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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.
1311

The chemistry of a-sulfenyl trimethylsiloxy derivatives/

Kobayashi, Michio, 1952- January 1984 (has links)
No description available.
1312

The photolysis and thermolysis of some diazoamides and diazoesters /

Buu, Nguyen Thanh. January 1971 (has links)
No description available.
1313

Photolyses of cholesta-3, 5-dienes and reactions of steroidal bicyclobutanes.

Lee-Ruff, Edward January 1967 (has links)
No description available.
1314

The trimethylsilyl group in organic synthesis /

Brook, Michael Adrian. January 1983 (has links)
A general method for the formation of acetals using chlorotrimethylsilane has been developed. Dioxolanes are formed from most carbonyl groups whereas methyl acetals are only formed from electron-poor carbonyl groups. The intermediacy of a silicon-bound carbonyl species is discussed. / The method has been extended to the formation of esters. In a solution of the alcohol to be esterified, methyl, ethyl, benzyl and 2-trimethylsilylethyl esters are readily formed in the presence of chlorotrimethylsilane. Using ('29)Si-N.M.R., a trimethylsilyl ester has been shown to be an intermediate in the reaction. / The Lewis acid catalyzed condensation of 1,3-bis-trimethylsiloxy-1-methoxy-1,3-butadiene with a variety of dielectrophiles, in a 1,2 relationship, has been investigated. The relative order of electrophilic reactivity towards this compound has been found to be; RR'C(Cl)SC(,6)H(,5) > ArCOCHO > ArCOCHO > RC(OCH(,3))(,2),RC(OCH(,3))SC(,6)H(,5) > RCHCl(,2). The dialkylation of 1,3-bis-trimethylsiloxy-1-methoxy-1,3-butadiene has been shown to lead to hydroxycyclopentenones with the same substitution pattern as the prostaglandins skeleton. Using ('29)Si-N.M.R., the mechanism of this reaction has been shown to proceed in two sequential steps; reaction of the (gamma)-position takes place first to give a titanium-bound intermediate, the thus formed intermediate then undergoes (alpha)-alkylation to give the cyclopentenone compound.
1315

Cycloaromatization reactions of enamines

Kang, Guo-jun. January 1983 (has links)
Methyl 4-trimethylsilyl-3-dialkylaminocrotonate is synthesized by the silylation of methyl 3-dialkylaminocrotonate. It reacts with carbonyl electrophiles at its (gamma)-position. The unusual regiochemistry of this reaction is studied and rationalized. It reacts with enamines derived from acyclic ketones or cycloketones of large ring size (of 12 and 15 membered rings) to give aromatic compounds in a 3C + 3C combination and with enamines derived from cycloketones of 5-8 membered rings to give aromatic compounds in a 4C + 2C combination. The mechanism of this cycloaromatization reaction is investigated. / meta-Cyclophanes with a morpholino substituent are synthesized by the above cycloaromatization reaction. These meta-cyclophanes possess planar chirality and are successfully resolved. / A number of metacyclophanes with alkyl substituents at the intraannular position are synthesized. Depending on the ring size and the steric size of the alkyl group, some of them are also resolved. The rotation process of meta-cyclophane is studied through their temperature dependent ('1)H NMR.
1316

Relationship of the organoleptic to chemical methods for measuring intensity of oxidized flavor in milk fat

Lillard, Dorris Alton 28 April 1961 (has links)
Graduation date: 1961
1317

Organouranium chemistry with phosphorus ylides

Maynard, Richard B January 1979 (has links)
Photocopy of typescript. / Thesis (Ph. D.)--University of Hawaii at Manoa, 1979. / Bibliography: leaves 172-197. / Microfiche. / xii, 179 leaves ill. 29 cm
1318

The synthesis of 5, 5-dimethylbicyclo [2.1.1] hexane-1-carboxaldehyde

Ebisu, Kikuye January 1966 (has links)
Typescript. / Thesis (Ph. D.)--University of Hawaii, 1966. / Bibliography: leaves [60]-64. / x, 64 l illus
1319

Synthetic approaches toward napthazarin derivatives

Siṃha, Īśvara January 1966 (has links)
Typescript. / Thesis (Ph. D.)--University of Hawaii, 1966. / Bibliography: leaves [114]-116. / ix, 116 l illus., tables
1320

Reactions of the cobalt (II)-bipyridine system in basic aqueous solution

Conrad, Ronald Carl January 1968 (has links)
Typescript. / Thesis (Ph. D.)--University of Hawaii, 1968. / Bibliography: leaves 100-102. / viii, 102 l graphs, tables

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