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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

Environmentally friendly oxidation catalysis using supported reagents

Butterworth, Andrew J. January 1997 (has links)
No description available.
2

IT : oxidations of alkanes and alkenes by T butyl hydroperoxide or molecular oxygen catalysed by polybenzimidazole supported metal complexes

Ólason, Gunnar B. January 1997 (has links)
No description available.
3

Aspects of stereochemical control in organic synthesis

Bish, E. H. January 1985 (has links)
No description available.
4

Applications of new methods for the synthesis of #beta#-hydroxy-#alpha#-amino acids

Adams, Zoe Michelle January 1999 (has links)
No description available.
5

Synthesis of a clickable FDG precursor for PET in vivo imaging

Säberg, Alexander January 2015 (has links)
The thesis of this study describes a synthesis way to produce an alkyne equipped clickable precursor of 2-deoxy-2-fluoro-D-glucose (FDG) with a beta-configuration. This FDG-derivate is produced with a clickable link in purpose to be used in PET in vivo imaging. The product was synthesized by acetylation protection and further epoxidation on the glucose analog D-Glucal. Glycosylation occurred by electrophilic reaction of propargyl alcohol and configuration of the product was ensured during Lattrell-Dax inversion.
6

New systems for catalytic asymmetric epoxidation

Parkes, Genna Alexandria January 2007 (has links)
No description available.
7

Epoxidierung von Olefinen mit Wasserstoffperoxid : Neue katalytische Systeme auf der Basis fluorierter Alkohole /

Hüttenhain, Daniel. January 2007 (has links)
Thesis (doctoral)--Universität Köln, 2007.
8

Control of the stereochemistry of C14 hydroxyl during the total synthesis of withanolide E and physachenolide C

Anees, Muhammad, Nayak, Sanjit, Afarinkia, Kamyar, Vinader, Victoria 27 November 2018 (has links)
Yes / The stereochemical outcome of the epoxidation of Δ14–15 cholestanes with mCPBA is controlled by the steric bulk of a C17 substituent. When the C17 is in the β configuration, the epoxide is formed in the α face, whereas if the C17 is trigonal (flat) or the substituent is in the α configuration, the epoxide is formed in the β face. The presence of a hydroxyl substituent at C20 does not influence the stereochemical outcome of the epoxidation. / We thank University of Bradford for a bursary (MA).
9

The development of a general method for the asymmetric epoxidation of electron deficient alkenes

Elston, Catherine L. January 1996 (has links)
No description available.
10

Enantioselective epoxidation of simple alkenes based upon the concept of pi-interactions-facial recognition

Antequera-Garcia, Gema 20 December 2005 (has links)
The aim of our project is to build new catalysts for the asymmetric epoxidation of alkenes using ð-interactions as fundamental factors for the control of the facial selectivity. It was decided to employ cinchona alkaloid derivatives as the basic core of our catalysts. We envisage that the alkene would interact selectively with the aromatic rings of the catalyst to give the corresponding epoxide in good enantiomeric excess. Quinuclidine derived cataysts of simplified structures were synthesised to find the best conditions for the experiments using chiral cinchona derivatives. An important result to be taken into account in the development of the chiral catalysts was the influence of the counterion on the conversion rate. The triflate gave the highest epoxidation rates for trans-â-methylstyrene. The use of a mixture MeOH/ DMM/ H2O led to a two fold increase in reaction rate and is recommended to increase the van der Waals interactions between the aromatic rings of the catalyst and the alkene. New catalyst amd a new epoxidation protocol for the epoxidation of alkenes mediated by dioxiranes have been disscussed .Encouraging results have been obtained from this work.

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