Chapter 20, Problem 12PP

Interpretation Introduction

Interpretation:

The synthesis of $m-\text{toluidine}$ from toluene and the synthesis of $m-\text{chlorotoludine}$, $m-\text{bromotoludine}$, $m-\text{iodotoludine}$, $m-\text{tolunitrile}$, and $m-\text{toluic acid}$ are to be shown.

Concept introduction:

舧 Electrophiles are electron-deficient species, which has positive or partially positive charge. Lewis acids are electrophiles, which accept electron pair.

舧 Nucleophiles are electron-rich species, which has negative or partially negative charge. Lewis bases are nucleophiles, which donate electron pair.

舧 Substitution reaction: A reaction in which one of the hydrogen atoms of a hydrocarbon or a functional group is substituted by any other functional group is called substitution reaction.

舧 Elimination reaction: A reaction in which two substituent groups are detached and a double bond is formed is called elimination reaction.

舧 Addition reaction: It is the reaction in which unsaturated bonds are converted to saturated molecules by the addition of molecules.

舧 The reaction in which hydrogen is added to the compound in the presence of catalyst is known as hydrogenation.

舧 The number of moles of hydrogen absorbed will be equal to the number of double bonds.

舧 The reaction in which a halide group is removed to form an alkene is called dehydrohalogenation.

舧 This reaction in which ${\text{CO}}_{\text{2}}$ is removed from alkene molecules is called decarboxylation reaction.

舧 Acetylation refers to the process of introducing an acetyl group into a compound. A reaction involving te replacement of the hydrogen atom of a hydroxyl or amine group with an acetyl group. Acetic anhydride is commonly used as an acetylating agent.

舧 Piperidine is a heterocyclic amine containing six membered rings, which contains five methyl groups and one nitrogen atom.

舧 Nitrous acid $\left({\text{HNO}}_2\right)$ is produced by the reaction of strong hydrochloric acid (HCl) and aqueous sodium nitrite $\left({\text{NaNO}}_2\right)$ at a low temperature.

舧 Nitrous acid is used to make diazonium salts from amines.

舧 The reaction of primary aryl amine with nitrous acid gives arenediazonium salt.

舧 The nitro compounds formed by direct nitration reaction undergo reduction to give primary aryl amine.

舧 The diazonium group is easily replaced by another group.

舧 In Sandmeyer reaction, arenediazonium salt reacts with cuprous bromide, cuprous cyanide, and cuprous chloride, and the replacement of diazonium group by $–\text{Br}$ >, $–\text{CN}$ >, $–\text{Cl}$ takes place.

舧 The replacement of diazonium group by $–\text{I}$ takes place when arenediazonium salt reacts with potassium iodide.

舧 The replacement of diazonium group by $–\text{H}$ takes place when arenediazonium salt reacts with hypophosphorus acid ${\text{H}}_{\text{3}}{\text{PO}}_2$ >.