P- acetophenone

Fig 23(A) shows an assembly for boiling a liquid under reflux whilst adding another liquid at a rate which can be clearly seen cf. preparation of acetophenone, p. 253). The outlet A allows expansion of the vapour content, and can be fitted with a calcium chloride or soda-lime tube. The outlet A can also be used for collecting a gas evolved during the reaction cf, preparation of acetylene,... 

The preparation of acetophenone (p. 255) is a modification of this method, the alkyl halide being replaced by an acid chloride, with the consequent formation of a ketone. 

The Fischer Indolisation Reaction occurs when the phenylhydrazone of a suitable aldehyde or ketone undergoes cyclisation with loss of ammonia, under the influence of various reagents, such as zinc chloride, ethnnolic hydrogen chloride, or acetic acid. For example, the phenylhydrazone of acetophenone (p. 257) when heated with zinc chloride gives 2 phenylindole. ... 

A number of recommendations have been made in the development of quantitative chromatographic methods. The American Society for Testing Materials — using as a benchmark the reversed phase separation of benzyl alcohol, acetophenone, benzaldehyde, benzene, and dimethylterephthalate — discovered substantial laboratory-to-laboratory differences in quantitative analysis.53 These compounds are routinely used to test column performance or for system suitability testing. A followup study, using benzyl alcohol, acetophenone, p-tolualdehyde, and anisole, showed that measurement of... 

Often in the Friedel-Crafts synthesis the acid chloride can be replaced by the anhydride. The preparation of acetophenone (p. 346) is an example of this modification. 

IR spectra of substituted acetophenones, p-XC6H4COMe, in chloroform suggest the presence of hydrogen-bonded dimers for X = H and NO2, but not OMe ° such association may play a role in keto-enol tautomerization. 

A variety of aliphatic and aromatic ketones have been investigated (cyclohexanone, cyclopentanone, acetophenone, p-nitroacetophenone) and they all usually lead to 2-R -3-R"-5-nitropyridine in moderate to good yields. Better yields were recorded when enamines of the respective ketones were used. With aldehydes the yields are in general lower than with ketones. 

Similar decomposition is observed in p-bromoacetophenone, o-bromo-, p-bromo, and p,p -dibromobenzophenone, and p-iodobenzophenone44 but not in the fluoro- and chloro-substituted compounds. This order of reactivity follows the bond dissociation energies for aromatic halides which are about 90 kcal/mole for chlorobenzene, 70 kcal/mole for bromobenzene, and 60 kcal/ mole for iodobenzene. The lowest-lying triplet of p-bromoacetophenone is 71.2 kcal45 while that of the substituted benzophenones is slightly lower since benzophenone itself has a lower triplet energy than acetophenone. p,p Dibromobenzophenone was the least reactive of the compounds that photoeliminated halogen atoms. 

The following couples were tested p-chlorobenzonitrile/p-chloro-acetophenone, p-chloroacetophenone/p-chlorodiphenyl, p-chlorodiphenyl /chlorobenzene, p-chlorodiphenyl/p-chlorofluorobenzene, chlorobenzene /p-chlorotoluene, chlorobenzene/p-chloroanisole, p-chloroacetophenone/ methyl ester of m-chlorobenzoic acid, chlorobenzene/m-chlorotoluene, p-chlorodiphenylether/p-chlorotoluene, m-chlorodiphenylether/chloroben-zene, m-chlorodiphenylether/p-chlorotoluene, chlorobenzene/methyl ester of m-chlorobenzoic acid, chlorobenzene/p-bromoanisole, p-bromoaceto-phenone / p-chlorobenzonitrile, p-bromobenzonitrile / p-chloroacetophe-none, bromobenzene/p-chlorodiphenyl, m-bromotoluene/chlorobenzene, and p-chlorodiphenyl/p-bromotoluene. 

PA, phenyl acetate o-HAP, o-hydroxy acetophenone p-HAP, p-hydroxy acetophenone PH, phenol CA, catechol HQ, hydroquinone AA, acetic acid. 

SYNS CHALCONE, 4-METHYL-(6CI,7CI,8CI) (4-METHYLBENZYLIDENE)ACETOPHENONE p-METHYLCHALCONE 3-(4-METHYLPHENYL)-l-PHENYL-2-PROPEN-1-ONE PHENYL p-METHYLSTYRYL KETONE 2-PROPEN-l-ONE,3-(4-METHYLPHENYL)-1-PHENYI ... 

Acetophenone-p-arsinic acid, CH3.CO.C61T. AjsO(OH)2 (see also below), is obtaincil irom p-amino-acetophenone by diazotisation and treatment with sodium arscnite (Bart s reaction). Tlie acid is insoluble in water, but soluble in alkalis or glacial acetic acid. 

Hydrazmopyridine-5-arsinio acid, 543. l-Hydroxy-2-acetophenone-p-ajsinio acid, 335. 

The oxidation of methyl ketones to a-keto carboxylic acids is rare and is accomplished by treatment with a cold solution of potassium permanganate. However, the reaction is not general acetophenone, p-methyl-acetophenone, and 3,4-dimethylacetophenone are oxidized all the way to the corresponding benzoic acids. On the other hand, 2,4-dimethylaceto-phenone, when shaken with approximately 1% aqueous potassium permanganate at room temperature, gives 6 72% yields of 2,4-dimethyl-phenylglyoxylic acid [555, 559],... 

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