Vibrational, NMR spectrum and orbital analysis of 3,3',5,5'-tetrabromobisphenol A: a combined experimental and

Shanshan Qiu1, Jin Wei, Feng Pan

  • 1School of Chemical Engineering, Nanjing University of Science and Technology, Nanjing, Jiangsu 210094, PR China. ppshanshanqiu@gmail.com

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A proton M that is coupled to a proton X results in doublet signals for M. However, NMR-active nuclei can be simultaneously coupled to more than one nonequivalent nucleus. When M is coupled to a second proton A, such as in styrene oxide, each peak in the doublet is split into another doublet.
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Aromatic compounds can be identified or analyzed using proton NMR and carbon‐13 NMR. Typically, aromatic hydrogens or hydrogens directly bonded to the aromatic rings are strongly deshielded by the aromatic ring current. Therefore, they absorb in the range of 6.5–8.0 ppm in proton NMR spectra. For instance, aromatic hydrogens directly bonded to the benzene ring absorb at 7.3 ppm. However, aromatic hydrogens of larger rings absorb farther upfield or downfield than the ideal range. Consider...
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