B.R. Langlois, N. Roques / Journal of Fluorine Chemistry 128 (2007) 1318–1325
1325
received. TLC analyses were carried out on silica gel (Kieselgel
60F 254) deposited on aluminum plates, detection being done
by UV (254 nm). Flash-chromatographies were performed on
silica gel Geduran SI 60. Unless stated otherwise, NMR spectra
quantification was done by addition of a known quantity of this
authentic sample.
Acknowledgement
1
were recorded in CDCl3. H NMR were recorded at 200 or
300 MHz and 13C NMR spectra at 50 or 75 MHz. The
substitution pattern of the different carbons were determined by
a ‘‘DEPT 135’’ sequence. 19F NMR spectra were recorded at
188 MHz. Chemical shifts (d) are given in ppm vs. TMS (1H,
13C) or CFCl3 (19F) used as internal references. Coupling
constants are given in hertz. Crude yields were determined by
19F NMR vs. PhOCF3 (dF = ꢀ58.3 ppm) used as standard. GC
was carried out on an apparatus fitted with a semi-capillary
column (length: 15 m, diameter: 0.53 mm, film thickness
(DB1): 1 mm) and a catharometric detector. Mass spectrometry,
coupled with gas chromatography, was carried out under
electron impact at 70 eV.
The Rhodia Co., is very much acknowledged for granting N.
Roques’ Ph.D. work.
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The solvent (20 mL) and the different reagents were
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immerged in an oil bath previously brought to the desired
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´
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1
temperature. The liquid residue was analyzed by GC and H
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