Nitrating Acetanilide and Methyl Benzoate: Electrophilic Aromatic Substitution
ABSTRACT:
The electrophilic aromatic substitution reaction is the attack of a benzene ring on an electrophilic species resulting in the substitution of a proton with a functional group. The electrophilic aromatic substitution reaction nitration is used to nitrate methyl benzoate and acetanilide with a nitronium ion. Crystallization was used to purify the product. The melting point was used to determine its purity and the regiochemistry of the products. The methyl benzoate reaction product, methyl nitrobenzoate, was determined to be meta-substituted and the acetanilide reaction product, nitroacetanilide, was determined to be para-substituted.
INTRODUCTION: An electrophilic aromatic substitution reaction is the attack of an electrophile on an aromatic ring substituting for a proton. This reaction allows for the introduction of other functional groups onto the aromatic ring. The electrophile attacks the aromatic ring at the aliphatic position removing two electrons destabilizing the aromatic ring, but creating a resonance-stabilized carbocation called a sigma complex (arenium ion). Then the aliphatic proton is lost to give the substitution product. The reaction rate with the aromatic ring depends on its substituents. Groups that increase the reaction rate with benzene are called activators, while ones that decrease the reaction rate are called deactivators. Activators stabilize the arenium ion by increasing the electron density on the aromatic ring by adding two electrons via resonance or through hyperconjugation, the overlap of neighboring sigma bond with the aromatic pi system. Deactivators decrease the electron density by removing two electrons via resonance or induction, resulting in the destabilization of the arenium ion (Rowland, et al, 224).
There are three positions of electrophilic substitution on the benzene ring based on the electronic nature of the substituents (activators and deactivators). These three positions are: ortho (1,2), meta (1,3) and
The electrophilic aromatic substitution reaction is the attack of a benzene ring on an electrophilic species resulting in the substitution of a proton with a functional group. The electrophilic aromatic substitution reaction nitration is used to nitrate methyl benzoate and acetanilide with a nitronium ion. Crystallization was used to purify the product. The melting point was used to determine its purity and the regiochemistry of the products. The methyl benzoate reaction product, methyl nitrobenzoate, was determined to be meta-substituted and the acetanilide reaction product, nitroacetanilide, was determined to be para-substituted.
INTRODUCTION: An electrophilic aromatic substitution reaction is the attack of an electrophile on an aromatic ring substituting for a proton. This reaction allows for the introduction of other functional groups onto the aromatic ring. The electrophile attacks the aromatic ring at the aliphatic position removing two electrons destabilizing the aromatic ring, but creating a resonance-stabilized carbocation called a sigma complex (arenium ion). Then the aliphatic proton is lost to give the substitution product. The reaction rate with the aromatic ring depends on its substituents. Groups that increase the reaction rate with benzene are called activators, while ones that decrease the reaction rate are called deactivators. Activators stabilize the arenium ion by increasing the electron density on the aromatic ring by adding two electrons via resonance or through hyperconjugation, the overlap of neighboring sigma bond with the aromatic pi system. Deactivators decrease the electron density by removing two electrons via resonance or induction, resulting in the destabilization of the arenium ion (Rowland, et al, 224).
There are three positions of electrophilic substitution on the benzene ring based on the electronic nature of the substituents (activators and deactivators). These three positions are: ortho (1,2), meta (1,3) and