Fluorine magnetic resonance

Proton magnetic resonance (carbon tetrachloride) S 3.75 (singlet with fine structure) infrared (neat) cm. 2985, 2273, 1667, 1527, 1515 fluorine magnetic resonance (carbon tetrachloride) p.p.m. (CFCI3 internal standard) 142.4 (symmetrical multiplet, 2 ortho F), 153.8 (triplet with flne structure, 1 para P, J = 20 Hz), 161.7 (multiplet, 2 meta F). 

The spectral properties of pentafluorophenylcopper te-tramer are as follows infrared (Nujol) cm. 1630 medium 1391 medium 1353 medium 1275 medium 1090,1081, and 1071 strong triplet 978 strong 785 medium fluorine magnetic resonance (tetrahydrofuran with trichlorofluoromethane as internal reference) 8 (multiplicity, number of fluorines, assignment, coupling constant J in Hz.) 107.2 (20-line multiple , 2, ortho F), 153.4 (triplet of triplets, 1, para F, J= 1.3 and 20), 162.3 (17-line multiplet, 2, meta F). Absorptions at 820-900, 1100-1125, and 1290 cm.- in the infrared spectrum and at 8 3.05 in the proton magnetic resonance spectrum indicate that dioxane is still present. 

W.L. Strauss, A.S. Unis, C. Cowan, G. Dawson, S.R. Dager, Fluorine magnetic resonance spectroscopy measurement of brain fluvoxamine and fluoxetine in pediatric patients treated for pervasive developmental disorders. Am. J. Psychiatry 159 (2002) 755-760. 

W.M. Chew, M.E. Moseiey, P.A. Miiis, D. Sessier, R. Gonzaiez-Mendez, T.L. James, L. Litt, Spin-echo fluorine magnetic resonance imaging at 2 T /r wVo spatiai distribution of haiothane in the rabbit head, Magn. Reson. imaging 5 (1987) 51-56. 

N.R. Bolo, Y. Mode, J.P. Macher, Long-term sequestration of fluorinated compounds in tissues after fluvoxamine or fluoxetine treatment A fluorine magnetic resonance spectroscopy study in vivo, MAGMA 16 (2004) 268-276. 

P. Jynge, T. Skjetne, I. Gribbestad, C.H. Kleinbloesem, H.F.W. Hoogkamer, O. Antonsen, J. Krane, O.E. Bakoy, K.M. Furuheim, O.G. Nilsen, In vivo tissue pharmacokinetics by fluorine magnetic-resonance spectroscopy—a study of liver and muscle disposition of fleroxacin in humans, Clin. Pharmacol. Then 48 (1990) 481-489. 

Note 8), 69 g (75%) of trifluoroacetyl triflate (TFAT), is of 99% purity (Note 9), as determined by fluorine magnetic resonance (Note 10). 

The reactants and products show only singlets in their fluorine magnetic resonance spectra with the following chemical shifts (downfield from fluorotrichloromethane Internal standard) 8 TFA, -76.3 TfOH, -77.3 TFAT, -73.3 and -74.8 TFAA, -75.9 triflic anhydride, -72.6 ppm. 

Source Reprinted by permission from Macmillan Publishers Ltd from Boh, N. R., Hode, Y., Nedelec, j. F., et al. Brain pharmacokinetics and tissue distribution in vivo of fluvoxamine and fluoxetine by fluorine magnetic resonance spectroscopy. Neuropsychopharmacology (2000) 23, 428-438.)... 

Fio. 22. Fluorine magnetic resonance spectra of perfluoropiperidine in CClgF solution at a series of temperatures (Reeves and Wells, 1962). 

The rates of exchange of BF3 among ether and alcohol complexes has been studied as a function of temperature by proton and fluorine magnetic resonance (Rutenberg et al., 1963 Diehl, 1958). 

Metal, Metalloidal, and Non-metal Fluoroacetates.— Fluorine Magnetic Resonance Studies.I.para-Substituted P-DifluorostyTeae [thepP-difluorostyrenesp-XC,H(-CH CFs (X — NMe OMe, Me, H, F, Cl, or CN) were obtained via the CF,Cl-CO,Na-Ph,P-aldehyde route]. Reaction of Difluorocarbene with 2-Benzylidenecyclohexanones to afford Phenylfluorofurans (CF2 generated via thermal decomposition of CF CI-COjNa). Cyclodecapentaene Derivatives (reaction of CF, from CFjCI-COjNa with 1,4,5,8-tetrahydronaphthalenes). Action of Sodimn and Lithium Chlorodifluoroacetates on... 

Let us consider the structure of inorganic compounds which may have trigonal bipyramid geometry, such as phosphorous penta-fluoride. The structure of PFs is such that two fluorine atoms are at the apical positions, while three are at the equatorial positions. Since the fluorine atoms are not in equivalent positions, there should be two lines in the fluorine magnetic resonance spectrum of this compound. Infrared spectroscopy could not be used to detect the difference in position of the fluorine atoms in this compound. 

Fluorine magnetic resonance spectra have been studied for this compound and it has been shown that it is possible to detect the difference in structure between the apical and equatorial positions in trigonal bipyramids [ ]. However, for phosphorous pentafluoride it was found that the difference is too small to detect. When one of the fluorine atoms is removed and an alkyl group is substituted, it is then possible to see the influence that the two positions have. 

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