termoanalíticos permitiram estabelecer a formula geral M(2-Cl-BP)3.nH2O, onde M= Al, Ga, In, Sc e n= 2; 2; 1,5; 2,5; respectivamente. As curvas TG-DTA simultâneas desses compostos mostram que a desidratação ocorre em uma única etapa, seguida da decomposição térmica sem evidência de formação de compostos anidros estáveis. Essas curvas também mostram que a decomposição térmica ocorre através de duas ou três etapas sobrepostas até 600 ºC, com formação dos respectivos óxidos, Al2O3, Ga2O3, In2O3, e Sc2O3. / Abstract: In the present work, the aluminum, gallium, indium and scandium 2-chlorobenzylidenepyruvates were synthesized by mixing an aqueous solution of the ligand with aqueous solutions of the corresponding metal nitrate, until total precipitation. The precipitates were washed with distilled water, filtered, dried and kept in a desiccator over anhydrous calcium chloride. Elemental analysis, infrared spectroscopy, X-ray powder diffratometry, simultaneous thermogravimetry-differential thermal analysis (TG-DTA) have been used to characterize to verify the thermal stability and to study the thermal decomposition of the synthesized compounds. Infrared spectra, permitted to suggest that the coordination of the ligand to metallic ions occurs by the carboxylate anion as the unidentate form, and also as bridge without the participation of the ketonic carbonyl group. The X-ray powder diffraction patterns showed that all the synthesized compounds were obtained in the amorphous state. From the analytical and thermoanalytical results, the general formula M(2-Cl- BP)3.nH2O can be established, were M= Al, Ga, In, Sc and n= 2; 2; 1.5; 2.5; respectively. The simultaneous TG-DTA curves of these compounds showed that the dehydration occurs in a single followed by the thermal decomposition without evidence of the formation of stable anhydrous compounds. These curves also showed that the thermal decomposition occurs through two or three overlapping steps up to 600 °C with formation of the oxides Al2O3, Ga2O3, In2O3, and Sc2O3, respectively.
7

Preparação e estudo termoanalítico dos 2-clorobenzalpiruvatos de alumínio, de gálio, de índio e de escândio no estado sólido

Bannach, Gilbert [UNESP] 24 January 2003 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:30:23Z (GMT). No. of bitstreams: 0 Previous issue date: 2003-01-24Bitstream added on 2014-06-13T19:19:07Z : No. of bitstreams: 1 bannach_g_me_araiq.pdf: 590735 bytes, checksum: f83bfea808c56ac0e6f430da2cbe1887 (MD5) / No presente trabalho, os 2-clorobenzalpiruvatos de alumínio, gálio, índio e escândio foram sintetizados, misturando-se soluções aquosas do ligante com as dos respectivos nitratos até total precipitação dos íons metálicos. Os precipitados foram lavados com água destilada até total eliminação dos íons nitratos, filtrados, secos e mantidos em dessecador sob cloreto de cálcio anidro. Na caracterização, verificação da estabilidade e o estudo da decomposição térmica desses compostos foram utilizados as técnicas de análise elementar, espectroscopia de absorção na região do infravermelho, difratometria de raios X pelo método do pó e termogravimetria-analise térmica diferencial simultânea (TG-DTA). Os espectros de absorção na região do infravermelho permitiram sugerir que a coordenação do ligante aos íons metálicos ocorre pelo carboxilato de forma unidentada, formando também ligações em ponte e sem a participação da carbonila cetônica. Os difratogramas de raios X pelo método do pó mostram que todas os compostos sintetizados foram obtidos no estado não cristalino. Os resultados analíticos e termoanalíticos permitiram estabelecer a formula geral M(2-Cl-BP)3.nH2O, onde M= Al, Ga, In, Sc e n= 2; 2; 1,5; 2,5; respectivamente. As curvas TG-DTA simultâneas desses compostos mostram que a desidratação ocorre em uma única etapa, seguida da decomposição térmica sem evidência de formação de compostos anidros estáveis. Essas curvas também mostram que a decomposição térmica ocorre através de duas ou três etapas sobrepostas até 600 ºC, com formação dos respectivos óxidos, Al2O3, Ga2O3, In2O3, e Sc2O3. / In the present work, the aluminum, gallium, indium and scandium 2-chlorobenzylidenepyruvates were synthesized by mixing an aqueous solution of the ligand with aqueous solutions of the corresponding metal nitrate, until total precipitation. The precipitates were washed with distilled water, filtered, dried and kept in a desiccator over anhydrous calcium chloride. Elemental analysis, infrared spectroscopy, X-ray powder diffratometry, simultaneous thermogravimetry-differential thermal analysis (TG-DTA) have been used to characterize to verify the thermal stability and to study the thermal decomposition of the synthesized compounds. Infrared spectra, permitted to suggest that the coordination of the ligand to metallic ions occurs by the carboxylate anion as the unidentate form, and also as bridge without the participation of the ketonic carbonyl group. The X-ray powder diffraction patterns showed that all the synthesized compounds were obtained in the amorphous state. From the analytical and thermoanalytical results, the general formula M(2-Cl- BP)3.nH2O can be established, were M= Al, Ga, In, Sc and n= 2; 2; 1.5; 2.5; respectively. The simultaneous TG-DTA curves of these compounds showed that the dehydration occurs in a single followed by the thermal decomposition without evidence of the formation of stable anhydrous compounds. These curves also showed that the thermal decomposition occurs through two or three overlapping steps up to 600 °C with formation of the oxides Al2O3, Ga2O3, In2O3, and Sc2O3, respectively.
8

Exchange coupling at cobalt/nickel oxide interfaces

Baruth, Andrew Gerald. January 2009 (has links)
Thesis (Ph.D.)--University of Nebraska-Lincoln, 2009. / Title from title screen (site viewed June 26, 2009). PDF text: xxvii, 209 p. : ill. (some col.) ; 17 Mb. UMI publication number: AAT 3350440. Includes bibliographical references. Also available in microfilm and microfiche formats.
9

Developement of cycloisomerization reactions for the synthesis of nitrogen or oxygen containing heterocycles / Developement of cycloisomerization reactions for the synthesis of nitrogen or oxygen containing heterocycles

Spina, Rosella 15 December 2011 (has links)
La catalyse, les solvants alternatifs et l'économie d'atome font partie des clés pour le développement de nouvelles stratégies durables de synthèse. Des hétérocycles comme les quinoléines substituées, par réaction de cycloisomérisation catalysée par le cuivre en utilisant les liquides ioniques, et les isoquinoléines carbonylées par réaction de carbonylation oxydante catalysée par le palladium dans le méthanol ont été synthétisées. La formation sélective de 1,3-dihydroisobenzofuranes et/ou 1H-isochromènes a été tentée par réaction de cycloisomérisation catalysée par différent métaux de transition. La synthèse d'hétérocycles à cinq chaînons, par exemple furanes, pyrroles et pyrrolin-4-ones à été mise au point par nouvelle réaction de cycloisomérisation catalysée par de sels de platine ou d'or en utilisant des diols, des amino alcools ou des α-amino-ynones dans le PEG sous activation micro-ondes. Les produits sont récupérés pur après une simple étape de précipitation-filtration. Les α-amino-ynones chiral sont synthétisée à partir de N-protégé carboxyanhydrides des aminoacides (UNCAs). Une réaction de iodocyclisation a été aussi développée pour obtenir de nouvelles structures hétérocycliques. / Catalysis, alternative solvents and atom economy represent key areas for the sustainable development of versatile strategies in organic chemistry. Fused heterocycles, such as substituted quinolines by a cycloisomerization reaction using a recyclable catalytic system copper/ionic liquids and isoquinoline-4-carboxylic esters based on PdI2-catalyzed oxidative carbonylation were prepared. A selective 5-exo-dig or 6-endo-dig cyclization route to obtain 1,3-dihydroisobenzofurans and/or 1H-isochromenes was tested by metal transition cycloisomerization reaction of alkynylbenzyl alcohols in PEG. Five membered ring heterocycles such as furans, pyrroles and pyrrolin-4-ones were successfully obtained by a novel platinum or gold-catalyzed cycloisomerization reaction of diols, aminoalcohols or α-amino-ynones in poly(ethylene glycol) (PEG) under microwave irradiation. The heterocyclic systems were recovered pure after a simple precipitation-filtration work-up. The catalytic systems were studied by using the TEM and XPS techniques. The chiral α-amino-ynone substrates were prepared by an original method starting from N-protected carboxyanhydrides of amino acids (UNCAs). Also unprecedented results are reported in the area of iodocyclization to obtain chiral iodopyrrolin-ones.

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