Study of photolysis of 1,3-bis(4-nitrophenyl)-1-butene in acetonitrile and 2-propanol

1983 ◽  
Vol 48 (1) ◽  
pp. 279-285
Author(s):  
Gabriel Čík ◽  
Ľubomír Lapčík ◽  
Anton Blažej ◽  
Igor Šurina
Keyword(s):  
Liquid Chromatography ◽  
Reaction Mechanism ◽  
Mass Spectroscopy ◽  
Uv Spectra ◽  
Gas Liquid Chromatography ◽  
Mercury Lamp ◽  
Reaction Products ◽  
Polychromatic Radiation

Photolysis of 1,3-bis(4-nitrophenyl)-1-butene (I) in acetonitrile and 2-propanol by polychromatic radiation of a mercury lamp was studied. The photolysis kinetics was followed by UV spectra and the reaction products were analysed by IR and mass spectroscopy and by gas-liquid chromatography. The reaction mechanism in markedly affected by the presence of oxygen. Photolysis of I in acetonitrile gives mainly 4-nitrobenzaldehyde, n-heptane and toluene, in 2-propanol the principal products are stereoisomeric 1,3-diphenyl-1-butenes.

GAS–LIQUID CHROMATOGRAPHY OF TERPENES: PART II. THE DEHYDRATION PRODUCTS OF α-TERPINEOL

1961 ◽  
Vol 39 (1) ◽  
pp. 1-12 ◽  
Author(s):  
E. Von Rudloff
Keyword(s):  
Liquid Chromatography ◽  
Oxalic Acid ◽  
Complex Mixture ◽  
Reaction Times ◽  
Gas Liquid Chromatography ◽  
Minor Components ◽  
Reaction Products ◽  
The Third ◽  
Major Reaction ◽  
Trace Constituents

The complex mixture of terpenes obtained on dehydrating α-terpineol with aqueous oxalic acid was almost completely separated by gas–liquid chromatography (GLC), using rapeseed oil as a new liquid phase. Terpinolene, dipentene, α- and γ-terpinene, Δ2,4(8)-p-menthadiene, and 1,8-cineole were identified as the major reaction products; three minor and seven trace constituents were also detected. One of the minor components was p-cymene, one an oxide, and the third an unidentified hydrocarbon. The yield of these components after different reaction times was determined by GLC. The initial dehydration gives terpinolene and dipentene in the ratio of approximately 2:1. Terpinolene is isomerized to α- and γ-terpinene, Δ2,4,(8)-p-menthadiene, and the unidentified hydrocarbon, but not to dipentene. 1,8-Cineole and the other oxide are formed in a reversible reaction. Dehydration of α-terpineol with several other acidic reagents yielded mixtures of products similar to that obtained with aqueous oxalic acid. With acetic acid or acetic anhydride, however, dipentene was formed preferentially and this reaction appears to proceed via the derived acetate.

Determination of Benzaldehyde in Wines and Amyl Acetate and Isoamyl Acetate in Liqueurs by Gas-Liquid Chromatography and Confirmation by Mass Spectroscopy

1975 ◽  
Vol 58 (3) ◽  
pp. 582-584
Author(s):  
Glenn E Martin ◽  
Peter C Buscemi ◽  
Boyd B Butts
Keyword(s):  
Liquid Chromatography ◽  
Mass Spectroscopy ◽  
Isoamyl Acetate ◽  
Liquid Extraction ◽  
Amyl Acetate ◽  
Alcoholic Beverages ◽  
Gas Liquid Chromatography ◽  
Liquid Liquid Extraction ◽  
Liquid Chromatographic

Abstract Liquid-liquid extraction was carried out prior to gas-liquid chromatographic (GLC) determination of amyl and isoamyl acetate in alcoholic beverages. The concentrations of amyl acetate and isoamyl acetate ranged from 4 to 29 and 2.5 to 322 ppm, respectively. Recovery studies for isoamyl and amyl acetate were carried out; these compounds were recovered at 90 and 92%, respectively. A liquid-liquid extraction also was carried out prior to the GLC determination of benzaldehyde. When chloroform was used in the liquid extraction, the results obtained by the GLC procedure compared favorably in most cases with those obtained by the ultraviolet spectrophotometric procedure. In the GLC method the benzaldehyde varied from 5 to 150 ppm for both imported and natural wines. The compounds in the effluent from the chromatograph, namely, amyl acetate, isoamyl acetate, and benzaldehyde, were confirmed by mass spectroscopy.

Gas-Liquid Chromatography-Mass Spectroscopy Determination of Clopamide in Plasma

1989 ◽  
Vol 78 (8) ◽  
pp. 679-682 ◽  
Author(s):  
Wolfgang Stüber ◽  
Henning Blume ◽  
Fritz Sörgel ◽  
Gerd Stenzhorn
Keyword(s):  
Liquid Chromatography ◽  
Mass Spectroscopy ◽  
Gas Liquid Chromatography

Survey of 1975 Wheat and Soybeans for Aflatoxin, Zearalenone, and Ochratoxin

1977 ◽  
Vol 60 (4) ◽  
pp. 778-783
Author(s):  
Odette L Shotwell ◽  
Marion L Goulden ◽  
Glenn A Bennett ◽  
Ronald D Plattner ◽  
Clifford W Hesseltine
Keyword(s):  
North Carolina ◽  
Liquid Chromatography ◽  
Ochratoxin A ◽  
Mass Spectroscopy ◽  
Gas Liquid Chromatography ◽  
Southern Illinois

Abstract Wheat samples (102 lots) were collected from Virginia, North Carolina, southeastern Missouri, southern Illinois, and Kentucky. Soybean samples (180 lots) were collected from Virginia, Illinois, Iowa, Minnesota, Nebraska, Alabama, Arkansas, and Texas. Samples of both commodities were analyzed for zearalenone, aflatoxin, and ochratoxin by the Eppley method. None of the 3 mycotoxins was detected in soybeans. Aflatoxins and ochratoxin A were not detected in wheat, but zearalenone was detected in 19 of 42 samples collected in Virginia. Half of the Virginia samples were collected because they were mold-damaged. Zearalenone levels ranged from 0.36 to 11.05 ppm; the identity of the zearalenone was confirmed by gas-liquid chromatography and mass spectroscopy. Gibberella zea infection (6–60%) was detected in all of the zearalenone-positive samples; 6–60% of the kernels in the samples tested contained G. zea.

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