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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

Chemistry of quinoline-2-carbaldehyde derivatives with malononitrile and formation of indolizines

Murali, Dheeptha 13 August 2011 (has links)
The quinoline-5,8-diones are an important class of compounds with a wide spectrum of biological activites such as antibacterial, antiasthmatic, antifungal, antitumour and antiparasitic agents. Over the past three decades many variously substituted derivatives of quinoline-5,8-diones have been synthesized and reported. The majority of them dealt with the chemistry of C-6 and/or C-7 substituted quinolinediones and were related to Lavendamycin. Our lab has developed several procedures for the condensation (Knoevenagel) and reduction of aldehydes and ketones with malononitrile. When this reductive alkylation procedure was attempted with quinoline-2-carboxaldehyde, a crude product was observed by NMR spectroscopy. This product rearranged upon attempted purification via recrystallization or column chromatography. The nucleophilic attack of the quinoline N on the C of the nitrile followed by a proton transfer and a tautomerization resulted in the creation of indolizine. We will study the reductive alkylation of a series of quinoline-5,8-diones with carboxaldehydes at the C-2 position with malononitrile. This reaction is carried out in 95% ethanol with no catalysts present. This reaction mixture is then diluted with additional 95% ethanol and then cooled in an ice/water bath before the addition of sodium borohydride (NaBH4) to afford the desired monosubstituted malononitrile. We have also carried out the reactions with a range of other substituted quinoline compounds. In these cases the indolizines were not observed. It is assumed that the indolizine product does not form due to the presence of substituents on the C-8 position. Additional studies will focus on unsubstituted C-8 quinoline rings to prepare other novel indolizines. Otherwise, various reactions are performed to force the formation of indolizine. / Introduction/background -- Preparation of quinoline derivatives and their respective carboxaldehydes -- Preparation of monosubstituted malononitriles and indolizines. / Department of Chemistry
12

Condensations by means of halogen acids ...

Pantsios, Athan Anastasov, January 1941 (has links)
Thesis (Ph. D.)--University of Chicago, 1938. / Reproduced from type-written copy. "Private edition, distributed by the University of Chicago libraries, Chicago, Illinois." eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
13

Condensation of unsaturated hydrocarbons with phenols--mechanism for the condensation of the ethylenic bond with phenols ...

Natelson, Samuel. January 1931 (has links)
Thesis (Ph. D.)--New York University, 1931. / eContent provider-neutral record in process. Description based on print version record. Bibliography: p. 13.
14

2-(2ʹ hydroxyethyl)-3-picoline and its condensation with 2-methyl-5-bromomethyl-6-aminopyrimidine hydrobromide an analog of thiamine ...

Finkelstein, Jacob, January 1939 (has links)
Thesis (Ph. D.)--Columbia University, 1939. / Vita. Bibliography: p. [22-23].
15

The condensation of open-chain glucose derivatives with derivatives of the normal form of glucose and related studies

Mitchell, Alan Thomas Smith January 1949 (has links)
The condensation of simple aliphatic and aromatic aldehydes and of ketones with cyclic and acyclic glucose derivatives has been considerably investigated and, thus, isopropylidene, ethylidene, benzal and many similar and related compounds are well known: for example, benzaldehyde condenses readily with methyl glucoside and this typical reaction may be illustrated by the equation which is formulated on the following page. It is, therefore, a continuation of this work to attempt to effect similar condensations employing, as the carbonyl component, open-chain sugar derivatives which possess a free aldehydic group and to determine whether such ‘glucosydlidene' compounds are available.
16

Condensation reaction of terephthaladehyde and acetophenone

Mitchell, Lloyd J. 01 January 1955 (has links) (PDF)
The plant pigments constitute a fascinating group of compounds whose constitution has only recently been partially clarified. Roughly speaking, there are two main groups of pigment: the plastids, associated with the protoplasmic structure of plants, and the anthocyanins, generally found in solution in the cell sap. The term “anthocyanin” is derived from the Greek, “antho” signifying flower and “cyan” meaning blue, and was introduced by the botanist Marquart in 1835 to designate the blue pigments of flowers. It has since been extended to include all of the pigments of this group, the anthocyanin pigments being responsible for the innumerable shades of blue, red, violet, mauve, and magenta that are found in nature.
17

Synthesis, degradation and practical applications of a glycerol/citric acid condensation polymer /

Trenkel-Amoroso, Jan. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2009. / Printout. Includes bibliographical references (leaves 53-54). Also available on the World Wide Web.
18

Determination and evaluation of electrical properties of metal-containing condensation polymers

Unknown Date (has links)
Doped electrically conductive polymers are one of the critical materials that have allowed the current technological revolution. Essentially all of today's applications of doped conductive polymers involve vinyl-related polymers. While the application of conductive polymers is rapidly increasing, there is need for additional materials with different electrical behaviors. The current focus is on studying condensation polymers that contain a metal atom and the possibility of undergoing entire chain delocalization of electrons. The different series of organometallic condensation polymers were synthesized by employing interfacial polycondensation technique and characterization of these products were carried out using standard techniques like light scattering photometer, fourier transform infrared spectroscopy (FTIR), matrix assisted laser desorption ionization time of flight mass spectroscopy (MALDI TOF MS) and nuclear magnetic resonance spectroscopy (NMR). The electrical measurements were carried out employing Genrad 1650-B impedance spectroscopy. Prior studies conducted in this area have led to the pathway of looking at two aspects; first, surveying 60 metal-containing polymers that can undergo entire chain delocalization studying the effect of different substituents on their electrical properties and secondly, doping selected candidates employing iodine. The products derived from 2-nitro-1,4-phenylenediamine and N-methyl-1,4- pheneylenediamines with titanocene dichloride exhibited about 10 3 to 10 5 fold magnitude increases in the electrical conductivity on doping with iodine, moving it near conductive region. This increase is dependent on the concentration of the iodine and is cyclic. The results support the starting premise that selected metal-containing condensation polymers can be doped to increase their electrical conductivity. / Further investigation is warranted to see if metal-containing condensation polymers can be important materials in the electronic industry. This research sets the stage for studying not only metal-containing polymeric materials but also to investigate the ability to increase the conductivity of other condensation polymers such as nylons and polyesters through doping. / by Amitabh J. Battin. / Thesis (Ph.D.)--Florida Atlantic University, 2009. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2009. Mode of access: World Wide Web.
19

Template-directed condensations between acyl units.

Sun, Sengen. Harrison, Paul. Unknown Date (has links)
Thesis (Ph.D.)--McMaster University (Canada), 1994. / Source: Dissertation Abstracts International, Volume: 56-08, Section: B, page: 4324. Adviser: P. Harrison.
20

The condensation of cyclohexene and succinic anhydride in the presence of aluminum chloride ...

Bernardi, Dominic Joseph, January 1941 (has links)
Thesis (Ph. D.)--University of Chicago, 1938. / Reproduced from type-written copy. "Private edition, distributed by the University of Chicago libraries, Chicago, Illinois." eContent provider-neutral record in process. Description based on print version record. Bibliographical foot-notes.

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