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Chemistry Faculty Publications

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Articles 1111 - 1129 of 1129

Full-Text Articles in Chemistry

Some Useful Synthetic Applications Of Gold's Reagent, John T. Gupton Jan 1986

Some Useful Synthetic Applications Of Gold's Reagent, John T. Gupton

Chemistry Faculty Publications

While looking for some appropriate research projects, I had been impressed by and interested in the work of Danishefsky1 and others2 regarding the use of "Eschenmoser's salt" (1). During the course of a literature search on an industrial project, we came across an article by Gold,3 which described the preparation of a rather interesting vinylogous iminium salt (2). The name assigned to this compound was [3-(dimethylamino)-2-azaprop-2-en-1-ylidene]dimethylammonium chloride. This terminology seemed a little cumbersome for routine discussions so we adopted the name "Gold's Reagent" for compound 2. Although the reagent had been prepared3 in 1960, very little …

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Method For Direct Preparation For 1,2,4-Triazole From Hydrazine And Formamide, Harris E. Petree, Joseph R. Pociask, John T. Gupton Jan 1981

Method For Direct Preparation For 1,2,4-Triazole From Hydrazine And Formamide, Harris E. Petree, Joseph R. Pociask, John T. Gupton

Chemistry Faculty Publications

Process for the preparation of 1,2,4-triazole comprises contacting hydrazine or its aqueous solutions with at least about 2.5 moles of formamide at a temperature of 140° to 210° C. and then recovering the resultant 1,2,4- triazole in yields of 92-98% with 94-98% purity. The formamide is maintained in an excess over about the 2.5 molar amount consumed in the reaction with the hydrazine. Recovery steps for isolating the 1,2,4-triazole are disclosed.

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Studies Of The Reorientational Relaxation Of Pyridine In Water By Depolarized Rayleigh Light Scattering, Scott Whittenburg Apr 1980

Studies Of The Reorientational Relaxation Of Pyridine In Water By Depolarized Rayleigh Light Scattering, Scott Whittenburg

Chemistry Faculty Publications

The depolarized Rayleigh spectra of aqueous solutions of pyridine have been studied using a high‐finesse Fabry–Perot interferometer as a function of temperature and concentration. The Rayleigh relaxation times are found to have a complex concentration and viscosity dependence. The classical Stokes–Einstein–Debye equation for molecular reorientation breaks down in this system. The Rayleigh relaxation time of pyridine molecules is not determined by the macroscopic shear viscosity of the solution. The specific interaction due to the formation of hydrogen bonds between pyridine and water molecules plays a very important role in affecting the relaxation time. At a fixed temperature the plot of …

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Comment On "Depolarized Rayleigh Spectroscopy From Benzonitrile", Scott Whittenburg Jul 1979

Comment On "Depolarized Rayleigh Spectroscopy From Benzonitrile", Scott Whittenburg

Chemistry Faculty Publications

No abstract provided.

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Raman Scattering Study Of Cs2 In Cci4, Scott Whittenburg Mar 1979

Raman Scattering Study Of Cs2 In Cci4, Scott Whittenburg

Chemistry Faculty Publications

No abstract provided.

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Depolarized Rayleigh Scattering Study Of Pyridine In Cyclohexane, Scott Whittenburg Feb 1979

Depolarized Rayleigh Scattering Study Of Pyridine In Cyclohexane, Scott Whittenburg

Chemistry Faculty Publications

No abstract provided.

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A Process For The Production Of 2-Alkyl Or 2-Cycloalkyl-4-Methyl-6-Hydroxypyrimidines, Joseph T. Blackwell Iii, John T. Gupton, Teruko U. Miyazaki, James B. Nabors, Joseph R. Pociask Jan 1979

A Process For The Production Of 2-Alkyl Or 2-Cycloalkyl-4-Methyl-6-Hydroxypyrimidines, Joseph T. Blackwell Iii, John T. Gupton, Teruko U. Miyazaki, James B. Nabors, Joseph R. Pociask

Chemistry Faculty Publications

Production of 2-alkyl- or cycloalkyl-4-methyl-6- hydroxypyrimidines by first neutralizing an alkyl imidate ester hydrochloride with a base in the presence of a water-immiscible solvent for the alkyl imidate ester to be freed thereby; condensing the alkyl imidate ester with diketene to form an oxazinone intermediate, which is then reacted in organic solution with gaseous ammonia and recovering the desired substituted 6-hydroxypyrimidine.

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Light Scattering Studies Of Orientational Fluctuations Of Cs2, Scott Whittenburg Oct 1978

Light Scattering Studies Of Orientational Fluctuations Of Cs2, Scott Whittenburg

Chemistry Faculty Publications

We have measured the depolarized Rayleigh relaxation time of CS2 as a function of temperature and concentration in an optically isotropic solvent CCl4. The concentration dependence of the relaxation times indicates the importance of orientational pair correlation in CS2. The orientational pair correlation factor is found to depend on concentration at high CS2 concentration, as well as viscosity and temperature, in contrast to what is observed in other small molecules. The single particle reorientation times were obtained by extrapolating from the depolarized Rayleigh relaxation times to infinite dilution. These were compared with the predictions of the hydrodynamic slip and stick …

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Erratum: Light Scattering Studies Of Rotational And Vibrational Relaxations Of Acetonitrile In Carbon Tetrachloride, Scott Whittenburg Mar 1978

Erratum: Light Scattering Studies Of Rotational And Vibrational Relaxations Of Acetonitrile In Carbon Tetrachloride, Scott Whittenburg

Chemistry Faculty Publications

No abstract provided.

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Erratum: A Comparison Of The Rough Sphere Rotational Diffusion Model With Experimental Results For Liquid Methyl Iodide, Scott Whittenburg Dec 1977

Erratum: A Comparison Of The Rough Sphere Rotational Diffusion Model With Experimental Results For Liquid Methyl Iodide, Scott Whittenburg

Chemistry Faculty Publications

No abstract provided.

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Erratum: Light Scattering Studies Of Transverse Sound Wave And Molecular Motion In Benzonitrile, Scott Whittenburg Oct 1977

Erratum: Light Scattering Studies Of Transverse Sound Wave And Molecular Motion In Benzonitrile, Scott Whittenburg

Chemistry Faculty Publications

No abstract provided.

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Light Scattering Studies Of Transverse Sound Wave And Molecular Motion In Benzonitrile, Scott Whittenburg Jun 1977

Light Scattering Studies Of Transverse Sound Wave And Molecular Motion In Benzonitrile, Scott Whittenburg

Chemistry Faculty Publications

The zero-frequency shear wave dip appearing in the depolarized Rayleigh spectrum in benzonitrile has been studied as a function of concentration and temperature. The solution study was carried out at constant viscosity equal to the viscosity of liquid benzonitrile at each temperature. The result indicates that the presence of shear wave fine structure does not depend on the collective orientational fluctuations. The orientational and vibrational relaxation times of benzonitrile were measured at various concentrations and temperatures. The orientational relaxation times show no concentration dependence at any temperature, suggesting that the pair correlation is negligible at all concentrations. The orientational relaxation …

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Light Scattering Studies Of Rotational And Vibrational Relaxations Of Acetonitrile In Carbon Tetrachloride, Scott Whittenburg May 1977

Light Scattering Studies Of Rotational And Vibrational Relaxations Of Acetonitrile In Carbon Tetrachloride, Scott Whittenburg

Chemistry Faculty Publications

The rotational and vibrational relaxation times of acetonitrile-carbon tetrachloride solutions were investigated as a function of concentration. viscosity, and temperature using depolarized Rayleigh and Raman scattering. Using a Fabry-Perot interferometer and single frequency laser source, we have shown that reliable results for the single particle orientational correlation times (T,) for -CH3CN can be obtained by carrying out a concentration dependent depolarized Rayleigh scattering study. Raman scattering was shown to yield inconsistent results for T. in CH3CN. At constant viscosity, it was found that the Rayleigh scattering relaxation time (TRay) of CH3CN in CCI. does not change with CH3CN concentration, indicating …

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Process For The Production Of 2-Alkyl Or 2-Cycloalkyl-4-Methyl-6-Hydroxypyrimidines, John T. Gupton, Alex M. Jelenevsky, Teruko U. Miyazaki, Harris E. Petree Jan 1977

Process For The Production Of 2-Alkyl Or 2-Cycloalkyl-4-Methyl-6-Hydroxypyrimidines, John T. Gupton, Alex M. Jelenevsky, Teruko U. Miyazaki, Harris E. Petree

Chemistry Faculty Publications

Production of 2-alkyl or 2-cycloalkyl-4-methyl-6-hydroxy pyrimidines by first reacting diketene and lower alkanoic or cycloalkanoic acid amides in the presence of catalytic amounts of Lewis bases or Lewis or Bronsted acids, followed by treating the N-acetoacetyl (lower) alkanoic or cycloalkanoic acid amide intermediates with ammonia in the presence of acid catalysts.

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Process For The Production Of 2-Alkyl Or 2-Cycloalkyl-4-Methyl-6-Hydroxypyrimidines, J. Thomas Blackwell, John T. Gupton, Jim B. Narbors Jan 1977

Process For The Production Of 2-Alkyl Or 2-Cycloalkyl-4-Methyl-6-Hydroxypyrimidines, J. Thomas Blackwell, John T. Gupton, Jim B. Narbors

Chemistry Faculty Publications

Production of 2-alkyl or 2-cycloalkyl-4-methyl-6-hydroxy pyrimidines by sequentially reacting without isolation of any intermediates in an organic solvent (1) diketene and ammonia to produce .beta.-aminocrotonamide and (2) .beta.-aminocrotonamide, after water removal therefrom, a lower alkanoic or cycloalkanoic acid ester and an alkali metal alkoxide.

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A Comparison Of The Rough Sphere Rotational Diffusion Model With Experimental Results For Liquid Methyl Iodide, Scott Whittenburg Sep 1976

A Comparison Of The Rough Sphere Rotational Diffusion Model With Experimental Results For Liquid Methyl Iodide, Scott Whittenburg

Chemistry Faculty Publications

No abstract provided.

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Piericiden A Sensitivity, Site 1 Phosphorylation, And Reduced Nicotinamide Adenine Dinucleotide Dehydrogenase During Iron-Limited Growth Of Candida Utilis, John G. Cobley, T. P. Singer, H. Beinert, S. Grossman Jan 1975

Piericiden A Sensitivity, Site 1 Phosphorylation, And Reduced Nicotinamide Adenine Dinucleotide Dehydrogenase During Iron-Limited Growth Of Candida Utilis, John G. Cobley, T. P. Singer, H. Beinert, S. Grossman

Chemistry Faculty Publications

It has been reported that cells of Candida utilis, grown in continuous culture under iron-limited conditions, develop site 1 phosphorylation, without the appearance of piericidin sensitivity and without changes in the iron-sulfur centers of NADH dehydrogenase, on aeration in the presence of cycloheximide, as well as on increasing the supply of iron during growth. These findings were reinvestigated in the present study. The parameters and properties followed during these transitions were sensitivity of NADH oxidation to piericidin, presence or absence of coupling site 1, EPR signals appearing on reduction with NADH or dithionite, the specific activities of NADH oxidase, NADH-ferricyanide …

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Reduced Nicotinamide Adenine Dinucleotide Dehydrogenase, Piericidin Sensitivity, And Site 1 Phosphorylation In Different Growth Phases Of Candida Utilis, S. Grossman, John G. Cobley, T. P. Singer, H. Beinert Jan 1974

Reduced Nicotinamide Adenine Dinucleotide Dehydrogenase, Piericidin Sensitivity, And Site 1 Phosphorylation In Different Growth Phases Of Candida Utilis, S. Grossman, John G. Cobley, T. P. Singer, H. Beinert

Chemistry Faculty Publications

Reports in the literature indicate that during the exponential phase of growth of Candida utilis NADH oxidation is insensitive to rotenone, that rotenone sensitivity is acquired during the transition to the late stationary phase and is again lost on catabolite repression. The acquisition and loss of rotenone sensitivity appears to be accompanied by similar changes in Site 1 phosphorylation but does not appear to be reflected in the rate of oxidation of NADH (by mitochondria) or of NAD-linked substrates (by mitochondria or whole cells). In the present paper evidence is presented that these fluctuations in sensitivity to inhibitors of NADH …

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Photochemical Rearrangements Of 6/5 -Fused Cross-Conjugated Cyclohexadiensnes In Protic Solvents, Drury Caine, John T. Gupton, Ko Ming, William J. Powers Iii Jan 1973

Photochemical Rearrangements Of 6/5 -Fused Cross-Conjugated Cyclohexadiensnes In Protic Solvents, Drury Caine, John T. Gupton, Ko Ming, William J. Powers Iii

Chemistry Faculty Publications

Irradiation of the ring A unsubstituted 6/5-fused cross-conjugated cyclohexadienone (1a) and its 2-methyl derivative (1b) in methanolic acetic acid yields, in addition to other products, novel tricyclononane derivatives which have been assigned the structures (3a) and (3b).

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