Acetophenone 6>-carboxylic acid

When an alkyl aryl ketone is heated with yellow ammonium polysulphide solution at an elevated temperature, an aryl substituted aliphatic acid amide is foimed the product actually isolated is the amide of the ci-aryl carboxylic acid together with a smaller amount of the corresponding ammonium salt of the oarboxylio acid. Thus acetophenone affords phenylacetamide (50 per cent.) and ammonium phenylacetate (13 per cent.) ... 

Ethers of benzenepentol have been obtained by Dakin oxidation of the appropriately substituted acetophenone. Thus, the oxidation of 2-hydroxy-3,4,6-ttimethoxyacetophenone and 2-hydroxy-3,4,5-ttimethoxyacetophenone with hydrogen peroxide ia the presence of alkali gives l,2-dihydroxy-3,4,6-ttimethoxybenzene and l,2-dihydroxy-3,4,5-ttimethoxybenzene, respectively further methylation of these ethers yields the pentamethyl ether of benzenepentol (mp 58—59 degC) (253). The one-step aromatization of myoinositol to produce esters of pentahydroxybenzene is achieved by treatment with carboxylic acid anhydrides ia DMSO and ia the presence of pyridine (254) (see Vitamins). 6-Alkyl- or... 

The carboxylation of ketones is carried out essentially as in the preceding experiment, but at slightly higher temperatures (requiring an oil bath or mantle). Thus, acetophenone (6 g, 0.05 mole) in 100 ml of approx. 2 M MMC is stirred and heated at 110-120° for 1 hour. After cooling, hydrolysis in the acid-ice mixture, and isolation from ether, benzoylacetic acid, mp 99-100°, is obtained in 68% yield. Similarly, 1-indanone gives l-indanone-2-carboxylic acid, mp 100-101°, in 91 % yield. 

Just as an aromatic ring is alkylated by reaction with an alkyl chloride, it is acylated by reaction with a carboxylic acid chloride, RCOC1, in the presence of AICI3. That is, an acyl group (-COR pronounced a-sil) is substituted onto the aromatic ring. For example, reaction of benzene with acetyl chloride yields the ketone, acetophenone. 

Methyl 2-phenylsulfmylacetate 96 and -ketosulfoxides have been used for the syntheses of various ketones and derivatives of carboxylic acids ". For example, co-(methylsulfmyl)acetophenone 97 have been converted to the corresponding ketone or to y- and -ketoesters ... 

Carbanions derived from optically active sulfoxides react with esters, affording generally optically active )S-ketoesters ° . Kunieda and coworkers revealed that treatment of (-t-)-(R)-methyl p-tolyl sulfoxide 107 with n-butyllithium or dimethy-lamine afforded the corresponding carbanion, which upon further reaction with ethyl benzoate gave (-l-)-(R)-a-(p-tolylsulfinyl)acetophenone 108. They also found that the reaction between chiral esters of carboxylic acids (R COOR ) and a-lithio aryl methyl sulfoxides gave optically active 3-ketosulfoxides The stereoselectivity was found to be markedly influenced by the size of the R group of the esters and the optical purity reached to 70.3% when R was a t-butyl group. 

Phenacyl esters of benzoic acid, of amino acid derivatives, and of gib-berillin A3 undergo photolytic cleavage at >313 nm, giving, in each case, the free carboxylic acid and the corresponding acetophenone (see Scheme 29) 84,85 -pijg yjeijs Qf free carboxylic acids (33-96%) vary considerably,... 

Compound (B), being an oxidation product of a ketone should be a carboxylic acid. The molecular formula of (B) Indicates that it should be benzoic acid and compound (A) should, therefore, be a monosubstituted aromatic methyl ketone. The molecular formula of (A) indicates that it should be phenyl methyl ketone (acetophenone). Reactions are as follows ... 

In 2003, Banerjee et al. designed an efficient photoremovable protecting group for the release of carboxylic acids based on similar p-elimination from photoenols (Scheme 14). They showed that o-alkyl acetophenone derivatives with various ester groups in the p-position release their ester moiety in high chemical yields. The authors proposed that the photorelease took place as shown in Scheme 14 but did not support the mechanism with transient spectroscopy. Formation of 21, which is expected to be the major product in the reaction, was not confirmed, and thus, the authors speculated that 21 undergoes polymerization to yield oligomers. 

The reagents RuCl3/Na(Br03) /aq. M Naj(C03) and RuCl3/K3(S30j)/aq. M KOH oxidised activated primary alkyl halides RX to carboxylic acids and secondary alkyl halides to ketones, e.g. 1-bromophenylethane to acetophenone [213]. Stoicheiometrically fran -Ba[Ru(OH)2(0)3]/CF3COOH/(bpy)/CH3Cl3 oxidised alkanes (e.g. cyclohexane, adamantane, n-hexane, ethane) to ketones or acids, perhaps via Ru (0) (bpy)(CF C(O)O) [550]. 

The geometric isomers 464 and 467 of 5(47/)-oxazolones prepared from acetophenones can be separated. Alternatively, the mixture can be isomerized under the appropriate reaction conditions to obtain the pure of (Z) or ) isomer. Each isomer can be converted to a pair of enantiomers 466 and 469 (only one enantiomer shown) (Scheme 7.152). The p-methyl phenylalanine analogues thus obtained are constrained phenylalanines and the effect of incorporation of a p-MePhe or p-MeTyr residue on the biological properties of H-Tyr-Tic-Phe-Phe-NH2 (TIPP, where Tic = l,2,3,4-tetrahydroisoquinoline-3-carboxylic acid) a delta opioid receptor antagonist, has been studied. ... 

A hydroxymethyl group can be introduced (ArH —> ArCH2OH) by several variations of this method.345 Alkylation of these substrates can also be accomplished by generating the alkyl radicals in other ways from hydroperoxides and FeS04,346 from alkyl iodides and H Oi-FefH),347 from carboxylic acids and lead tetraacetate, or from the photochemically induced decarboxylation of carboxylic acids by iodosobenzene diacetate.348 The reaction has also been applied to acetophenone and ferrocene.349... 

The carbonyl group in condensed 4f/-pyran 263b was reduced by condensation with tosylhydrazine followed by borohydride.290 The aldehyde group in 607b was aldolized with acetophenone to unsaturated ketone 607c or oxidized to carboxylic acid 607d with molecular oxygen.86... 

Alternatively the oxidation of 4 -(methylsulfonyl) acetophenone with S8 and morpholine produces the 2-(4-(methylsulfonyl)phenyl)acetic acid ethyl ester (xiv), which is condensed with 2-methylpyridine-3-carboxylic acid methyl ester by means of terf-butyl magnesium chloride in hot tetrahydrofurane to give the ketosulfone (ix). 

Acetonitrile, 407 Acetophenone, 725,729,730 phenylhydrazone, 852 p-Acetotoluidide, 593, 605 Acetoxime, 343 Acetylacetone, 861, 862, 863 Acetylation, reductive, 749 Thiele, 749 Acetyl chloride, 367 2-Acetylcyciohexanone, 862, 864 Acetylene, 245, 897 reactions of, 245, 246 Acetylenic compounds, synthesis of, 467-469, 895-902 Acetylglycine, 909 Acetylmethylurea, 968, 969 Acetylsalicylio acid, 996 Acetyl-o-toluidide, 578 2-Acetylthiophene, 837 Acid anhydrides of aliphatic carboxylic acids, 371... 

Friedel-Crafts Acylation, The Friedel-Crafts acylation procedure is the most important method for preparing aromatic ketones and their derivatives. Acetyl chloride (acetic anhydride) reacts with benzene in the presence of aluminum chloride or acid catalysts to produce acetophenone [98-86-2], CgHgO (1-phenylethanone). Benzene can also be condensed with dicarboxylic acid anhydrides to yield benzoyl derivatives of carboxylic acids. These benzoyl derivatives are often used for constructing polycyclic molecules (Haworth reaction). For example, benzene reacts with succinic anhydride in the presence of aluminum chloride to produce p-benzoylpropionic acid [2051-95-8] which is converted into a-tetralone [529-34-0] (30). 

The carbonyl bases constitute another important class of weak bases that present interesting possibilities for investigation of structural effects. In solution, experiments with these compounds are subject to severe difficulties. The result is a serious lack of agreement among different investigators about pAa. Arnett and co-workers point out that pKa values reported for acetophenone cover a range of over four units ( — 3.65 to —7.99), while those for acetone span seven units (-0.2 to -7.2).102 In view of these uncertainties, it is impossible to say whether aldehydes, ketones, or carboxylic acids are the most basic in solution. Gas-phase data are available for some of these substances. 

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