Purpose: The purpose of this experiment was to synthesize methyl m-Nitrobenzoate from methyl benzoate, concentrated HNO3, and concentrated H2 SO4 by an electrophilic substitution reaction. The H2 SO4 and the HNO3 were initially combined to form nitronium ion which was then used as an electrophile in the reaction. Crystals that were collected after the formation of the methyl m-Nitrobenzoate were collected by vacuum filtration and the product was isolated and purified by recrystallization. Reaction scheme:
Formation of Electrophile:
Procedure: The procedure was as is described in “Laboratory Manual for Organic Chemistry 2311”, Eighth Edition, Jane E. Wissinger, Cengage Learning Custom Solutions, Mason, Ohio, 2010, pp. 74-76
| Methyl Benzoate| H2 SO4| HNO3| Methyl m-nitrobenzoate| Mol. Wt (g/mol)| 136.2| 98.08| 63.01| 181.0| Mass (Grams)| 0.5| -| -| 0.67| Moles(mol)| 0.0037| -| -| 0.0037| Volume (ml)| 0.5| 1.35| 0.35| -| Density (g/ml)| 1.08| 1.84| 1.51| 1.30| Melting point| -12.6oC| 10OC| -42OC| 78OC| Solubility| Insoluble| Miscible | Soluble| -| Hazards| Irritant| Highly corrosive| Toxic| -| Literature: 1Chemspider 2Merck Index
Observations and Results:
The reaction turned yellowish when the acid mixture was added to the methyl benzoate. The yellowish presence turned into white crystals when ice was added to the reaction. The crude product was obtained by vacuum filtration. It was then recrystallized to obtain the pure compound. The recrystallized mass I obtained was greater than 50%. The melting point of the purified product ranged from 72oC- 75oC. 1H NMR, TLC, and IR spectroscopy was also used to analyze...