Ph. D. THESIS 2009

Figu re 4 . Th e 13
C-NMR APT (CDCl , 1 2 5 MHz) sp e ct r u m o f
3
co m p o u n d 2
The bridgehead tertiary carbon atoms at 1-C/5-C are located in the 13 C-
NMR APT spectrum at resonance δ= 32.64 ppm.
In conclusion, the missing of a deshielded signal pertaining to the enol
protons in 1 H NMR spectrum, as well as the presence of a highly deshielded
signal at δ= 208.59 ppm in the 13 C NMR spectrum, characteristic to the
quaternary carbonyl atom, suggests the preference for the ketone form in the
case of compound 2. Also, the conversion of 1 to 2 and the common elements
of the NMR spectra of these compound are stated to confirm the presence of
the bicyclo[3.3.1]nonane skeleton into the structure of compound 2.
1 .3 .2 . FT-IR in ve stigatio n o f tetram eth y l 3 , 7 -
d ih y d ro xy bicy clo [3 .3 .1 ] n o n a -2 , 6 -d ien e -2 , 4 , 6 , 8 -
tetracarbo xy late
One of the most suitable tools to investigate the nature of the hydrogen bonds
in the bicyclic tetraester 1 is the FT-IR spectroscopy in solution. The
experimental study consisted of the IR spectra registration in solution for
compound 1 [10] in order to investigate the behavior of substance in terms of
maintaining the hydrogen bonds and the way in which specific peaks of the
form enol changes with solvent polarity.
Theoretical spectra of conf_A and conf_B have been modeled to be compared
with experimental spectrum in order to identify which is the preferred
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