SDSU Identification of Unknown Arenes by NMR Spectroscopy Lab Analysis

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Identification of Unknown Arenes by NMR Spectroscopy
Goal: Use the NMR spectra of several unknown arenes (benzene derivatives) to determine their
identity. The compounds are isomers of each other with the molecular formula, C10H14.
Lab Report
1. Title Page (This section should contain the experiment title, your name, and chemistry course
number)
2. Analysis:
•
For each unknown (A-D) draw a structure of the arene in which the hydrogens are
labeled as either Ha, Hb, Hc, etc, corresponding to the labeled peaks on the given NMR
spectrum. Note that the aromatic protons are not given letters on the spectra so you don’t
need to label the aromatic protons (Ar-H) on your drawing. Aromatic peaks can
sometimes overlap and involve complex splitting patterns that will make it harder for you
to assign them in some cases. However, the aromatic peaks may still provide useful
information by indicating whether or not there is a high degree of symmetry in the
molecule.