Diazonium Salts & Nucleophilic Aromatic Substitution: Crash Course Organic Chemistry

The video explores the chemistry behind food additives like sodium nitrite, which enhances color and prevents bacterial growth. It delves into the reactions of nitrous acid with amines, leading to the formation of diazonium salts, and discusses their instability and potential applications. The video also covers the stability of aryl diazonium salts and their use in creating azo dyes, which are common in food coloring. It contrasts electrophilic and nucleophilic aromatic substitution reactions, providing examples and synthesis problems to illustrate these concepts.

What is the primary role of sodium nitrite in cured meats?

• To increase shelf life

• To act as a preservative

• To prevent bacterial growth

• To enhance flavor

What does nitrous acid form when it reacts with primary amines?

• A diazonium salt

• A soluble salt

• Nitrogen gas

• Nitrosamine

What is a key characteristic of alkyl diazonium salts?

• They are highly stable

• They are unstable

• They are used in food coloring

• They form stable carbocations

What is the Tiffeneau-Demjanov rearrangement used for?

• To form diazonium salts

• To create cyclic ketones

• To stabilize alkyl diazonium salts

• To produce azo dyes

What makes aryl diazonium salts more stable than alkyl diazonium salts?

• Lack of resonance

• Stronger bonds

• Higher nitrogen content

• Presence of aromatic rings

Which sequence is crucial in aromatic chemistry for creating substituted benzenes?

• Nitration, reduction, diazotization, substitution

• Reduction, nitration, substitution, diazotization

• Substitution, diazotization, nitration, reduction

• Diazotization, substitution, nitration, reduction

What is the role of electron-withdrawing groups in nucleophilic aromatic substitution?

• They deactivate the reaction

• They speed up the reaction

• They have no effect

• They slow down the reaction

In nucleophilic aromatic substitution, what is the role of the aromatic ring?

• Catalyst

• Electron donor

• Neutral

• Electron acceptor

What is the final product when starting with chlorobenzene to make 4-cyanophenol?

• A phenol

• A nitrile

• A diazonium salt

• A substituted benzene

What is the correct order of steps to synthesize 4-cyanophenol from chlorobenzene?

• Reduction, diazotization, nitration, substitution

• Nitration, reduction, diazotization, substitution

• Substitution, nitration, reduction, diazotization

• Diazotization, substitution, nitration, reduction