Acetic anhydride Acetaminophen

Acetic anhydride Acetaminophen Acetazolamide Acetrizoate sodium Acetyl cysteine Acetyl sulfisoxazole Afloqualone... 

Acetic anhydride is often used to prepare acetate esters from alcohols and AT-substituted acetamides from amines. For example, aspirin (acetyl-salicylic acid) is prepared commercially by the acetylation of o-hydroxy-benzoic acid (salicylic acid) with acetic anhydride. Acetaminophen, a drug used in over-the-counter analgesics such as Tylenol, is prepared by reaction of p-hydroxyaniline with acetic anhydride. Note that the more nucleophilic -NH2 group reacts, rather than the less nucleophilic -OH group. 

However, this method is appHed only when esterification cannot be effected by the usual acid—alcohol reaction because of the higher cost of the anhydrides. The production of cellulose acetate (see Fibers, cellulose esters), phenyl acetate (used in acetaminophen production), and aspirin (acetylsahcyhc acid) (see Salicylic acid) are examples of the large-scale use of acetic anhydride. The speed of acylation is greatiy increased by the use of catalysts (68) such as sulfuric acid, perchloric acid, trifluoroacetic acid, phosphoms pentoxide, 2inc chloride, ferric chloride, sodium acetate, and tertiary amines, eg, 4-dimethylaminopyridine. 

Write the mechanism of the reaction between p-hydroxyaniline and acetic anhydride to prepare acetaminophen. 

Acetylium tetrailuoroborate, 4 144t N-Acetyl-p-aminophenol (acetaminophen), acetic anhydride used in production of, 1 158. See also Acetaminophen Acetyl perchlorate, 1 157 Acetylsalicylic acid (aspirin), 22 17-21 acetic anhydride used in production of, 1 158... 

The different reactivities associated with nucleophiles and leaving groups is nicely exemplified in the synthesis of the analgesic drug paracetamol (USA acetaminophen) from 4-aminophenol. If 4-aminophenol is treated with an excess of acetic anhydride, aeetylation of both amino and phenol groups is observed, and the product is the diacetate. Paracetamol is the A-acetate of 4-aminophenol, so how might mono-acetylation be achieved There are two approaches. 

Acetaminophen Acetaminophen, p-acetaminophenol (3.2.80), is synthesized by reacting p-aminophenol with acetic anhydride [76,77]. 

Acetaminophen, sold under the trade name Tylenol, is a widely used analgesic and antipyretic that is an over-the-counter drug. Combined with codeine it is one of the top five prescription drugs. Acetaminophen is prepared by treating p-aminophenol with a mixture of glacial acetic acid and acetic anhydride. 

Problem 16.17 The pain reliever acetaminophen is produced by reacting 4-aminophenol with acetic anhydride. Outline a synthesis of acetaminophen from 4-aminophenol including any needed inorganic reagents. <... 

Acetamidosalicylic acid, 994 Acetaminophen, 849 Acetmiilide, 312 Acetarsol, 313 Acetarsol sodium, 313 Acetarsone, 313 Acetate buffer (pH 5), 1169 Acetazolam, 313 Acetazolamide, 313 Acetazolamide sodium, 313 Acetazoleamide, 313 Acetcarbromal, 317 Acethydrocodone, 1007 Acetic acid, 314, 1169 (metabolite), 312, 851 Acetic acid, concentrated, 314 Acetic acid, dilute, 1169 Acetic acid, glacial, 314 Acetic aldehyde, 311 Acetic anhydride, 188 Acetic ether, 602 Acetohexamide, 314 Acetomenadione, 315 Acetomenaphthone, 315 Acetomorphine, 524... 

Anhydrides react with alcohols and amines with ease, so they are often used in the laboratory to prepare esters and amides. For example, acetic anhydride is used to prepare two analgesics, acetylsalicylic acid (aspirin) and acetaminophen (the active ingredient in Tylenol). 

Acetaminophen, U5P. Acetaminophen. Af-Acetyl-p-aminophcnol. 4-hydroxyacetanilide. APAP (Panado. Tem-pra. Tylenol, etc.), may be prepared by reduction of p-ni-trophenol in glacial acetic acid, acetylation of p-aminophenol with acetic anhydride or ketene. or from p-hydroxy-acetophenonc hydrazonc. It occurs as a white, odorless. slightly bitter crystalline powder. It is slightly soluble... 

Nitrobenzene on being subjected to electrol3dic reduction in the presence of sulphuric acid yields para-aminophenol which on treatment with acetic anhydride and sodium acetate gives rise to the production of acetaminophen (or paracetamol). 

The analgesic acetaminophen is synthesized by treating 4-aminophenol with one equivalent of acetic anhydride. Write an equation for the formation of acetaminophen. Hint. Remember from Section 7.5A that an — NH2 group is a better nucleophile than an — OH group.) (See Example 14.5)... 

Preparation of acetaminophen involves treating an amine with an acid anhydride to form an amide. In this case, p-aminophenol, the amine, is treated with acetic anhydride to form acetaminophen (p-acetamidophenol), the amide. 

In the reaction between p-aminophenol and acetic anhydride to form acetaminophen, 0.450 mL of water was added. What was the purpose of the water ... 

If 0.130 g of p-aminophenol is allowed to react with excess acetic anhydride, what is the theoretical yield of acetaminophen in moles In grams ... 

Acetic anhydride, CH3C(0)0C(0)CH3, is an important industrial reagent used to prepare acetamides, CH3C(0)NR2, from a variety of amines. For example, acetaminophen, an over-the-counter analgesic, is synthesized by the reaction of p-hydroxy-aniline with acetic anhydride ... 

The analgesic acetaminophen is synthesized by treating 4-aminophenol with one equivalent of acetic anhydride. Draw a structural formula for acetaminophen. 

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