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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.
11

Kinetic studies of 6-halopurine nucleosides in SNAR reactions; 6-(azolyl, alkylthio and fluoro)-purine nucleosides as substrates for Suzuki reactions /

Liu, Jiangqiong, January 2007 (has links) (PDF)
Thesis (Ph. D.)--Brigham Young University. Dept. of Chemistry and Biochemistry, 2007. / Includes bibliographical references.
12

Study of nucleaphilicity of an enol tosylate fragment of [alpha]- formylglycine ([alpha]-FGly-Ots) /

Bhavaraju, Sitaram. January 2007 (has links)
Thesis (Ph.D.) -- University of Rhode Island, 2007 / Typescript. Includes bibliographical references (leaves 144-148).
13

Zum Mechanismus nucleophiler Substitutionen an bifunktionellen Benzolderivaten

Jung, Dietmar, January 1962 (has links)
Thesis (doctoral)--Ludwig-Maximilians-Universität München 1962. / Vita. Includes bibliographical references (p. 57-59).
14

Some reactions in non-nucleophilic solvents

Chalkley, G. R. January 1964 (has links)
No description available.
15

Synthesis and a Mechanistic Study of Nucleophilic Substitution in Halo-arene Chromiumtricarbonyl Complexes

Sandilands, Linda 05 1900 (has links)
<p> Arenechromiumtricarbonyl complexes have been known for many years and numerous studies of the chemistry of these molecules have been reported. The presence of the chromiumtricarbonyl unit changes the reactivity of the complexed arena, in most cases due to its strong inductive electron withdrawing effect. The resulting lowered electron density in the aromatic ring allows reactions to be carried out which would otherwise be extremely difficult if not impossible, notably nucleophilic substitution. When methoxide ion was reacted with optically pure methyl o-fluorobenzoatechromiumtricarconyl, racemization of approximately 50% was observed in the product. A brief study confirmed SN2 kinetics, but further investigation was warranted. Having eliminated the possibility of decomplexationrecornplexation, two other mechanisms were postulated -a partial decomplexation allowing the arene to roll over, or attack by methoxide at another ring position. In an effort to determine which mechanism was operating, the synthesis of a number of appropriately substituted halo-arenechromiumtricarbonyl complexes was attempted. The successful synthesis of methyl 2-chloro-5-methylbenzoatechromiumtricarbonyl wns achieved, albeit with some difficulty in in low yield, but the corresponding 2-chloro-3-methyl complex could not be made. In the case of the corresponding 2-fluoro compounds, the arenes themselves could not be made by a variety of synthetic routes, 80 synthesis of the complexes could not be attempted. The results of the reaction of methoxide ion with methyl 2-chloro-5-methylbenzoatechromiumtricarbonyl indicate that the reaction proceeds via the roll-over mechanism, although a definite conclusion cant be drawn at this time. A potentially useful synthesis of bis-(chromiumtricarbonyl)-benzo-phenones has also been developed. </p> / Thesis / Master of Science (MSc)
16

Syntéza a aplikace fluorfosfonátů / Synthesis and applications of fluorophosphonates

Cherkupally, Prabhakar January 2012 (has links)
In the Introduction part of this thesis, the chemistry of organo-fluorine compounds including the electronic properties that fluorine impacts onto organic molecules, steric effects, lipophilicity and other characteristics as well as applications and important features of organo-fluorine compounds are briefly discussed. Moreover, summary of the methods for their preparation, modern methods for fluorinations and enantioselective fluorinations, and fluoroalkylation methodologies in organic synthesis are described. Additionally, the chemistry of fluorinated phosphonates including their preparations, important applications and the chemistry of α,α-difluorophosphonates are discussed. The Results and discussion part describes nucleophilic trifluoromethylation of various electrophilic substrates using diethyl trifluoromethylphosphonate. Furthermore, efficient stereoselective synthesis of fluorovinylphosphonates by a base-induced HF elimination of α,α-difluorophosphonates is explained. In addition, synthesis of number of new, structurally diverse compounds, having a difluorophosphonate moiety using the reaction of diethyl difluoromethylphosphonate with various α,β-unsaturated carbonyl compounds, Michael acceptors and imines are reported. Also, preliminary experiments dealing with nucleophilic reactions of...
17

Upscale synthesis of symmetrical and unsymmetrical monomers towards bridge trifluoromethylated poly (p-phenylenevinylene) and theoretical NMR studies

Pinto, Jean Pierre. January 2008 (has links)
Thesis (M.S.)--Rutgers University, 2008. / "Graduate Program in Chemistry." Includes bibliographical references (p. 63-64).
18

PART I: NUCLEOPHILICITY OF CHLORIDE ION TOWARD A CARBONYL CARBON PART II: ALLYLIC PARTICIPATION IN THE SOLVOLYSIS OF ALLYL CUMYL PARA-NITROBENZOATES

Foster, James Perry, 1941- January 1968 (has links)
No description available.
19

The attachment of dyes to amino acids / by Michael John Millan.

Millan, Michael John January 1996 (has links)
Bibliography: leaves 167-176. / viii, 176 leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / This thesis aims to attach dyes to amino acids in a protein. The study examines the 1,4-addition (Michael type) of the nucleophilic groups present in a protein onto a conjugated alkyne reactive group bound to a dye moiety. The initial studies examine the reactivity of individual amino acids with nucleophilic side chains which are common in proteins towards conjugated alkynes. The second stage of the project requires the synthesis of a series of compounds such as those where a dye is attached to a conjugated alkyne via a spacer unit. The reactivity of these compounds with the individual amino acids is studied, as well as the attachment of compounds of this type to, initially, short peptides, and later to a protein such as wool. / Thesis (Ph.D.)--University of Adelaide, Dept. of Chemistry, 1997?
20

The attachment of dyes to amino acids / by Michael John Millan.

Millan, Michael John January 1996 (has links)
Bibliography: leaves 167-176. / viii, 176 leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / This thesis aims to attach dyes to amino acids in a protein. The study examines the 1,4-addition (Michael type) of the nucleophilic groups present in a protein onto a conjugated alkyne reactive group bound to a dye moiety. The initial studies examine the reactivity of individual amino acids with nucleophilic side chains which are common in proteins towards conjugated alkynes. The second stage of the project requires the synthesis of a series of compounds such as those where a dye is attached to a conjugated alkyne via a spacer unit. The reactivity of these compounds with the individual amino acids is studied, as well as the attachment of compounds of this type to, initially, short peptides, and later to a protein such as wool. / Thesis (Ph.D.)--University of Adelaide, Dept. of Chemistry, 1997?

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