Acetanilide, electrophilic aromatic

Acetanilide, electrophilic aromatic substitution of, 939-940 Acetate ion, bond lengths in, 43 electrostatic potential map of, 43, 53, 56, 757 resonance in, 43 Acetk acid, bond angles in, 755 bond lengths in, 755 dimer of, 755 dipole moment of, 39 electrostatic potential map of, 53, 55... 

Acetanilide is quite similar to anisole in its behavior toward electrophilic aromatic substitution. 

Acetanilide, having a much less basic N atom compared to aniline, undergoes electrophilic aromatic substitution under Friedel-Crafts conditions, forming a mixture of ortho and para products. 

Acetanilide reacts with chlorosulfonic acid in an electrophilic aromatic substitution ... 

Qi) Acetanilide is a reactive substrate toward electrophilic aromatic substitution. On reaction with chloroacetyl chloride, it undergoes Friedel-Crafts acylation, primarily at its para position. 

Acetylation of aniline produces acetanilide (2) and protects the amino group from the reagent to be used next. Treatment of 2 with chlorosulfonic acid brings about an electrophilic aromatic substitution reaction and yields/>-acetamidobenzene-sulfonyl chloride (3). Addition of ammonia or a primary amine gives the diamide, 4 (an amide of both a carboxylic acid and a sulfonic acid). Finally, refluxing 4 with dilute hydrochloric acid selectively hydrolyzes the carboxamide linkage and produces a sulfanilamide. (Hydrolysis of carboxamides is much more rapid than that of sulfonamides.)... 

Bromine is a good electrophile, and acetanilide a good nucleophile, due to the presence of the donating amide nitrogen. Electrophilic aromatic substitution (SfAr) by the bromine gives the aryl bromide product, in which substitution of Br" occurs at the o-position. 

Sodium bisulfite is used to discharge the yellow color produced in the electrophilic aromatic bromination of acetanilide. 

Compared to Br2/HOAc, Br2/FeBrj is a more powerful combination of reagents for effecting electrophilic aromatic bromination. What difficulty might arise if this combination were used for brominating acetanilide ... 

Purpose. This experiment extends our understanding of the experimental conditions under which electrophilic aromatic substitution reactions are carried out (also see Experiments [27] and [29A]-[29D]). It deals with electrophilic aromatic halogenation. The directive influence of the acetamido, —NHCOCH3, group on the bromination of acetanilide is explored. 

How do you account for the fact that N-phenylacetamide (acetanilide) is less reactive toward electrophilic aromatic substitution than is aniline ... 

Udenfriend et al. observed that aromatic compounds are hydroxyl-ated by a system consisting of ferrous ion, EDTA, ascorbic acid, and oxygend Aromatic and heteroaroinatic compounds are hydroxylated at the positions which are normally most reactive in electrophilic substitutions. For example, acetanilide gives rise exclusively to the o-and p-hydroxy isomers whereas quinoline gives the 3-hydroxy prod-uct. - The products of the reaction of this system w ith heterocyclic compounds are shown in Table XIII. 

Our recent studies on effective bromination and oxidation using benzyltrimethylammonium tribromide (BTMA Br3), stable solid, are described. Those involve electrophilic bromination of aromatic compounds such as phenols, aromatic amines, aromatic ethers, acetanilides, arenes, and thiophene, a-bromination of arenes and acetophenones, and also bromo-addition to alkenes by the use of BTMA Br3. Furthermore, oxidation of alcohols, ethers, 1,4-benzenediols, hindered phenols, primary amines, hydrazo compounds, sulfides, and thiols, haloform reaction of methylketones, N-bromination of amides, Hofmann degradation of amides, and preparation of acylureas and carbamates by the use of BTMA Br3 are also presented. 

Aromatic amines are less basic than aliphatic amines and the basicity is influenced by substituents on the aromatic ring. The reactivity of amines is modified by conversion to amides such as acetanilide. These still undergo electrophilic attack in the ortho and para positions. 

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