Acetamidation aromatic compounds

However, under close examination this reaction was found to correspond to the simple case shown in Fig. 2 48 50 Sodium acetate-acetic acid has an anodic limit of about 2.0 V vs. SCE, whereas both anisole and naphthalene (and a large number of other substrates) have half-wave potentials far below this value. Controlled potential electrolysis (cpe) at low anode potentials showed that aryl acetates indeed were formed via discharge of the aromatic compound and not acetate ion. Another case in which the mechanism is clearly indicated by results from cpe is anodic acetamidation of alkylaromatics 1 and aliphatic compounds 44l... 

A. Olefinic compounds Acetylenic compounds Aromatic compounds Carbonyl compounds F/c-Oxygen compounds Nitrogen compounds Sulfur compounds Halogen compounds Other heteroatom compounds Organometallic compounds Stereoselective and Stereospecific Electrooxidation A. Carboxylic acids Acetoxylation Methoxylation Acetamidation... 

Anodic oxidation of n-alkanes in acetonitrile results in mixtures of A -s-alkylacetamides but skeletal rearrangement of the intermediate i-carbenium ions is not observed. Aromatic compounds can undergo direct acetamidation in the ring. Thus, acetophenone, which normally undergoes electrophilic aromatic substitution at the meta position, affords the o- and p-acetamides (Scheme 44). Anthracene is cleanly converted into the acetamide (84) when the reaction is performed in the presence of TFAA as water scavenger (equation 41). ... 

Azocompounds Acetamides Aromatic/Heterocyclic amines Nitro compounds Nitrenium ions, tautomeric carbonium ions... 

Sometimes, the exchange does not work well under reflux conditions. A few alternatives are the use of phase transfer catalysts (ammonium or phosphonium salts), crown ethers, or exchange in melts or under solid-state conditions (Apparu and Madelmont, 1998). Melts are either the substrate itself at its melting point (where it has to be stable, and must have a high dielectric constant to solubilize Na I), a melt of acetamide or formamide, or ammonium sulfate below its melting point (reaction at 120—160°C). This technique is mostly used with aromatic compounds (Seevers and Counsell, 1982). 

Electrooxidation of aromatic compounds has been intensively investigated, and many useful fine chemicals have been prepared by both side-chain and aromatic nucleus oxidation. Side-chain oxidation of alkylbenzenes may furnish benzyl alcohols, benzyl acetates, benzyl methyl ethers, Af-benzyl acetamides, benzaldehydes, benzoic acids, and so on. For instance, electrooxidation of p-methoxytoluene affords p-methoxybenzyl methyl ether, p-methoxybenzaldehyde, and/or its dimethylacetal depending on the choice of electrolysis media [3]. Many examples of electrooxidation of aromatic nucleus have been also reported. p-Quinones and their methyl acetals and semiquinones are prepared by electrooxidation of phenol derivatives and hydroquinones [3]. Nucleus-nucleus coupling of methoxybenzene derivatives... 

The inclusion of aromatic rings as part of the side chains results in quite potent agents, possibly because the rigid rings better define the position of the basic nitrogen. Reaction of para-hydroxyacetanilide (19-1) with formaldehyde and diethylamine affords the corresponding Mannich product (19-2) hydrolysis of the acetamide then leads to the aniline (19-3). Treatment of that compound with dichloro-quinoline (17-6) leads to the displacement of chlorine on the heterocyclic ring and the formation of amodiaquine (19-4) [21]. 

Insertions into the metal - oxygen bond in mercuric acetate with aromatic isocyanides has given the compound 119 (R = Ph, xylyl), which readily hydrolyzed to give organic acetamide derivatives (480). 

Carbanions from hydrocarbons, nitriles, ketones, esters, TV./V-dialkyl acetamides and thioamides, and mono and dianions from (3-dicarbonyl compounds are some of the most common nucleophiles through which a new C-C bond can be formed. This C-C bond formation is also achieved by reaction with aromatic alkoxides. Among the nitrogen nucleophiles known to react are amide ions to form anilines however, the anions from aromatic amines, pyrroles, diazoles and triazoles, react with aromatic substrates to afford C-arylation. 

The carbanions derived from A,A-disubstituted amides and lactams react with certain aromatic halides in liquid ammonia under photostimulation [85,86] to form the expected a-arylated compounds in good yields. Unsymmetrical a, a-diaryl amides can be formed by reaction of aryl halides with the anion of the oc-aryl-A,7V-dimethyl acetamides [85]. 

A one-pot synthesis of 3,5-disubstituted 7-hydroxy-3//-l,2,3-triazolo[4,5-d]pyrimidines (130) has been carried out by using benzyl azide, cyano-acetamide, ethyl or methyl esters of the appropriate carboxylic acid, and sodium ethoxide as catalyst. The reaction proceeds via a 5-amino-l-benzyltriazole-4-carboxamide intermediate (85JHC1607). 7-Amino-3H-l,2,3-triazolo[4,5-d]pyrimidines 133 (R2 = H) were prepared starting from benzyl azide, malononitrile, and an aliphatic or aromatic nitrile, or by reaction of 130 with phosphorus oxychloride followed by amination. Compound 132 was formed in most reactions from two molecules of the 5-amino-4-cyano-l-benzyltriazole intermediate by an intermolecular nucleophilic at-... 

At a Pt anode, aromatic carbonyl compounds undergo fairly efficient nuclear acetamidation in moist MeCN with Et4NBp4 as supporting electrolyte [129]. 

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