The major mechanism of aromatic rings is:

Question

BlackTom AI · Accepted Answer

When evaluating the major mechanism of aromatic rings, we start by considering the typical reaction pathway used to modify benzene and related systems. 
Option 1: 'nucleophilic acyl substitution' involves replacement at a carbonyl-adjacent center via nucleophilic attack, which is characteristic of acyl transfer processes in acyl chlorides or esters, not the classic aromatic ring chemistry. This is not the standard pathway for substituting or adding to an intact aromatic ring. 
Option 2: 'nucleophilic acyl addition' describes a mechanism where a nucleophile adds to a carbonyl group without displacing substituents, such as in aldehydes or ketones, and again does not reflect the common aromatic substitution pattern on benzene rings. 
Option 3: 'electrophilic aromatic substitution' is the quintessential mechanism by which aromatic rings undergo functionalization: an electrophile attacks the π-system to form an arenium ion intermediate, followed by deprotonation to restore aromaticity. This framework explains many classic transformations like nitration, sulfonation, halogenation, and alkylation/acylation under Friedel–Crafts conditions. 
Option 4: 'electrophilic addition' would imply the ring loses aromaticity by undergoing a direct addition of an electrophile across a double bond without subsequent re-aromatization; however, stable aromatic systems prefer pathways that re-establish aromaticity, making simple electrophilic addition incompatible with the dominant aromatic chemistry in many contexts. 
Option 5: 'SN2' is a backside displacement typical of aliphatic substrates with good leaving groups, not a mechanism that operates on the delocalized π-system of an aromatic ring to form substituents while preserving or restoring aromaticity. This lacks relevance to the standard aromatic substitution repertoire. 
Option 6: 'other' would apply only if there were a mechanism not covered by the common options, but the well-established major pathway for aromatic rings is clearly provided by option 3, with abundant experimental and theoretical support describing its steps and outcomes. 
By comparing these options, the electrophilic aromatic substitution route best matches the widely taught and observed behavior of aromatic rings undergoing functionalization while maintaining aromatic stability, whereas the other mechanisms describe processes that either do not apply to intact rings or fail to account for the preservation of aromaticity during reaction.

CHE 008B A01 SS1 2025 Lecture 4 - Electrophilic Aromatic Substitution

The major mechanism of aromatic rings is:

查看解析

登录即可查看完整答案

类似问题

Which of the following, will provide a meta, nitro (NO2) compound, upon nitration with HNO3/H2SO4?

Which of the following is true about an ACTIVATOR for electrophilic aromatic substitution? (select all that apply)

更多留学生实用工具

考试浏览器助手

风格化写作助手

论文查重助手

文献引用助手

课堂转译助手

课堂笔记助手

Quiz搜索助手

学校历年真题

智能刷题助手

智能匹配练习

希望你的学习变得更简单