Synthesis of methoxybenzoflavones and assignments of their NMR data

Doseok Hwang1, Geunhyeong Jo, Jiye Hyun

  • 1Division of Bioscience and Biotechnology, BMIC, Konkuk University, Seoul, 143-701, Korea.

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¹H NMR Signal Integration: Overview

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NMR Spectroscopy of Aromatic Compounds

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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