Quiz - Benzylic and Aromatic Reactions - 2 | Benzylic and Aromatic Reactions of Substituted Benzene
Organic Chemistry 3 - Quiz - Benzylic and Aromatic Reactions - 2
What is the major product of benzylic oxidation when toluene is treated with potassium permanganate under acidic conditions?
Toluene undergoes benzylic oxidation with potassium permanganate, especially under acidic conditions, to form benzoic acid. This reaction occurs because the benzylic position is particularly reactive towards oxidation due to the resonance stabilization of potential intermediates.
During nitrobenzene reduction using iron and hydrochloric acid, what is the primary intermediate that is further hydrolyzed to form aniline?
In the reduction of nitrobenzene using iron and hydrochloric acid, phenylhydroxylamine is formed as an intermediate, which upon further hydrolysis, yields aniline. This reduction reaction highlights the importance of the nitro group transformation in aromatic chemistry.
Which reaction condition does not favor nucleophilic aromatic substitution?
Nucleophilic aromatic substitution reactions typically require polar or polar aprotic solvents to facilitate the reaction, especially since many nucleophiles are ionic in nature. Electron-withdrawing groups and high temperatures generally promote this reaction.
When aniline reacts with diazotization agents, what type of compound is primarily formed?
The reaction of aniline with diazotization agents, typically a nitrous acid formed in situ, results in the formation of benzene diazonium salts. This reaction is a cornerstone of aromatic substitution, allowing a diverse array of subsequent transformations.
What is the unique aspect of the elimination-addition mechanism via benzyne intermediate?
The mechanism involving a benzyne intermediate is unique because it temporarily disrupts the aromaticity of the benzene ring. This highly reactive intermediate is generated under extreme conditions and is capable of undergoing addition reactions to restore aromaticity.
What is a significant advantage of the Schiemann reaction compared to other substitution reactions of aryldiazonium salts?
The Schiemann reaction allows for the selective substitution of the diazo group with a fluorine atom, providing a convenient method for introducing fluorine-containing groups onto aromatic rings.
What characteristic property do azo compounds exhibit due to their highly conjugated structure?
Azo compounds are highly conjugated and often exhibit intense coloration, making them valuable as synthetic dyes.
How does the benzylic oxidation differ when applied to an alkyl side chain with a tertiary carbon, compared to toluene?
Benzylic oxidation typically fails when the benzylic carbon is tertiary, as seen in tert-butylbenzene. The absence of a benzylic hydrogen prevents the formation of the benzylic radical or cation intermediate required for further oxidation.
What is the predominant pattern of substitution observed in azo coupling reactions, unless another substituent is present?
Para substitution is typically observed in azo coupling reactions, unless another substituent is already present on the aromatic ring.
What chemical feature enhances the reactivity of phenols towards electrophilic aromatic substitution?
This conjugation increases electron density on the ring, making phenols more reactive towards electrophilic aromatic substitution. The hydroxyl group serves as an activating and ortho/para-directing group because of this conjugation.