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 20 of 28 for “"Silylation"”.
-
Silylation as a Protecting Method During Grignard Reactions: A New Synthesis of Olivetol.
In recent years the study of the chemistry of Cannabis sativa, Cannabis indica and other varieties of plants, both foreign and domestic, more commonly known as marihuana, and its flower extract, the oil of hashish, has led to many new and unique syntheses of their respective substituents.The …
-
Producing Enantiopure Secondary Alcohols via a Silylation based Kinetic Resolution and a One-Pot Polishing Sequence
… procedure and through kinetic resolutions via silylation and desilylation. Chapter 2 highlights how we have combined a moderately selective asymmetric reaction (either a reduction or allylation) with a kinetic resolution (via acylation or silylation) to generate enantiopure compounds …
-
The Kinetic Resolution of Secondary Alcohols Through A Tandem Enantioselective Silylation and the Synthesis of Bis(Oxazolidinyl)Pyridine Metal-Organic Complexes
… of these diastereomers via enantioselective silylation. This reaction is the first example of a kinetic resolution of secondary alcohols through a tandem sequence. This work then inspired us to design a `clean-up' reaction: where an asymmetric reaction which generates modest e.e. can be …
-
The application of gas liquid chromatography to the simultaneous analysis of sugars and sugar phosphates in biological samples /|nby David J. LeBlanc. -- 260 St. Catharines [Ont. : s. n.],
… from biological samples. A new method of silylation involving dimethylsulfoxide, hexamethyldisilazane, trimethylchlorosilane and cyclohexane (1:0.2:0.1:1) which rapidly silylated sugars and sugar phosphates was developed. Subsequent chromatography on a 5% SE-52 column gave good resolution …
-
Determination of ground-water tracer 2,6-difluorobenzoic acid by Gc/Ms
… which include two methylation methods and one silylation method, have been evaluated. Chromatographic instruments including GC/MS, GC/ECD, and GC/FID have been used. Silylation of 2,6-DFBA combined with GC/MS analysis has proven to be the best method in this study, due to the low detection …
-
Derivation and chromatographic separation of acid indole auxins
For many years silylation of polar and thermolabile compounds has been used to facilitate their gas chromatographic analysis. The three phytochemically significant indole acids; 3-indole acetic acid, 3-indole propionic acid, and 3-indole butyric acid along with an analog, D-tryptophan, are four …
-
Interfacial Interactions in Polyaniline Containing Hybrids
… developed via a new facile one-pot and one-step silylation method with an aniline functionalised coupling agent, namely 3- phenylaminopropyltrimethoxysilane (PAPTMOS). The products of silylation were applied to prepare the PANI containing hybrids which were mostly electrically conductive due to …
-
Synthesis and Structure Assignments of Novel Azolinone Ribonucleosides
… of a series of azolinones was achieved via silylation and SnCl(,4) catalysis. Ribosidation of 4-imidazolin-2-one gave 1-(beta)-D-ribofuranosyl-4-imidazolin-2-one; of 1,2,4-triazolin-3-one gave 1-, 2-, and 4-(beta)-D-ribofuranosyl-1,2,4-triazolin-3-one, and …
-
Crystal morphology and surface reactivity studies of calcium hydroxide
… stability and chemical stability of the surface. Silylation was found not to occur by direct contact between the precipitated calcium hydroxide samples and silylating agents. Silylation only occurred when precipitation was carried out in the presence of a solution of the silylating agent in …
-
Hydroxyl functionalities of middle rank british coals
… were employed, three of which - stannylation, silylation and methylation - were based on in situ analysis. The fourth technique - acetylation - involved derivatisation followed by analysis of a leaving group. The four different techniques were critically compared and it is concluded that …
-
Development and applications of copper(I) hydride catalysis in asymmetric reactions and heterocycle synthesis
… are ongoing, we propose that CuH-catalyzed silylation of unsaturated acids occurs to access a uniquely effective acyl electrophilic coupling partner. Chapter 3. CuH-Catalyzed Asymmetric Reduction of [alpha],[beta]-Unsaturated Carboxylic Acids to [beta]-Chiral Aldehydes The copper hydride …
-
Halfsandwich tungsten complexes with a silanol-functionalized cyclopentadienyl ligand : synthesis and reactivity
… which was shown by H/Cl exchange, methylation, silylation or phosphine substitution. These changes evoke a small but significant influence on the silanol group. For example leads an introduced phosphine to an enhanced stability of the silanol function. A further separation of the silanol group …
-
Novel materials for membrane separation processes
… in DCC/DMAP catalysed esterifications. The silylation of cis-DHCD using TBDCS and BSA was also studied. The rate of aromatisation of cis-DHCD at room temperature was studied in order to assess its stability and 1H NMR studies were also undertaken to determine the conformations adopted by …
-
Redox-active ligand uranium complexes for approaches to multi-electron chemistry
… scission. The lessons learned from the reductive silylation of this complex redox-active ligand species has allowed for application of these principles to simple UO 22+ systems.</p>
-
Zincative Functionalization of C–H Bonds Using Lithium Amide Zincate Bases
… zincates can undergo direct electrophilic silylation and borylation without the need for any transition metal catalyst. </p><p>α-Functionalization of substituted amides and esters has been achieved by utilizing a tribasic lithium zincate for direct allylation and copper-catalyzed arylation …
-
Synthetic and analytical investigations related to vegetable oils and fats.
… In this regard, it is noted that selective silylation of glycerol does not take place, and the 1,3-disilyl derivative of glycerol (prepared indirectly) does not undergo nucleophilic substitution. However, this route does hot offer any advantage over existing routes. In connection with the …
-
An investigation into the use of ultrasound in the synthesis of fine chemicals
… via halogen rearrangements.<br/><br/>The silylation of bromothiophenes was successfully achieved using several bromothiophene substrates under quiet and sonicated conditions with various reaction times and equivalents of reagents.<br/><br/>A calorimetry study on the acoustic output of the …
-
Studies in ring D fragmentation of estrone
… approaches involved conjugate stannylation and silylation of 3-methoxyestra-1,3,5,(10), 15-tetraen-17 -one to give the 15β-trimethylstannyl and 15β-trimethylsilyl 17 -ketones respectively. The stannyl ketone was converted to the …
-
A comparison of derivatisation procedures for the detection of multiple analytes in systematic forensic toxicology
… for the first time in this study, and (c) silylation with tertiary-butyldimethylsilyl-trifluoroacetamide (MTBSTFA). Model compounds were selected for the evaluation process including a primary amine (amphetamine), a secondary amine (methamphetamine), alicyclic and aromatic hydroxy compounds …
-
Synthesis and characterization of high performance polymeric materials: poly(arylene ethers), polyamides, polyesters and liquid crystalline polyarylates
… in aqueous dimethyl sulfoxide followed by silylation with hexamethyl disilazane. Both linear and star-branched structures of PAEs were synthesized and this polymerization route allowed both random and block copolymers to be prepared. Triaryl phosphine oxide containing homo-& co-PAEs …
Page 1 of 2