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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.
21

Intermediates for Paracyclophane Synthesis

Lin, Ying-tsung 08 1900 (has links)
It is proposed in this thesis that the imperfect systems of Cram and of Schubert be combined with some modifications.
22

Laser spectroscopy of putative dyes for photodynamic therapy

Quick, William Joseph January 1997 (has links)
No description available.
23

The chemistry of selected carbene and radical ion intermediates

Pugh, James K. 10 November 1998 (has links)
Graduation date: 1999
24

The formation of methylene intermediates from organic sulfur compounds

Porter, John Jefferson 08 1900 (has links)
No description available.
25

Studies in dielectric polarization I. Some organic solids. II. The polymethylene bromides.

Kamerling, Samuel Edward, January 1933 (has links)
Thesis (Ph. D.)--Princeton University, 1932.
26

Studies of carbene-solvent interactions

Tippmann, Eric M., January 2003 (has links)
Thesis (Ph. D.)--Ohio State University, 2003. / Title from first page of PDF file. Document formatted into pages; contains xxviii, 310 p.; also includes graphics (some col.) Includes bibliographical references (p. 181-183). Available online via OhioLINK's ETD Center
27

Studies in dielectric polarization I. Some organic solids. II. The polymethylene bromides.

Kamerling, Samuel Edward, January 1933 (has links)
Thesis (Ph. D.)--Princeton University, 1932.
28

Aromatic carbene transition metal complexes

Allison, Neil T. January 1978 (has links)
Thesis--University of Florida. / Description based on print version record. Typescript. Vita. Includes bibliographical references (leaves 79-81).
29

A study of methylene and its homologs and the isolation and characterization of some thiyl free radicals

Michaelsen, John Daniel, January 1955 (has links)
Thesis--Catholic University of America.
30

Synthesis of chromium carbene scaffolds for use in medicinal chemistry / Synthesis of metal carbene scaffolds for use in medicinal chemistry

Rafael, Christopher Carlos Ferreira January 2014 (has links)
This study involves using methyllithium to synthesize Fischer carbene complexes as precursors for metal templated α,β-unsaturated complexes with potential as acceptors in the Baylis Hillman reaction as well as in Dötz benzannulation. Fischer carbene complexes contain low oxidation state metal centers, are electrophilic in nature and are stabilized by π-donating substituents such as alkoxy and amino groups. The increased electron withdrawing nature of the metal carbonyl moiety was expected to improve the rates of reaction compared to organic carbonyls. Four Fischer carbenes were synthesized via nucleophilic addition of MeLi to chromium and tungsten hexacarbonyl at low temperatures followed by alkylation using either a Meerwein salt (Me₃OBF₄) to give the desired Fischer metal methyl methoxy carbenes or Et₄NBr/alkylhalide to make the corresponding ethoxy and allyloxy carbenes. Characterization was by means of ¹³C NMR, ¹H NMR, and IR. In silico studies were carried out looking at the effect of substituents on the carbene bond. Synthesis of α,β-unsaturated complexes was effected via the aldol condensation route and found to be unfavorable using enolizable aldehydes, although the use of two aryl aldehydes resulted in successful preparation of two α,β-unsaturated complexes. Difficulty in the purification of these complexes hindered their full characterization. Computational studies looked at the effect of substituents on the system as well as variation of the metal from Cr to Mo and W. Synthesis of Baylis Hillman adducts using α,β-unsaturated complexes as acceptors was unsuccessful due to the ease of product oxidization. One potential product was obtained in its crude form although purification was not possible due to oxidation. Computational studies suggested that the oxygen on the ligand negatively impacts the stability of these Fischer carbene derived Baylis Hillman adducts promoting intramolecular oxidation of the metal. The α,β-unsaturated complexes and Baylis Hillman adducts were considered to be candidates to undergo Dötz benzannulation methodology. The use of the α,β-unsaturated complexes in this reaction was generally unsuccessful, both in the microwave and in conventional reflux conditions. Computational studies of these compounds were carried out to facilitate understanding of their stability and configuration.

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