I just completed the Nitration of Methyl Benzoate in lab, as seen below:

The melting point of my product (m-3-nitrobenzoate) was 72.8 - 76.4 C while the literature melting point is 78-79 C. I am wondering what specific impurity may have caused this. The solid product was rinsed with both water and methanol and dried before taking the melting point reading.

0 OCH3 OCH3 OCH3 H H -HSO4 OH H +HQO H H CH