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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.
1

Acid-catalyzed isomerization of the p-menthadienes

Salacinski, Ellen Joan, 1942- January 1966 (has links)
No description available.
2

The isomerization and stereochemistry of some iridium hydride complexes /

Yorke, William John. January 1979 (has links)
Samples of fac and mer carbonyltrihydridotris(triphenylphosphine)iridium (III) were prepared and fully characterized by i.r., ('1)H and ('31)P n.m.r. spectroscopies. Isomeric interconversion at 25(DEGREES) C was demonstrated. The rates of isomerization and hydrogen loss from each isomer were independently measured. The similarity of these rates strongly supports a mechanism by which isomerization occurs through the oxidative addition and reductive elimination of molecular hydrogen. The results of deuterium labelling experiments were consistent with the isomerization mechanism, and further suggest that either trans-oxidative addition of hydrogen or intramolecular hydride interchange in the mer isomer may occur. Various partially deuterated analogues of the fac and mer isomer were formed by further reaction in solution and identified in the ('1)H n.m.r. spectrum. An unusual downfield isotope shift occurred when deuterium is in a position trans to hydride.
3

Synthesis of 7-cis containing 3-dehydroretinal isomers and their binding properties with bovine opsin: Synthesis and properties of a series of lower homologs of β-carotene

Chen, Rongliang, Chen, Rongliang January 1995 (has links)
At head of first title: "Part 1"; at head of second title: "Part 2." / Title of second work on added title page: Preparation and properties of a series of lower homologs of β-carotene. / "December 1995." / Thesis (Ph.D.)--University of Hawaii, 1995. / Includes bibliographical references (leaves 158-167). / Typescript. / Microfiche. / 167 leaves ill. 28 cm
4

Mechanism of cis-trans photoisomerization of conjugated trienes / Cis-trans photoisomerization of conjugated trienes

Butt, Yondani Chak-Cheung January 1972 (has links)
Typescript. / Thesis (Ph. D.)--University of Hawaii at Manoa, 1972. / Bibliography: leaves 128-132. / vi, 132 l illus., tables
5

The isomerization and stereochemistry of some iridium hydride complexes /

Yorke, William John. January 1979 (has links)
No description available.
6

Reactions of hydrocarbons on oxide catalysts

Bird, Robert January 1987 (has links)
No description available.
7

Ferrocenes of Substituted Indenyl Ligands

Fern, Glen Matthew January 2005 (has links)
This thesis describes the preparation and characterization of a variety of methyl-, trimethylsilyl-, and diphenylphosphino-substituted indenes. The indenes were then used in the preparation of bis(indenyl)iron(II) complexes. The bis(indenyl)iron(II) complexes were characterized by ¹H, ¹³C, and ³¹P-NMR, UV/visible spectroscopy, cyclic voltammetry, and mass spectrometry. The cyclic voltammetry shows an approximately linear relationship between the oxidation potential and the type of substituent and its ring position, but with increasing substitution leads to lower than expected oxidation potentials. The UV/visible spectra show two absorption bands in the visible region. The position of the bands are essentially unaffected by methyl-substitution, but the low energy band red-shifts with trimethylsilyl- and diphenylphosphino-substitution. Di(2-methylindenyl)iron(II), bis(4,7-dimethyl-indenyl)iron(II), bis(1,3-bis(trimethylsilyl)indenyl)iron(II), rac-bis(1-diphenyl-phosphinoindenyl)iron(II), rac-bis(1-diphenylphosphino-3-methylindenyl)iron(II), and rac-bis(1-diphenylphosphino-2,3-dimethylindenyl)iron(II) were characterized by X-ray crystallography.The planar chiral ferrocenylphosphine bis(1-diphenylphosphinoindenyl)iron(II) is observed to undergo a facile ring-flipping isomerization from the meso isomer to the racemic isomer in THF at ambient temperature. The isomerization is slowed by the addition of the noncoordinating solvent chloroform, but is accelerated by the addition of LiCl. Rate and activation parameters for the isomerization have been determined to be: kobs = 1.6 x 10⁻⁵ s⁻¹ at 23 ℃, ΔH‡ = 58 ± 4 kJ mol⁻¹, ΔS‡ = −140 ± 15 J mol⁻¹ K⁻¹. Deuterium labeling of bis(1-diphenylphosphinoindenyl)iron(II) in the 3- and 3ʹ-position ruled out the isomerization proceeding by [1,5]-proton shifts or dissociative mechanisms. The proposed mechanism for the isomerization proceeds via coordination of two THF ligands with ring-slippage of one of the indenyl ligands until it is coordinated through the phosphine. Coordination of the indenyl ligand by the other face leads to the formation of the other isomer.The heterobimetallic complexes (bis(1-diphenylphosphinoindenyl)iron(II))-cis-dichloropalladium(II), (bis(1-diphenylphosphinoindenyl)iron(II))-cis-dichloro-platinum(II), and [(cyclooctadiene)(rac-bis(1-diphenylphosphinoindenyl)iron(II))-rhodium(I)] tetraphenylborate were prepared. Attempts to prepare dichloro(bis(1-diphenylphosphinoindenyl)iron(II))nickel(II) lead to the formation of trans-dichloro(bis(1-diphenylphosphinoindene))nickel(II). The complex (bis(1-diphenyl-phosphinoindenyl)iron(II))-cis-dichloropalladium(II) is able to catalyze the cross-coupling of bromobenzene with n-/sec-butylmagnesium chloride. However. the reaction is not selective with isomerization of the alkyl group and reduction of the halide occurring via a β-hydride elimination mechanism.
8

The study of the isomerization of trans-3-acetoxy-2-bromocyclooctene

Lewis, Virginia Hill 01 January 1972 (has links)
No description available.
9

Evaluation of the stability of microencapsulated lycopene isomers

Nagy, Mark E. January 2009 (has links)
Thesis (M.S.)--Rutgers University, 2009. / "Graduate Program in Food Science." Includes bibliographical references (p. 45-50).
10

Genetic and biochemical studies of disulfide bond isomerization in Escherichia coli

Zhan, Xiaoming. January 2002 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2002. / Vita. Includes bibliographical references. Available also from UMI Company.

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