Nitration of methyl benzoate Report
Title: Experiment 28: Nitration of Methyl Benzoate
Objective: The students will learn to nitrate methyl benzoate through electrophilic aromatic substitution reaction. They will learn the importance of regiochemistry in chemical reactions. They might experience disubstitution through a high temperature.
Reactions:
Observation:
The crystals started to form when added 2 g of crushed ice.
The addition of hot methanol dissociated the crystals.
The crystals reappeared when cooled down in the ice bath.
The IR test was performed.
Data, Analysis and Discussion:
3 ml conical vial
19.9115 g
Crushed ice 2 g
Methyl benzoate
.210 ml
Cold water
1 ml
3 ml conical vial + Methyl benzoate
20.321 g
Ice-cold methanol
.3 ml
Methyl benzoate
0.4095 g
Crude product
0.6981 g
Sulfuric acid (1st added)
.50 ml
Melting point (Literature value)
78-80 °C
Sulfuric acid (2nd added)
.15 ml
Melting point (experimental value)
72.4-733.7 °C
Nitric acid
.15 ml
Molar mass of methyl benzoate
136.15 g/mol
Molar mass of methyl m-nitrobenzoate
181.15 g/mol
Molar mass of HNO3
63.01 g/mol
Melting point (Literature value)
78-80 °C
Melting point (experimental value)
72.4-73.7 °C
Methyl benzoate is the limiting reagent
Methyl benzoate= (0.4095 g)/ (136.15 g/mol) = .0030 mol
Theoretical yield= (181.15 g/mol) x .0030 mol = 0.54345 g
Mass of crude product= 0.6981 g
% Yield = ( 0.6981 g/0.54345 g) x 100%= 128.46 %
Possible by-product:
Methyl 3,5-dinitrobenzoate: (C8H6N2O6), Average mass= 226.14 g/mol, melting pt.=107-109 °C(lit.)
theoretical yield= (226.14 g/mol) x .0030 mol= 0.67842 g
% yield =( 0.6981 g /0.67842 g) x 100% = 102.90 %
The methyl benzoate was the limiting reagent for this nitration of methyl benzoate. The experimental melting point was 4.3°C lower than the literature value. This indicated that the product was moderately impure. The experimental melting point of 72.4-73.7 °C eliminated the possibility of the
Objective: The students will learn to nitrate methyl benzoate through electrophilic aromatic substitution reaction. They will learn the importance of regiochemistry in chemical reactions. They might experience disubstitution through a high temperature.
Reactions:
Observation:
The crystals started to form when added 2 g of crushed ice.
The addition of hot methanol dissociated the crystals.
The crystals reappeared when cooled down in the ice bath.
The IR test was performed.
Data, Analysis and Discussion:
3 ml conical vial
19.9115 g
Crushed ice 2 g
Methyl benzoate
.210 ml
Cold water
1 ml
3 ml conical vial + Methyl benzoate
20.321 g
Ice-cold methanol
.3 ml
Methyl benzoate
0.4095 g
Crude product
0.6981 g
Sulfuric acid (1st added)
.50 ml
Melting point (Literature value)
78-80 °C
Sulfuric acid (2nd added)
.15 ml
Melting point (experimental value)
72.4-733.7 °C
Nitric acid
.15 ml
Molar mass of methyl benzoate
136.15 g/mol
Molar mass of methyl m-nitrobenzoate
181.15 g/mol
Molar mass of HNO3
63.01 g/mol
Melting point (Literature value)
78-80 °C
Melting point (experimental value)
72.4-73.7 °C
Methyl benzoate is the limiting reagent
Methyl benzoate= (0.4095 g)/ (136.15 g/mol) = .0030 mol
Theoretical yield= (181.15 g/mol) x .0030 mol = 0.54345 g
Mass of crude product= 0.6981 g
% Yield = ( 0.6981 g/0.54345 g) x 100%= 128.46 %
Possible by-product:
Methyl 3,5-dinitrobenzoate: (C8H6N2O6), Average mass= 226.14 g/mol, melting pt.=107-109 °C(lit.)
theoretical yield= (226.14 g/mol) x .0030 mol= 0.67842 g
% yield =( 0.6981 g /0.67842 g) x 100% = 102.90 %
The methyl benzoate was the limiting reagent for this nitration of methyl benzoate. The experimental melting point was 4.3°C lower than the literature value. This indicated that the product was moderately impure. The experimental melting point of 72.4-73.7 °C eliminated the possibility of the