Question

How can you tell if the benzene ring of methyl cinnamate was reduced during the hydrogenation reaction based on nmr spectroscopy?

Answer 1

In nmr spectroscopy the aromatic hydrogens show multiplets near 7-8 δ

so if the given aromatic compound undergoes reduction, there will be reduction of aromatic ring and the peaks near the given values will not be observed making it clear that benzene ring of methyl cinnamate was reduced during the hydrogenation