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STEREOCHEMISTRY OF THE DECOMPOSITION OF 1-PYRAZOLINEUnknown Date (has links)
Source: Dissertation Abstracts International, Volume: 30-05, Section: B, page: 2082. / Thesis (Ph.D.)--The Florida State University, 1969.
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NAPHTHOYL PEROXIDESUnknown Date (has links)
Source: Dissertation Abstracts International, Volume: 30-05, Section: B, page: 2104. / Thesis (Ph.D.)--The Florida State University, 1969.
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STRUCTURE, STEREOCHEMISTRY AND PHOTOCHEMISTRY OF CERTAIN DIELS-ALDER ADDUCTS OF LEVOPIMARIC ACIDUnknown Date (has links)
Source: Dissertation Abstracts International, Volume: 30-10, Section: B, page: 4567. / Thesis (Ph.D.)--The Florida State University, 1969.
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SYNTHESIS AND METALLATION OF (POSITIVE)-R AND (NEGATIVE)-(S)-1-FLUORO-1-METHYL-2,2-DIPHENYLCYCLOPROPANEUnknown Date (has links)
Source: Dissertation Abstracts International, Volume: 30-10, Section: B, page: 4568. / Thesis (Ph.D.)--The Florida State University, 1969.
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ELECTROLYTIC REDUCTION OF ORGANIC HALIDESUnknown Date (has links)
Source: Dissertation Abstracts International, Volume: 30-12, Section: B, page: 5444. / Thesis (Ph.D.)--The Florida State University, 1969.
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A STUDY OF THE PHENOLIC OXIDATIVE COUPLING REACTION IN THE SYNTHESIS OF MORPHINE ALKALOIDSUnknown Date (has links)
p-Vinyl phenyl containing alkaloid derivatives were copolymerized with divinylbenzene and the resulting insoluble macroporous polymers were treated with LiAlH(,4) to remove the accessible portion of the template alkaloids. N-Norreticuline was incorporated into the template cavities via a carbamate linkage. This polymer-bound N-norreticuline was treated with VOCl(,3) and upon removal of the product only isoboldine was isolated. / Oxidation of 3-oxoreticuline with phenyliodosodiacetate in the presence of trifluoroacetic acid gave 16-oxosalutaridine, 16-oxopallidine, 5-oxoisoboldine, and 6-oxothalidine in yields of 27%, 8%, 6%, and 10% respectively. Oxidation of 3-oxoreticuline with VOCl(,3) gave 16-oxopallidine, 5-oxoisoboldine, and 6-oxothalidine in 26%, 11%, and 9% yields respectively. Reduction of 16-oxosalutaridine with LiAlH(,4) gave salutaridinol, which was converted to ((+OR-))-thebaine upon treatment with dimethylformamide dineopentyl acetal. Since both salutaridinol and thebaine have been converted to codeine and morphine this work constitutes a formal total synthesis of these compounds. / Source: Dissertation Abstracts International, Volume: 45-11, Section: B, page: 3512. / Thesis (Ph.D.)--The Florida State University, 1984.
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A diene sector ruleDuraisamy, Muthusamy Unknown Date (has links)
Cotton effects in circular dichroism and optical rotatory dispersion spectra of 1,3-dienes and (alpha),(beta)-unsaturated ketones, for their (pi)-(pi)* transitions, are believed to arise from inherent dissymmetry of the chromophores as well as dissymmetric substituents. A selected number of chiral acyclic 1,3-dienes and (alpha),(beta)-unsaturatedaldehydes of the general structure shown were synthesized by routes thatwould also provide their absolute configurations. The chromophores in these molecules are believed to be transoidal and planar. Ultra violet and circular dichroism spectra were measured for these molecules and their longest wavelength (pi)-(pi)* Cotton effects interpreted in terms of contributions of dissymmetric substituents. A "Diene Sector Rule" has been proposed for chiral acyclic planar transoidal 1,3-dienes for their longest wavelength (pi)-(pi)* transition which would predict the absolute configurations of these molecules from their observed Cotton effects. The rule takes into account the chiral axes of the double bonds by placing the chromophore in a plane (A) and then drawing two parallel planes (B) and (C) perpendicular to plane (A) and passing through the individual double bonds. This leads to the formation of six sectors. Positive and negative signs have been assigned to each sector based on a chiral planar 1,3-diene of known absolute configuration and its observed Cotton effect assuming that a carbon-hydrogen bond makes a greater contribution to the Cotton effect than a carbon-carbon bond. The proposed rule is also applicable to chiral planar transoidal (alpha),(beta)-unsaturated aldehydes for their long wavelength (pi)-(pi)* transition. The rule was found valid for all the dienes and (alpha),(beta)-unsaturated aldehydes of known absolute configurations prepared for this study. The rule was also found applicable to natural and synthetic products containing a transoidal planar or nearly planar 1,3-diene or (alpha),(beta)-unsaturated ketone chromophore. / Source: Dissertation Abstracts International, Volume: 42-01, Section: B, page: 0211. / Thesis (Ph.D.)--The Florida State University, 1981.
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THE CHEMISTRY OF METALLOALDIMINESUnknown Date (has links)
Metalloaldimines are acyl anion equivalents derived from isonitriles and organometallic reagents. Significant advances have been achieved in the use of lithium aldimines as synthetic intermediates. Lithium aldimines couple with aryl, vinyl, and acetylenic halides. These coupling reactions are unparalleled by other acyl anion equivalents. Lithium aldimines are added to enolizable aldehydes by using an inverse addition technique. In that reaction with aldehydes, the (alpha)-hydroxyimine products undergo a novel tautomerization to give exclusively (alpha)-amino ketones. The major disadvantage of lithium aldimines as synthetic intermediates is their high basicity. / Non-alkali metalloaldimines, such as magnesium, copper, aluminum and cadmium aldimines, are uncharacteristically stable toward electrophiles. ('13)C NMR spectroscopy studies show that magnesium aldimines have no effective charge on the aldimine carbon. This data supports a dimeric structure for the non-alkali metalloaldimines which accounts for the absence of an effective charge on the aldimine carbon and thus for their unreactivity. / Certain aryl imines prepared from lithium aldimines and aryl halides display unusual NMR spectra. These spectra indicate that these imines have a very slow carbon-nitrogen single bond rotation resulting in slow chemical exchange. This process allows the observation of magnetically nonequivalent conformers in the NMR spectra. / Source: Dissertation Abstracts International, Volume: 42-06, Section: B, page: 2378. / Thesis (Ph.D.)--The Florida State University, 1981.
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DIENE-INDUCED PHOTODECHLORINATION OF 9,10-DICHLOROANTHRACENE AND FORMATION AND PHOTOCLEAVAGE OF THE 9,10-DICHLOROANTHRACENE / 1,3-CYCLOHEXADIENE PHOTOCYCLOADDUCTSUnknown Date (has links)
Photochemical formation of 9-chloroanthracene (MCA) from mixtures of 9,10-dichloroanthracene (DCA) and 2,5-dimethyl-2,4-hexadiene (DMH) in acetonitrile has been investigated using kinetic, deuterium labeling, and quenching techniques. Product studies are described which show that DCA is quantitatively converted to MCA when irradiated at 404 nm in degassed acetonitrile in the pressence of DMH. In the absence of DMH, DCA is photostable in acetonitrile. Photoformation of MCA in the DCA/DMH system is strongly inhibited by the presence of low concentrations of molecular oxygen or 1,2,4,5-tetracyanobenzene. Results from quenching studies, along with kinetic parameters given by the DMH concentration dependence of DCA disappearance and MCA appearance quantum yields implicate participation of the DCA-DMH singlet exciplex, DCA-2DMH singlet triplex, and DCA anion radical as intermediates in the photodechlorination reaction. Results from experiments employing deuterated DMH, deuterated acetonitrile, and acetonitrile containing D(,2)O or H(,2)O show that attachment of the 10-hydrogen of MCA occurs by (DCA) anion radical protonation, a finding which is discordant with free-radical mechanisms generally postulated for the quencher-induced photodehalogenation of haloaromatics. / The mechanism for the photocycloaddition of DCA to 1,3- cyclohexadiene (CHD) was investigated by spectroscopic and photochemical methods. Cycloadducts corresponding to {4(pi) + 4(pi)} addition of CHD across the 9,10- and 1,4-positions of DCA, and {2(pi) + 2(pi)} addition of CHD across DCA's 1,2-positions are the major products formed when DCA is irradiated in polar and nonpolar solvents in the presence of CHD. Chemical and physical evidence is presented which demonstrates that the DCA-CHD cycloadducts arise from chemical interactions in the singlet manifold, and indirect evidence is presented which suggestsinvolvement of a reversibly formed DCA-CHD singlet exciplex inthe photoaddition process. Findings which modify a previousdescription of photocycloaddition in the DCA/CHD system arereported. Investigation of the photophysical and photochemicalproperties of the 1,2-adduct and 9,10-adduct from the DCA/CHD / system has revealed an adiabatic photoreaction channel which converts adducts to CHD and singlet electronically-excited DCA. Quantum yields for adiabatic formation of ('1)DCA* from direct excitation of 1,2-adduct and 9,10-adduct in degassed acetonitrile (25.0(DEGREES)C) are / (DIAGRAM, TABLE OR GRAPHIC OMITTED...PLEASE SEE DAI) / respectively. Similar / (DIAGRAM, TABLE OR GRAPHIC OMITTED...PLEASE SEE DAI) / values are also obtained from 1,2- and 9,10-adduct in nonpolar solvents. / Source: Dissertation Abstracts International, Volume: 42-06, Section: B, page: 2382. / Thesis (Ph.D.)--The Florida State University, 1981.
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BIOGENETICALLY PATTERNED STEREOSELECTIVE SYNTHESIS OF EUDESMOLS VIA NITRONE-OLEFIN CYCLOADDITIONSUnknown Date (has links)
((+OR-))-(alpha)-Eudesmol (1)* was synthesized in eleven steps from methyl farnesate (2) via the intramolecular 1,3-dipolar cycloaddition of E-monocyclofarnesal nitrone (3). The cycloaddition of this nitrone afforded two isoxazolidines 4 and 5 which differed only in their stereochemistry at C-2. The isomer distribution of the cycloaddition was controlled by the temperature at which the reaction was conducted; the ratio of 4 to 5 was 4:1 at 90(DEGREES) while the proportion of 5 increased at higher temperature. The transformation of 4 to 1 was accomplished stereospecifically by a four step reductive deamination sequence. Quaternization of 4 to 6 and ring expansion of 6 afforded tetrahydro-1,3-oxazine 7. Quaternization of 7 afforded methiodide 8 which underwent C-N bond cleavage by the hydrogenolysis to give 1. / The double bond isomer ((+OR-))-(beta)-eudesmol (8) was obtained when water was present in the quaternization reaction mixture of 7. This double bond isomerization was apparently initiated by a reversible deprotonation of the C-8 methyl group by the equatorial nitrogen on C-1. Alkylation rather than protonation of the allylic anion intermediate at C-7 resulted in 7-methyl-(beta)-eudesmol (9). / The synthesis of the three isomers of (alpha)-eudesmol as well as epi-(beta)- eudesmol (10) were realized from this approach. Epi-(alpha)-eudesmol(11) and the epi-(beta)- isomer 10 were obtained by the same reactionsequences from 5. The cycloaddition of Z-monocyclofarnesalnitrone (12) resulted in the formation of isoxazolidines 13 and 14which were each then converted to the respective eudesmol, epi- / cis-(alpha)-eudesmol (15) and cis-(alpha)-eudesmol (16). / *See abstract accompanying dissertation for the structures of the numbered compounds. / Source: Dissertation Abstracts International, Volume: 42-11, Section: B, page: 4433. / Thesis (Ph.D.)--The Florida State University, 1981.
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