Diastereoselective Synthesis
Mostrando 1-12 de 19 artigos, teses e dissertações.
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1. ONE-POT DIASTEREOSELECTIVE SYNTHESIS OF CHIRAL TRICYCLIC L-CYSTEINE AND D-PENICILLAMINE DERIVATIVES: A LABORATORY EXPERIMENT
A one-pot diastereoselective synthesis of thiazolidine-ring fused systems derived from enantiomerically pure amino acids, L-cysteine or D-penicillamine, and achiral succindialdehyde is described as an experiment to be carried out by upper-division undergraduate students in a laboratory classroom. Reactions were performed under mild conditions, the products w
Quím. Nova. Publicado em: 2020-01
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2. Synthesis of Chiral 1,3-Dienes through Ring-Closing Metathesis of Enantioenriched Enynes: Potential Precursors of Morphane Analogs
ABSTRACT A simple methodology for the synthesis of enynes by indium mediated diastereoselective allylation of aromatic N-tert-butanesulfinylimines bearing alkenyl groups at ortho-position with allyl bromide has been developed. The addition of the allyl indium intermediate to the chiral imine took place with excellent diastereoselectivity. Ruthenium-catalyzed
An. Acad. Bras. Ciênc.. Publicado em: 2018
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3. Grinding and Milling: Two Efficient Methodologies in the Solvent-Free Phosphomolybdic Acid-Catalyzed and Mechanochemical Synthesis of cis-4-Amido-N-yl-2-methyl-tetrahydroquinolines
The ball-milling process of ABB' Povarov reaction through mechano-chemical activation with phosphomolybdic acid (PMA) as heteropolyacid (HPA) catalyst, was first time explored. The developed high speed vibratory ball milling (HSVBM) green method offers simple and efficient diastereoselective synthesis of cis-2,4-disubstituted tetrahydroquinolines in good to
J. Braz. Chem. Soc.. Publicado em: 2016-12
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4. Diastereoselective synthesis of substituted 2-amino-1,3-propanediols from Morita-Baylis-Hillman adducts
Descrevemos nesse artigo uma abordagem diastereosseletiva, a partir de adutos de Morita-Baylis-Hillman (MBH), para a preparação de sistemas 2-amino-1,3-propanodióis substituídos com estereoquímica relativa anti. Estas unidades estruturais têm sido utilizadas como intermediárias para a síntese de diversas substâncias de interesse farmacológico e com
Journal of the Brazilian Chemical Society. Publicado em: 2012-02
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5. Estudo da Aplicação de Brometo de Índio(I) em Reações para Formação de Ligações Carbono-Carbono / Studies on the Application of Indium(I) Bromide in Carbon-Carbon
This PhD thesis describes our results on the application of indium(I) bromide in carbon-carbon bond forming reactions. Indium enolates, generated in situ from the reaction between indium(I) bromide and α,α-dichloroketones, react with carbonyl compounds and electron-deficient alkenes. Reactions of indium enolate with α,α-dichloroketones, i
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 01/03/2011
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6. Diastereoselective synthesis of β-piperonyl-γ-butyrolactones from morita-baylis-hillman adducts. highly efficient synthesis of (±)-yatein, (±)-podorhizol and (±)-epi-podorhizol
Descrevemos nesse trabalho um método simples e eficiente para a preparação diastereosseletiva de b-piperonil-g-butirolactonas hidroxiladas, a partir de um aduto de Morita-Baylis-Hillman. Para exemplificar a eficiência dessa abordagem descrevemos também as sínteses das lignanas biologicamente ativas, (±)-yateína, (±)-podorizol e (±)-epi-podorizol.
Journal of the Brazilian Chemical Society. Publicado em: 2010-12
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7. Síntese diastereosseletiva e estudo espectroscópico da (1R, 3R, 3R,4R)-3-[3-piridinil0-hidroximetil]-1,7,7-trimetil biciclo[2.2.1] heptan-2-ona, do regioisômero (4-piridinil e seus produtos de redução assimétrica
vii ABSTRACT We developed in this study the total synthesis of new potential ligands and / or chiral organocatalysts to be initially used in the Morita- Baylis-Hillman reaction and / or in other enantioselective reactions. The preparation of four new chiral unpublished compounds (31, 32, 33, 34) derivatives of pyridine and of R-(+)-camphor (21a) were perform
Publicado em: 2010
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8. Reação de Morita-Baylis-Hillman em quimica organica. 1-Estudos mecanisticos por espectrometria de massas. 2-Sintese de farmacos, sintese diastereosseletiva de 1,2-amino-alcoois via rearranjo de Curtius / The Morita-Baylis-Hillman reaction in organic chemistry. 1-Mechanistic studies by mass spectrometry. 2-Synthesis of drugs, diastereoselective synthesis of 1,2-aminoalcohols via Curtis rearrangement
Esse trabalho de doutorado visou explorar a reação de Morita-Baylis- Hillman (MBH) nos aspectos relacionados ao seu mecanismo e a utilização de seus adutos, como substratos para síntese de moléculas com propriedades biológicas. Realizamos estudos mecanísticos dessa reação, utilizando ESI-MS, sendo possível, interceptar e caracterizar, em fase gaso
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 21/08/2009
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9. Diastereoselective total synthesis of (±)-trans-trikentrin A / Síntese total diastereosseletiva da (±)-trans-triquentrina A
Esta tese descreve uma nova abordagem para a síntese de ciclopenta[g]indóis baseada na reação de contração de anel mediada por trinitrato de tálio (TTN) de uma olefina tricíclica, que contém uma unidade indólica. Foi possível encontrar condições reacionais em que o sal de tálio(III) mostrou-se quimiosseletivo, reagindo com a ligação dupla do
Publicado em: 2009
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10. Assinalação Estereoquímica de Produtos e Descrição de Mecanismos para Reações de Acoplamento entre α,α- Diclorocetonas e Compostos Carbonílicos Promovidas por Brometo de Índio(I) / Indium(I) Bromide-Mediated Coupling of α,α-Dichloroketones with Carbonyl Compounds: Stereochemical Assignments and Description of Reaction Mechanisms
This work describes our results on the use of indium(I) bromide in Organic Synthesis, namely the reaction mechanisms and stereochemical outcome. Indium enolates, generated from the reaction between indium(I) bromide and α,α-dichloroketones, react with carbonyl compounds. The primary coupling with aldehydes leads to the diastereoselective synthesis
Publicado em: 2007
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11. Addition of Chiral Allyltrichlorostannanes to Chiral Aldehydes : total syntheseis of (+)-Prelactone B / Adição de aliltriclorestanana quirais a aldeidos quirais : sintese total da (+)-prelactona B
The Lewis-acid mediated reaction of allylsilanes and allylstannanes with aldehydes is a well-known procedure for the preparation of homoallylic alcohols. Chiral allyltrichlorostannanes react with chiral a-methyl, b-alkoxy and syn and anti a-methyl-b-alkoxy aldehydes to give the corresponding homoallylic alcohols with moderate to high 1,4-syn-diastereoselecti
Publicado em: 2006
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12. Estudos visando a elucidação estrutural do alcaloide parviestemoamida : sintese (+/-)-10-epi- parviestemoamida
(-)-Parvistemoamide, a member of the Stemona alkaloids was reported by Xu and coworkers in 1991 as a minor alkaloid fram the roots of Stemona parviflora. Extracts of the Stemonaceae species have been used in Chinese and Japanese folk medicine as insecticides, antihelmintics for domestic animaIs and drugs for the treatment of human respiratory diseases such a
Publicado em: 2005