Ph. D. THESIS 2009
Ph. D. THESIS 2009
Ph. D. THESIS 2009
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Scheme 9<br />
This equilibrium was investigated using 1 H NMR spectra. The experiments<br />
were based on the differences of the chemical shifts for the equatorial protons<br />
at positions 2,4,6,8 belonging to the syn (4e,6e = 3.48 ppm) and to the anti<br />
isomers (2e,6e = 3.36 ppm).<br />
Figure 23. Part 1 H-NMR spectrum of a crude mixture of syn and anti isomers of<br />
dioxime 5<br />
The experiments were run starting from either the pure syn or anti<br />
isomers and were based on the recording of the 1 H NMR spectra of the same<br />
sample over several periods of time and on the measuring in these spectra of<br />
the ratios between the isomers using the intensities of their specific signals<br />
(Figures 24 and 25).<br />
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