P-Aminoacetophenone

Inclusion of a para acetyl group requires a somewhat different approach to the preparation of these compounds. Reaction of the diazonium salt from p-aminoacetophenone with sulfur dioxide affords the sulfonyl chloride, 203 this is then converted to the sulfonamide, 204, Elaboration via the carbamate with cyclohexyl-amine affords acetohexamide (205). ... 

In a number of other cases it has been reported or implied that a single diastereomeric pinacol was formed, but the stereochemistry of the product was not determined these reports come from studies upon the electrochemical reduction of 3-acetylpyridine 87), p-acetamidobenzaldehyde 9I>, (3-di-methylaminopropiophenone 91 p-aminoacetophenone (which affords one pinacol in acid and the other in alkali)92), and the reduction of a mixture of p-dimethylaminoacetophenone and p-methoxyacetophenone to afford a mixed pinacol (87) 93>. 

The conversion of hydrazobenzene into the isomeric benzidine— discovered by the Russian chemist Zinin in the year 1846—is started catalyticaUy by mineral acids and results from the tendency of the molecule to pass into a form possessing less energy, i.e. into a more saturated condition. The reaction is suitably classified with those of which the chief characteristic is that a substituent united to nitrogen exchanges its point of attachment with an H-atom of the nucleus— usually an H-atom in the p-position. To this class belong the conversion of phenylsulphaminic acid into sulphanilic acid (p. 198), of phenyl-hydroxylamine into p-aminophenol (p. 176), and also of acetanilide into p-aminoacetophenone and of N-chloroacetanilide into p-chloro-acetanilide ... 

Some para-substituted anilines in strongly hydrogen bonding solvents show two non-equivalently hydrogen bonded species with differently hybridized aniline nitrogens72 rehybridization of aromatic amino nitrogens depends on the OH acidity of the solvent molecule and the basicity of the substituted anilines. 14 shows three possible modes of interaction of p-aminoacetophenone and acohol, where the amino group is simultaneously both a proton donor and an acceptor. 

Figure 21. Conversion of substituted anilines (OT, MT, and PT are respective ortho-, meta-, and para-toluidine, PA = p-anisidine, and PAA = p-aminoacetophenone), corresponding mono-N-methylated anilines selectivity and yield obtained on Cu0.5Zn0.5Fe204 at 300oC with methanol. Only in the case of PAA, feed with CH30H PAA = 6 was employed to avoid solubility problem, and in all other cases a CH30H Sub. Amline H20 = 3 1 1 was maintained. Reprinted from Applied Catalysis A General, 320, Vijayaraj M., et al., 2007, 64-68 with permission from Elsevier.

Ethyl-a-Keto-y-dimethylaminobutyrate p-Acetylphenylhydrazone. (JMC, 7, 144 (1966)). 40 g of p-aminoacetophenone in 250 ml of water and 143 ml of coned hydrochloric acid is diazotized at 0-5° with 21 g of sodium nitrite in 200 ml of water. To the resulting solution is added 60.3 g of ethyl a-(2-dimethylaminoethyl)aceto-acetate followed by 63 g of sodium acetate. Raise the pH to 6.5 and maintain with the addition of 3 N NaOH (also use the 3 N for the initial raise to 6.5). Stir, with external cooling for 2 hours, make basic, and extract with three 400 ml portions of ehloroform. Combine the extracts and dry over sodium sulphate, eoneentrate in vacuo. Crystallize the residue with a mixture of benzene-petroleum ether, after purification with charcoal, to get 65 g. Crystallize two more times to get a melting point of 84-85°. 

Commercial grades of acetone and p-aminoacetophenone (Matheson Coleman and Bell or Aldrich Chemical Company, Inc.) were used without further purification. 

The CCH of p-nitroacetophenone (5) (Scheme 2) was inefficient and unselective giving p-aminoacetophenone (6) in about 20% yield together with some 10-12% of unindentified compounds (30% mass balance). Attempts to recover more material were unsuccessful. The ECH at a RCu cathode in an alkaline (0.28 M KOH, pH 13.5) MeOH-HzO (1.5% of H2O) solution was reported to give exclusively p-amino-acetophenone (6) (79% yield of isolated product) (3,8). 

The procedure reported here provides a convenient method for the a-hydroxylation of ketones which form enolates under the reaction conditions. The reaction has been applied successfully to a series of para-substituted acetophenones, 1-phenyl-1-propanone, 3-pentanone, cyclopentanone, cyclohexanone, cycloheptanone, cyclododecanone, 2-methyl cyclohexanone, 2-norbornanone and benzalacetone. In the case of a steroidal example it was shown that a carbon-carbon double bond and a secondary hydroxyl group are not oxidized. A primary amino function, as in the case of p-aminoacetophenone, is not affected.5 Similarly, a tertiary amino ketone such as tropinone undergoes the a-hydroxy at ion reaction.5... 

The 1,2,5-benzothiadiazepine 1,1-dioxide (518) and its 3,4-dihydro analogue have been prepared by the reaction of 2-nitrobenzenesulfonyl chloride with (p-aminoacetophenone to give (517) followed by reductive cyclization (79JHC835). 

Wu and Iin [48] have described a spectrophotometric method for the determination of micro amounts of nitrite in soil. The chromogenic reagents were p-aminoacetophenone and resorcinol in sodium carbonate-sodium ac-... 

Sodium nitrite Hydrogen chloride Ammonia p-Aminoacetophenone Sulfur dioxide Cyclohexyl isocyanate ... 

In this manner Scheller has been able to convert p nitroaniline and p-aminoacetophenone to the corresponding arsonic acids. 

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