Bruker AVANCE NEO - Ventilation

Introductory Theory and Terminology
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3.4 Proton Spectrum of Benzene
The structure of the benzene ring is illustrated in the following figure:
Figure3.7: Benzene Ring
All six protons (labeled H
a
) may be deemed identical. They are each single-bonded to one
carbon atom. Each carbon atom in turn forms two aromatic bonds with its nearest carbon
neighbors. Hence each of the six protons is in an identical chemical environment and is said
to be chemically equivalent, and in this case even magnetically equivalent. They will all
resonate at precisely the same frequency f
1
without showing a coupling pattern. Therefore,
for pure benzene we can expect a single signal. The figure below is a spectrum of benzene in
acetone - d6 and shows that the signal is located at 7.5 ppm.
Figure3.8: Spectrum of Benzene