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The preparation of m-alkylphenols :|bmechanisms and reactionsThorne, Chester Lawrence 18 May 1949 (has links)
Work with m-alkylphenols as precursors for curare-like drugs and bactericidal agents has created an interest in the synthesis of m-alkylphenols. Syntheses of m-alkylphenols have consisted of numerous steps resulting in the production of the m-alkylphenol in very low yield. The general methods of syntheses of o-and p-alkylphenols are not applicable to m-alkylphenols. Knoevenagel, in 1874, prepared m-cresol from 3-methylcyclohexen-2-one-1 with a very poor yield. The production of m-alkylphenols from 3-alkylcyclohexen-2-one-1's has been investigated several times since then. In this work, resorcinol was hydrogenated to form cyclohexandione-1,3, which was in turn brominated to form 2-bromocyclohexandione-1,3. The 2-bromocyclohexandione-1,3 was reacted with an alkylmagnesium bromide to form a 3-alkyl-2-bromocyclohexen-2-one-1, which on pyrolysis yielded the corresponding m-alkylphenol. This procedure was followed to prepare m-ethylphenol, m-isopropylphenol, m-(n-butyl)phenol, m-cyclohexylphenol, and m-(n-dodecyl)phenol. 3-Ethylcyclohexanone was made by reduction of 3-ethylcyclohexen-2-one-1 formed from the reaction of ethyl-magnesium bromide and cyclohexandione-1,3. m-(n-Dodecyl)phenol has never been reported in the literature of chemistry, The possibility of preparing many other unreported or unaccessible compounds by modification of the procedures considered was noted.
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A study of selected photo Fries rearrangementsLoveridge, Elwood Lloyd 01 December 1976 (has links)
The Fries rearrangement of phenyl esters is reviewed and compared to the reaction when light is the source of energy. The products are different due to different mechanism of reaction. Light energy causes either free radical or concerted reactions. The S-phenylthiol esters and anilides were studied also. Although many of the rearrangements are the same, we did not see any alkyl migration nor decarboxylation type reactions with either the sulfur or nitrogen compounds. Three papers have been published from this work: Bradshaw, J. S., Knudsen, R. D. and Loveridge, E. L., J. Org. Chem., 35, 1219 (1970); Bradshaw, J. S., Loveridge, E. L. and White, L., J. Org. Chem., 33, 4127 (1968); and Loveridge, E. L., Beck, B. R., Bradshaw, J. S., J. Ora. Chem., 36. 221. (1971).
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The preparation of m-ethylphenol and m-phenylphenol from resorcinolRobins, Ronald Kenith 08 May 1949 (has links)
The lack of a convenient method for the synthesis of m-alkylphenols has long been recognized by organic chemists. Within recent years the study of the physiological properties of these compounds and their derivatives, particularly the curare analogues, has caused much more concern to be placed upon a satisfactory method of synthesis. The problem of their synthesis offered an interesting study in synthetic organic chemistry. Both groupd, the alkyl group and the hydroxyl group of a meta-alkylated phenol, direct to the ortho and para positions. This makes it impossible to prepare the m-alkylphenols by the usual procedures employed in the synthesis of the ortho and para substituted phenols. With the idea that m-alkylphenols might best be prepared from the corresponding 3-alkylcyclohexen-2-one-1 and with the idea that the 3-alkylcyclohexen-2-one-1 might be made readily available from the reaction of the Grignard reagent upon cyclohexanedione-1,3 (dihydroresorcinol), work was commenced . . . It is hoped that this proposed synthesis will be at least in part, an answer tot he practical synthesis of m-alkylphenols long sought by organic chemists. It is believed that this method need only be investigated further to prove its general usefulness in preparing any meta-alkylated phenol.
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Studies of enzyme-catalysed reactions of phenols and related compoundsChalmers, Brian January 1970 (has links)
No description available.
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Evaluation of some factors influencing the phenol resistance of Staphylococcus aureusSmyth, Henry Field, January 1934 (has links)
Thesis (Ph. D.)--University of Pennsylvania, 1934. / Bibliography: p. 40-41.
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Evaluation of some factors influencing the phenol resistance of Staphylococcus aureusSmyth, Henry Field, January 1934 (has links)
Thesis (Ph. D.)--University of Pennsylvania, 1934. / "References": p. 40-41.
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Effects of the common pesticide methoxychlor on ovarian steroidogenesisAkgul, Yucel. January 2007 (has links)
Thesis (Ph. D.)--West Virginia University, 2007. / Title from document title page. Document formatted into pages; contains xi, 137 p. : ill. Includes abstract. Includes bibliographical references.
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Aluminum chloride-catalyzed reactions of chloretone with a variety of phenolsWheeler, Donald Dean. January 1952 (has links)
Call number: LD2668 .T4 1952 W48 / Master of Science
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Characterization of phenolics in Marion and Evergreen blackberriesSiriwoharn, Thanyaporn 12 December 2001 (has links)
Frozen Marion (Rubus sp. hyb) and Evergreen blackberries (Rubus
laciniatus) (whole berries, berries without seeds, and seeds alone) were
acetone/ chloroform extracted. Phenolics were isolated using C₁₈ cartridges
and polyamide resins, then characterized and measured by reversed-phase
HPLC/diode array spectral techniques. The Polyamide isolated fractions of
Marion berries contained four quercetin glycosides, one kaempferol
glycoside, three acylated quercetin glycosides, (-)-epicatechin, and eight
ellagic acid derivatives. Polyamide isolated fractions of Marion seeds had
several procyanidins (including (+)-catechin and (-)-epicatechin), 11
tentative ellagitannins, and eight ellagic acid derivatives. (-)-Epicatechin and
ellagic acid derivatives were the primary phenolics in blackberry fruits and
seeds. Flavonols were the major component in whole berries, while
procyanidins and ellagic acid derivatives were the primary phenolics in
seeds. No flavonols were found in seeds.
The phenolic profiles of Marion and Evergreen were qualitatively
similar. Evergreen berries contained higher level of (-)-epicatechin, ellagic
acid derivatives, and flavonols than Marion berries. Evergreen seeds were
also higher in procyanidin content than Marion seeds, while Marion seeds
were higher in ellagic acid derivatives. No ascorbic acid was found in any
extracts. The total monomeric anthocyanin content of Marion berries (225
mg of Cyanidin 3-glucoside/100g) was 1.5 times higher than that of
Evergreen berries (154 mg/100g). However, the total phenolics, total
monomeric anthocyanins, oxygen radical absorbing capacity (ORAC), and
ferric reducing antioxidant power (FRAP) values of Marion and Evergreen
berries were not statistically different at the significance level 0.05. The total
phenolics, ORAC, and FRAP values of Marion berries were 844 mg of gallic
acid equivalent (GAE)/100g, 35.5 μmole of Trolox equivalent (TE)/g, and
79.1 μmole of TE/g, respectively. The total phenolics, ORAC and FRAP
values of Evergreen berries were 822 mg of GAE/100g, 34.3 μmole of TE/g,
and 74.2 (μmole of TE/g, respectively. Over all, Marion blackberries were
higher than Evergreen blackberries with respect to phenolic content and
antioxidant capacity.
This study confirmed that blackberries contributed a significant
source of phenolic antioxidants that may have potential health effects.
Blackberry seeds, accounting for 5.0% of the weight of Marion berries and
5.6% of Evergreen berries, had very high phenolic content and antioxidant
capacity; therefore they may be a potential source for nutraceuticals and
natural antioxidants. / Graduation date: 2002
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Influence of processing and storage on the phenolic composition of apple, pear and white grape juiceSpanos, George A. 29 July 1988 (has links)
Methodology for characterization of the phenolic profile of
apple, pear and grape juice was developed. It utilized High
Performance Liquid Chromatography (HPLC) for separation of
individual phenolic compounds and Diode Array Detection for
recording the Ultra-violet (UV) spectrum of chromatographic
peaks. The high resolution achieved and the ability of recording
more than one wavelength simultaneously, allowed for
quantitation of phenolic acids (cinnamics and benzoics), flavonol
and dihydrochalcone glycosides, arbutin and hydroxymethylfurfural
(HMF) with minimum sample preparation. Quantitation of
procyanidins, however, required preliminary isolation and
analysis in a separate run. Procyanidin isolation based on
Sephadex IH-20 resulted in high recoveries and degree of
reproducibility.
The methodology was applied to study the influence of
variety, post-harvest storage, SO₂, initial high temperature short time (HTST) heat treatment, enzymatic clarification,
fining, bottling, concentration and storage on the phenolic
composition of apple, pear and grape juice. Processing with SO₂
inhibited extensive phenolic oxidation during pulping and
resulted in increased phenolic yields. Initial HIST treatment
protected phenolics extracted in the juioe from degradation
during processing. Cinnamic hydrolysis occurred during enzymatic
clarification. The hydrolytic activity was removed with fining
or bottling. There was no appcirent reduction of phenolics with
fining. Procyanidins were sensitive to the heat applied during
bottling and concentration. Storage of juice concentrates for
nine months at 25°C resulted in formation of HMF, considerable
degradation of cinnamics and dihydrochaloones and total loss of
procyanidins and flavonols.
The effect of diffusion extraction at different teirperatures
on the phenolic composition of apple juice from different
varieties was also studied. Up to a three-fold increase in
cinnamics and a five-fold increase in dihydrochalcone glycosides
were measured in diffusion extracted juice relative to juice
extracted with conventional pressing. The increase in
procyanidins and flavonols was even higher. / Graduation date: 1989
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