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ELECTROPHILIC NITRATION AND BROMINATION Electrophilic aromatic substitution reactions will be performed using two different electrophiles, and two aromatic substrate molecules. Benzoic acid, which has an electron-withdrawing carboxylic acid substituent, will be nitrated using mixed acid. Acetanilide, which has an electron-donating substituent, will be brominated. The resulting product(s) will be analyzed to determine the disubstituted isomers that are formed. The identity of the major products will be determined by melting point after purification by recrystallization. Prelab To prepare for this experiment, tabulate the physical properties; i.e., characteristics such as physical state, colour, melting point/boiling point/density and solubility in water and organic solvents, and any hazardous or toxic properties for all reactants and products, the amounts and moles of all reactants and the theoretical yield for the reactions. Make a flowchart for each of the procedures. Introduction The rate of an electrophilic substitution reaction on a substituted benzene ring can either be faster or slower than that of benzene, depending upon the nature of the inductive and resonance effects of the attached group. In addition, the attached group will preferentially direct an incoming substituent primarily ortho/ para or meta, depending on the nature of the attached group. Review the appropriate chapters from your textbook to ensure that you understand the reasons for the activating/deactivating, and directing effects of various groups, including the resonance structures of the intermediates formed during the course of the reaction. Liquid bromine is both difficult and dangerous to dispense, so a modified procedure in which bromine is generated in situ will be used for the bromination of acetanilide. The oxidation of bromide ion with the bromate ion will generate elemental bromine, according to the following balanced redox reaction: 6 H+ (aq) + 5 Br- (aq) + BrO3- (aq) ? 3 Br2 (aq) + 3 H2O (l) 

          ELECTROPHILIC NITRATION AND BROMINATION

Electrophilic aromatic substitution reactions will be performed using two different electrophiles, and two aromatic substrate molecules. Benzoic acid, which has an electron-withdrawing carboxylic acid substituent, will be nitrated using mixed acid. Acetanilide, which has an electron-donating substituent, will be brominated. The resulting product(s) will be analyzed to determine the disubstituted isomers that are formed. The identity of the major products will be determined by melting point after purification by recrystallization.

Prelab

To prepare for this experiment, tabulate the physical properties; i.e., characteristics such as physical state, colour, melting point/boiling point/density and solubility in water and organic solvents, and any hazardous or toxic properties for all reactants and products, the amounts and moles of all reactants and the theoretical yield for the reactions. Make a flowchart for each of the procedures.

Introduction

The rate of an electrophilic substitution reaction on a substituted benzene ring can either be faster or slower than that of benzene, depending upon the nature of the inductive and resonance effects of the attached group. In addition, the attached group will preferentially direct an incoming substituent primarily ortho/ para or meta, depending on the nature of the attached group. Review the appropriate chapters from your textbook to ensure that you understand the reasons for the activating/deactivating, and directing effects of various groups, including the resonance structures of the intermediates formed during the course of the reaction.

Liquid bromine is both difficult and dangerous to dispense, so a modified procedure in which bromine is generated in situ will be used for the bromination of acetanilide.

The oxidation of bromide ion with the bromate ion will generate elemental bromine, according to the following balanced redox reaction:

6 H+ (aq) + 5 Br- (aq) + BrO3- (aq) ? 3 Br2 (aq) + 3 H2O (l)
Show more…
ELECTROPHILIC NITRATION AND BROMINATION Electrophilic aromatic substitution reactions will be performed using two different electrophiles, and two aromatic substrate molecules. Benzoic acid, which has an electron-withdrawing carboxylic acid substituent, will be nitrated using mixed acid. Acetanilide, which has an electron-donating substituent, will be brominated. The resulting product(s) will be analyzed to determine the disubstituted isomers that are formed. The identity of the major products will be determined by melting point after purification by recrystallization. Prelab To prepare for this experiment, tabulate the physical properties; i.e., characteristics such as physical state, colour, melting point/boiling point/density and solubility in water and organic solvents, and any hazardous or toxic properties for all reactants and products, the amounts and moles of all reactants and the theoretical yield for the reactions. Make a flowchart for each of the procedures. Introduction The rate of an electrophilic substitution reaction on a substituted benzene ring can either be faster or slower than that of benzene, depending upon the nature of the inductive and resonance effects of the attached group. In addition, the attached group will preferentially direct an incoming substituent primarily ortho/ para or meta, depending on the nature of the attached group. Review the appropriate chapters from your textbook to ensure that you understand the reasons for the activating/deactivating, and directing effects of various groups, including the resonance structures of the intermediates formed during the course of the reaction. Liquid bromine is both difficult and dangerous to dispense, so a modified procedure in which bromine is generated in situ will be used for the bromination of acetanilide. The oxidation of bromide ion with the bromate ion will generate elemental bromine, according to the following balanced redox reaction: 6 H+ (aq) + 5 Br- (aq) + BrO3- (aq) ? 3 Br2 (aq) + 3 H2O (l)

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Chemistry: Structure and Properties
Chemistry: Structure and Properties
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ELECTROPHILIC NITRATION AND BROMINATION Electrophilic aromatic substitution reactions will be performed using two different electrophiles, and two aromatic substrate molecules. Benzoic acid, which has an electron-withdrawing carboxylic acid substituent, will be nitrated using mixed acid. Acetanilide, which has an electron-donating substituent, will be brominated. The resulting product(s) will be analyzed to determine the disubstituted isomers that are formed. The identity of the major products will be determined by melting point after purification by recrystallization. Prelab To prepare for this experiment, tabulate the physical properties; i.e., characteristics such as physical state, colour, melting point/boiling point/density and solubility in water and organic solvents, and any hazardous or toxic properties for all reactants and products, the amounts and moles of all reactants and the theoretical yield for the reactions. Make a flowchart for each of the procedures. Introduction The rate of an electrophilic substitution reaction on a substituted benzene ring can either be faster or slower than that of benzene, depending upon the nature of the inductive and resonance effects of the attached group. In addition, the attached group will preferentially direct an incoming substituent primarily ortho/ para or meta, depending on the nature of the attached group. Review the appropriate chapters from your textbook to ensure that you understand the reasons for the activating/deactivating, and directing effects of various groups, including the resonance structures of the intermediates formed during the course of the reaction. Liquid bromine is both difficult and dangerous to dispense, so a modified procedure in which bromine is generated in situ will be used for the bromination of acetanilide. The oxidation of bromide ion with the bromate ion will generate elemental bromine, according to the following balanced redox reaction: 6 H+ (aq) + 5 Br- (aq) + BrO3- (aq) → 3 Br2 (aq) + 3 H2O (l)
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Transcript

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00:02 Here in this question we are considering electrophilic nitration reaction which can be written as this is the reaction.
00:23 We have benzoic acid as our precursor material.
00:27 We'll be starting the reaction with this.
00:31 This is benzoic acid...
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