The number of repeating units or degree of polymerization was obtained from the [sup.1]H NMR spectra
. The conversion rate was also calculated using [sup.1]H NMR spectra
for each depolymerization reaction and applied to the diffusion ordered spectroscopy [sup.1]H NMR (DOSY-NMR) technique to determine the composition of the products.
For the [.sup.13]C NMR spectra
, multiplicities were determined using distortionless enhancement with a polarization transfer (DEPT) experiment.
Figure 1 shows the stacking of [sup.1]H NMR spectra
as obtained from the titration of L with S[O.sub.4.sup.2-] (0-10 eq.).
In their Carbon-13 NMR spectra
, the peaks due to carbonyl group was appeared around 144.23-148.08 ppm.
Likewise, the NMR spectra
generated for characterization of isorhamnetin are annexed as supporting material 7-9.
The [sup.1]H NMR spectra
were acquired using 64 K data points with a spectral width of 12019 Hz, the acquisition time of 2.73 s, the relaxation delay of 1 s, 16 scans, and a pulse width of 30[degrees].
were recorded at 500 MHz for [sup.1]H and 125MHz [sup.13]C on JNM-ECX500 system (JEOL Ltd.).
Figure 2 shows the [sup.1]H NMR spectra
of the precursor and the azo polymers with assignments.
The matrix X of dimensions z x s contains the recorded NMR spectra
as rows with the respective intensity values.
A complete assignment of [sup.1]H and [sup.13]C NMR spectra
of the hydrazones was based on analysis of NMR and 2D spectra (the HMBC correlations of 4b and 4e compounds were shown in the structures at Tables 2 and 3) and is presented in Tables 2 and 3.
[sup.13]C MAS NMR spectra
confirmed the disappearance of carbonyl groups when the precursor was heated at 400[degrees]C; this is in agreement with the results of IR analyses.
Acquisition of a console and equipment for a high field (17.6 T) nuclear magnetic resonance (NMR) spectrometer to ensure an overall improvement in the quality of NMR spectra
and measurement of advanced multidimensional NMR experiments with samples of liquid biomolecules and Solid.