Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 15 of 15 for “"aziridination"”.
-
Asymmetric Dihydroxylation and Aziridination of Allenes and Related Chemistry
… unit. The rhodium-catalyzed intramolecular aziridination of allenic N-sulfonyloxy carbamates has been established. Efficient ring opening of these bicyclic compounds may provide synthetic utility in organic chemistry. The intramolecular aziridination of allenic sulfamate esters was tested on …
-
The Development of Enantioselective Rhodium-Catalysed Aziridination Reactions Directed by a Chiral Cation
… have been developed in asymmetric intermolecular aziridination, there remain significant gaps in the scope of alkenes that can be accommodated with present protocols. Chapter 2 discusses the development of an enantioselective aziridination method for alkenyl alcohols, achieved through a close …
-
Borox catalysis : a new frontier in chiral Bronsted acid catalysis derived from chiral borate anions
… particular, the long-lasted problem of the alkyl aziridination has been solved by the development of the first multi-component aziridination reaction using the IMINO-BOROX catalyst. Out of the investigations regarding alkyl aziridination, a novel multi-component asymmetric [3+2] cycloaddition has …
-
New axially chiral amine organocatalysts
… nitrogen transfer reagents in the asymmetric aziridination of chalcone substrates, with enantiomeric excesses of up to 37% seen. The first example of an isolated chiral hydrazinium salt being used as a nitrogen transfer reagent for the aziridination of enones is also described. Secondly, a …
-
The Application and Evolution of Chiral Ion-Paired Rhodium(II,II) Tetracarboxylate Catalysts for Enantioselective Nitrene Transfer
… first section of research, an enantioselective aziridination of alkenyl alcohols using these catalysts is presented, which was conducted in collaboration with Dr. Alexander Fanourakis and Arthur R. Lit. This methodology displayed high enantioselectivities for a wide scope of substrates, covering …
-
New Catalysts for Asymmetric Nitrene Transfer Based on Ion-Pairing Between Sulfonated Rhodium(II,II) Tetracarboxylates and Chiral Cations: Design, Synthesis and Applications to Enantioselective Carbon-Nitrogen Bond Formation
… mediated by these catalysts: an asymmetric aziridination of alkenyl alcohols. This substrate-directed transformation was developed with Nicholas J. Hodson and Arthur R. Lit and is broad across alkene substitutions with an empirical mnemonic developed to predict substrate performance. It is …
-
The Design and Application of Ion-paired Ligands to Address Selectivity Challenges in Transition Metal Catalysed Oxygen and Nitrogen Transfer Reactions
… and rhodium-catalysed C-H amination and alkene aziridination. Chapter 2 explores the synthesis of novel ion-paired metalloporphyrins. Porphyrins are a privileged class of ligand that are challenging to render chiral. In this work, we executed the synthesis of novel porphyrin scaffolds featuring …
-
Prediction of higher selectivity catalysts by a computer driven workflow and machine learning and computational investigation of boronate esters in the Suzuki-Miyaura cross coupling
… the planned optimization of an enantioselective aziridination reaction. Although this work was unsuccessful in the optimization of the target reaction, it revealed deficiencies in our computationally-guided workflow. In Chapter three, we address the limitations revealed in chapter two using an …
-
Remote asymmetric induction in the organocatalytic azaDarzens synthesis of peptide aziridines: towards the assembly of new glycopeptide antibiotic analogues
… of an asymmetric organocatalytic aza-Darzens aziridination protocol using diazopeptides and amino acid imines as substrates. A structurally diverse range of peptide aziridines are reported in yields and diastereoselectivity of up to 99%. It is anticipated that the remote asymmetric induction …
-
Functionalization and applications of carbon nanotubes
… transfer. In Chapter 3, we explore catalytic aziridination reactions to functionalize CNTs as well as [60]fullerene and graphite. In Chapter 4, we use amine functionalized single-walled CNTs (SWCNTs) to attach receptors for gas sensing applications. We optimize the receptors and test the …
-
The Development of New Stereoselective Transformations Using Alkenyl Boronate Complexes
… Our strategy involves metal-catalyzed asymmetric aziridination of the alkenyl boronate complex, followed by stereospecific 1,2-migration and opening of the strained ring. Optimization experiments were conducted with chiral copper, rhodium, and iridium complexes with a focus on achieving good yield …
-
Organocatalytic synthesis of chiral non-racemic aziridines, labelled with 2H, 15N, 13C stable isotopes
… is reported. The fragment is synthesised via an aziridination reaction and can be used as a template to generate teicoplanin analogues, both non-labelled and labelled with stable isotopes. It is anticipated that the stable isotope incorporating methodologies described within this thesis will be …
-
Design and synthesis of components for optically active metal-organic frameworks (MOFs) and synthetic routes to diverse deuterium labelled α-diazoacetates, α-diazoacetamides, α-diazoketones, and the antibiotic azaserine
… and its employment as a catalyst in asymmetric aziridination reactions.
-
Asymmetric synthesis of benzylic and heterobenzylic amines
… gave less satisfactory results. Moreover, the aziridination protocol did not work on other aromatic imines, e.g. 3-pyridineimine and benzaldimine, which are not capable of bidentate chelation. The N-substituent could not be removed, but aziridine underwent ring-opening by attack of nitrogen, …
-
Nitrogen-Oxidants Enable Group-Transfer Reactions
… iron nitrenoids to affect substrate-limited aziridination reactions of carbon–carbon double bonds. Specifically, Chapter two documents a best-in-class method that relies on limiting quantities of electronically varied styrene substrates to furnish synthetically useful aziridines in moderate …