Chemistry Reference
In-Depth Information
13
C-NMR spectrum of
Figure 10.6
the epoxy resonances of
the derivatized
triglyceride.
0.04
0.02
0.00
2956
2927
1748
-0.02
2874
2857
1724
-0.04
-0.06
3500
3000
2500
2000
1500
Wavenumber (cm
-1
)
Figure 10.7
Second derivative of the FT-IR spectrum of the polyformyl derivative of
milkweed oil.
the mass effect of the contribution of the many methine carbonyls compared
to the relatively fewer parent triglyceride carbonyl esters present.
A moderately weak band generally observed around 3500 cm
1
is attrib-
utable to the overtone of the very intense carbonyl absorption band at
1728 cm
1
. The
1
H-NMR spectrum of the performyl ester of milkweed oil
shows characteristic resonance frequencies of the formate methine protons
at 8.0-8.20 ppm, Figure 10.8.
Expansion of this absorption region reveals some 10 singlet resonances
(inset), whereas the
13
C-NMR spectrum of the polyformate ester shown in
Figure 10.9 has methine carbonyls of the formate ester occurring up field
around 160-161 ppm relative to the parent triglyceride ester carbonyls that
