Organic reactions electrophilic aromatic substitution

We call this reaction electrophilic aromatic substitution it is one of the fundfflnental processes of organic chemistry. 

Electrophilic aromatic substitution reactions are important for synthetic purposes and also are one of the most thoroughly studied classes of organic reactions from a mechanistic point of view. The synthetic aspects of these reactions are discussed in Chapter 11 of Part B. The discussion here will emphasize the mechanisms of several of the most completely studied reactions. These mechanistic ideas are the foundation for the structure-reactivity relationships in aromatic electrophilic substitution which will be discussed in Section 10.2... 

The mechanistic spectrum shed new light on a familiar textbook example of organic reactions, i.e., electrophilic aromatic substitution (Scheme 9). 

Chapter 11 focuses on aromatic substitution, including electrophilic aromatic substitution, reactions of diazonium ions, and palladium-catalyzed nucleophilic aromatic substitution. Chapter 12 discusses oxidation reactions and is organized on the basis of functional group transformations. Oxidants are subdivided as transition metals, oxygen and peroxides, and other oxidants. 

A diverse group of organic reactions catalyzed by montmorillonite has been described and some reviews on this subject have been published.19 Examples of those transformations include addition reactions, such as Michael addition of thiols to y./bunsatu rated carbonyl compounds 20 electrophilic aromatic substitutions,19c nucleophilic substitution of alcohols,21 acetal synthesis196 22 and deprotection,23 cyclizations,19b c isomerizations, and rearrangements.196 24... 

Despite the use of new catalys.s for manufacturing some industrial organic chemicals, many well-known classical reactions still abound. The Friedel-Crafts alkylation is one of the first reactions studied in electrophilic aromatic substitution. It is used on a large scale for making ethylbenzene. 

The most familiar set of organic reactions is perhaps the electrophilic aromatic substitutions. For monosubstituted benzenes the major products from the process are either o- or p-disubstituted benzenes or m-disubstituted analogs. 

However, the formation of molecular complexes between nucleophile and electrophile (with a possible participation of solvents) in both electrophilic aromatic substitutions and nucleophilic aromatic substitutions is clearly expected, as shown by the conventional use of the terms electrophile and nucleophile these reactions belong to apparently different fields of organic chemistry, but the unification of the two kinds of reaction is mainly a matter of terminology and of details. 

Given the reactants, write the structures of the main organic products of the common electrophilic aromatic substitution reactions (halogenation, nitration, sulfonation, alkylation, and acylation). 

Fukui functions and local softnesses and their application in typical organic reactions (electrophilic substitutions on aromatic systems, nucleophilic additions to activated carbon-carbon double and triple bonds) [34-39]. 

Figure 3 Direct pathways of ozone reaction with organics. (A) Criegge mechanism. (B) Electrophilic aromatic substitution and 1,3-dipolar cycloaddition. (C) Nucleophilic substitution.

The most common reaction of aromatic compounds is electrophilic aromatic substitution. Many different substituents can be introduced. .. Starting from only a few simple materials, we can prepare many thousands of substituted aromatic compounds. J. McMurry, Organic Chemistry, 5 th Ed., Brooks/Cole, Pacific Grove, CA, 2000, p. 592. 

The study of the structure, synthesis, and reactivity of aromatic compounds has been one of the cornerstones of the teaching of organic chemistry. An account of the historical and sometimes disputed dream of Kekule [1] is followed by the beautiful logic of electrophilic aromatic substitution rules [2], which allows students to predict syntheses of sparsely substituted aromatics. Aside from a brief diversion into reactions of halonitrobenzenes with nucleophiles [3], this topic constitutes a large chapter in our 1st year organic education but by the time we teach upper year organic majors and graduate students, aromatic chemistry... 

Solid acid catalysts are, in principle, applicable to a plethora of acid-promoted processes in organic synthesis [27-29]. These include various electrophilic aromatic substitutions, e.g. nitrations, and Friedel-Crafts alkylations and acylations, and numerous rearrangement reactions such as the Beckmann and Fries rearrangements. 

Pertinent examples of zeolite-catalyzed reactions in organic synthesis include Friedel-Crafts alkylations and acylations and other electrophilic aromatic substitutions, additions and eliminations, cyclizations, rearrangements and isomeriza-tions, and condensations. 

Because the elementary reactions of cationic alkene polymerizations are directly related to the organic chemistry of carbocations, Chapter 2 will investigate electrophilic additions to double bonds, nucleophilic substitution, electrophilic aromatic substitution, and elimination reactions. 

Cationic intermediates are considered the active species in many organic reactions, as well as in cationic polymerizations. For example, cationic intermediates are postulated in both electrophilic addition and elimination reactions. They are also involved in electrophilic aromatic substitutions and in some nucleophilic aliphatic substitutions. The latter reactions may involve either onium or carbenium ions. The current understanding of... 

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