Abstract: This procedure demonstrates the nitration of methyl benzoate to prepare methyl m-nitrobenzoate. Methyl benzoate was treated with concentrated Nitric and Sulfuric acid to yield methyl m-nitrobenzoate. The product was then isolated and recrystallized using methanol. This reaction is an example of an electrophilic aromatic substitution reaction, in which the nitro group replaces a proton of the aromatic ring. Following recrystallization, melting point and infrared were used to identify and characterize the product of the reaction.
Purpose: The purpose of this experiment is to synthesize methyl nitrobenzoate from methyl benzoate, concentrated nitric acid, and concentrated sulfuric acid via an electrophilic aromatic substitution reaction. This experiment demonstrates an electrophilic aromatic substitution.
D. L. Pavia, G. M. Lampman, G. S. Kriz, and R. G. Engel “A Microscale Approach to Organic Laboratory Techniques, 3rd Ed.” (2013) Brooks/Cole, pp. 338-342.
Methyl Benzoate: Limiting Reagent
3.05 g 1 mol MB 1 mol product 181 g product= 4.06 g product
136 g 1 mol MB1 mol product
1st Crystallization: 2.13g
2nd Crystallization: 1.84 g
Final weight of product: 1.84 g
Percent Yield: 1.84gx 100%= 45.3 %
Compound| M.W (g/mol)| M.P (°C)| B.P (°C)| Density (g/mL)| Methyl Benzoate| 136| -15| 198-200| 1.08|
Methyl nitrobenzoate| 181| 78-79| 279| |
Conc. Nitric acid| 63| -42| 120.5| 1.41|
Conc. Sulfuric acid| 98| 10| 290| 1.84|
Methanol| 32| -98| 65| 0.792|
*Physical constant values taken from: http://www.chemicalbook.com/Search_EN.aspx?keyword= Experimental Melting Point: 76 - 77 °C
The experimental melting point attained confirmed the identity of the isolated product as methyl...