A nuclear magnetic resonance study of molecular motion in (2,4,5-Trichlorophenoxy)acetic acid

1982 ◽  
Vol 35 (11) ◽  
pp. 2367
Author(s):  
KVG Reddy ◽  
KVR Chary ◽  
BA Sastry
Keyword(s):  
Acetic Acid ◽  
Magnetic Resonance ◽  
Molecular Motion ◽  
Nuclear Magnetic Resonance Study ◽  
Temperature Range ◽  
Magnetic Resonance Data ◽  
Dimeric Unit ◽  
Resonance Data ◽  
Methylene Group ◽  
Proton Magnetic Resonance Data

Proton magnetic resonance data in polycrystalline (2,4,5-trichlorophenoxy)acetic acid in the temperature range 77-400 K are reported in this communication. After a correction is made for the H-H distance in the methylene group the rigid lattice second moment (S2) coincides with the experimental value in the temperature range 77-170 K. The observed fall in S2 in the temperature range 170- 208 K is interpreted as the result of the CH2COOH group reorientation. The barrier height associated with the reorientation is found to be 8.728 kJ mol- which indicates non-cleavage of hydrogen-bonding in the dimeric unit during reorientation.

Methods to Determine Phytopharmaceuticals in Tobacco and Tobacco Products. 4th Report: A Procedure to Determine Vamidothion and its Metabolites/Methoden zur Bestimmung von Phytopharmaka in Tabak und Tabakerzeugnissen: IV. Mitteilung: Ein Bestimmungsverfahren fuer Vamidothion und seine Metaboliten

1977 ◽  
Vol 9 (2) ◽  
Author(s):  
A.N. Sagredos ◽  
R. Moser
Keyword(s):  
Mass Spectrometry ◽  
Nuclear Magnetic Resonance ◽  
Acetic Acid ◽  
Magnetic Resonance ◽  
Aluminium Oxide ◽  
Nuclear Magnetic Resonance Data ◽  
Gas Chromatograph ◽  
Tobacco Products ◽  
Magnetic Resonance Data ◽  
Resonance Data

AbstractBased on previous work (7) a method to simultaneously determine vamidothion [I], vamidothion-sulfoxide [II] and vamidothion sulfone [III] in tobacco has been developed. The compounds are extracted with water/acetone/acetic acid from the tobacco, cleansed over an aluminium oxide column and then determined on the gas chromatograph with the specific sulphur detector. Rates of recovery are 70 % - 92 %, the determination level is 0.1 ppm. Mass spectrometry and nuclear magnetic resonance data of vamidothion [I], vamidothion-sulfoxide [ II ] and vamidothion-sulfone [III] are given.

Cycloaddition d'ylures d'azométhine dérivés de la 3,4-dihydro-6,7-diméthoxy-3-méthoxycarbonyl-isoquinoléine

1991 ◽  
Vol 69 (7) ◽  
pp. 1156-1160 ◽  
Author(s):  
Tahar Lakhlifi ◽  
Ahmed Sedqui ◽  
Bernard Laude ◽  
Nguyen Dinh An ◽  
Joël Vebrel
Keyword(s):  
Magnetic Resonance ◽  
Key Words ◽  
Proton Magnetic Resonance ◽  
Azomethine Ylide ◽  
Magnetic Resonance Data ◽  
Resonance Data ◽  
Azabicyclic Compounds ◽  
Derivatives Of ◽  
Proton Magnetic Resonance Data

Three azomethine ylide precursors including the methyl 3,4-dihydro-6,7-dimethoxyisoquinoline-3carboxylate moiety were synthesized. The 1,3-dipolar species formed from these products react with activated dipolarophilic olefines leading diastereospecifically to derivatives of 4′,5′-dimethoxy-1,2-benzo-4,7-imino-4-methoxycarbonyl-1-cycloheptene. Proton magnetic resonance data allowed the determination of the stereochemistry of the cycloadducts. Key words: cyclic azomethine ylide, azabicyclic compounds, stereochemistry.

A Comparative Proton Magnetic Resonance Study of the Molecular Conformation of Uracil and 6-Aza Uracil Nucleosides and Nucleotides

1973 ◽  
Vol 51 (15) ◽  
pp. 2571-2577 ◽  
Author(s):  
Donald J. Wood ◽  
Frank E. Hruska ◽  
Richard J. Mynott ◽  
Ramaswamy H. Sarma
Keyword(s):  
Magnetic Resonance ◽  
Proton Magnetic Resonance ◽  
Molecular Conformation ◽  
Three Dimensional ◽  
Magnetic Resonance Study ◽  
Magnetic Resonance Data ◽  
Ribose Phosphate ◽  
Resonance Data ◽  
Proton Magnetic Resonance Study ◽  
Proton Magnetic Resonance Data

Proton magnetic resonance data for uridine and uridine-5′-monophosphate, and the corresponding 6-azauracil analogs, are presented and discussed in terms of their overall three dimensional conformations in aqueous solution. The data reveal a destabilizing influence of the 6-aza base upon the gog and g′–g′ conformation of the ribose phosphate moiety.

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