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Ketones by Friedel-crafts acylation

For the synthesis of isoindoles (benzo[c]pyrroles) by type la cyclization the required intermediate is an o -acylbenzylamine. The only viable route to these substances which has been developed starts with a -bromo-o -toluic acid which is converted first to a phthalimide and then to the acid chloride. The acid chloride is then elaborated to the requisite ketone by Friedel-Crafts acylation. Condensation to the isoindole occurs on liberation of the primary amino group using hydrazine (equation 18) (64JA4152). [Pg.319]

Recalling that arylamines are normally prepared by reduction of nitroarenes, we see that ethyl m-nitrophenyl ketone is a pivotal synthetic intermediate. It is prepared by nitration of ethyl phenyl ketone, which is analogous to nitration of acetophenone, shown in Section 12.16. The preparation of ethyl phenyl ketone by Friedel-Crafts acylation of benzene is shown in Section 12.7. [Pg.613]

Different patents have been registered concerning the preparation of specific aryl ketones by Friedel-Crafts acylation of convenient aromatic substrates in the presence of variable amounts of both Bronsted and Lewis acids. As an example, a large number of aryl ketones was efficiently synthesized through acylation of arenes with acyl chlorides in methylene chloride and in the presence of a mixture of aluminum chloride and lithium chloride as the catalyst. Some synthetic results are reported in Table 2.3. [Pg.15]

Finally, Section 15-13 discussed the synthesis of aryl ketones by Friedel-Crafts acylation, a form of electrophilic aromatic substitution. The following example furnishes an industrially... [Pg.749]

A closet member of this little group, revelation of whose i(>al nature requires metabolic transformation of an acetylenic linkage to an acetic acid moiety, is fl uretofen (14). The .ynthesis begins by Friedel-Crafts acylation of 2-fluorobi-phenyl (11) with acetic acid to give ketone 1. Heating with... [Pg.39]

I Aryl ketones are prepared by Friedel-Crafts acylation of an aromatic ring with an acid chloride in the presence of AICI3 catalyst (Section 16.3). [Pg.700]

Furyl ketones can be easily obtained by Friedel-Crafts acylation of furans. They can also be obtained from derivatives of furan-2-carboxylic acid such as the amides, nitriles and chlorides by literature reactions. The 3-furyl ketones are also obtained by similar methods. [Pg.711]

Formaldehyde, acetaldehyde, and acetone are important commercial chemicals, synthesized by special methods. In the laboratory, aldehydes and ketones are most commonly prepared by oxidizing alcohols, but they can also be prepared by hydrating alkynes and by Friedel-Crafts acylation of arenes. Aldehydes and ketones occur widely in nature (see Figure 9.1). [Pg.157]

In 1962, Bonner (14) at DuPont was the first one who reported the synthesis of wholly aromatic poly(ether ketone ketone)s (PEKK) by Friedel-Crafts acylation. Isophthaloyl chloride was condensed with diphenyl ether using nitrobenzene as solvent and aluminum trichloride as a catalyst. [Pg.283]

Most of the reactions of the phenothiazinyl ketones discussed here were carried out on compounds of the 2 series readily available by Friedel-Crafts acylation (See Section V,A,4,c) many products derived from these ketones are of pharmacological importance. [Pg.441]

The procedure described here is typical for the catalytic alkylation of aromatic ketones at the ortho position by alkenes. Aromatic ketones are readily available by Friedel-Crafts acylation and many other methods, and many of these ketones are suitable substrates for the present catalytic alkylation with alkenes affording the corresponding ortho-alkylated ketones. The present method provides a direct way to alkylate aromatics with olefins. Moreover, the C-C bond formation takes place with exclusive ortho selectivity, while mixtures of 0-, m-, p-isomers are usually obtained in the conventional Friedel-Crafts alkylation of aromatic compounds. [Pg.42]

Vinylsilanes (8, 491-492) aHylic alcohols (9, 340). Details are available for conversion of a ketone to a vinylsilane in which the C—Si bond has replaced the C==0 group (enesilylation). The reaction affords the less substituted vinylsilane in the case of unsymmetrical ketones. The paper includes details for use of vinylsilanes for cyclopentenone annelation by Friedel-Crafts acylation with acryloyl chlorides and subsequent cyclization of penladienyl cations (9,498-499).1... [Pg.52]

Preparation. Odom and Pinder1 recommend preparation of the reagent by Friedel-Crafts acylation of propylene with acetyl chloride to give 2-chloropropyl methyl ketone, which is then dehydrochlorinated to give the reagent. The pro-... [Pg.112]

Most of the 2-benzopyrylium salts that have been synthesised subsequently are 1,3-disubstituted and their precursors prepared by Friedel-Crafts acylation of activated benzyl ketones. " ... [Pg.242]

Pillai developed the 2 -nitrobenzhydryl PS resin [20] (8, NBH resin) as an a-substituted nitrobenzyl Hnker. The NBH resin was prepared from o-nitrobenzoyl chloride and 1% cross-Hnked PS resin by Friedel-Crafts acylation and ketone reduction (Scheme 17.7). Photolysis of single amino acids from the NBH resin... [Pg.474]

Synthesis from anisole and propionic acid derivatives. Anisole is converted into 4-methoxypropiophenone by Friedel-Crafts acylation with propionyl chloride or propionic anhydride. The ketone is hydrogenated to the corresponding alcohol with a copper chromite catalyst. The alcohol is dehydrated in the presence of acidic catalysts to a cis/trans mixture of anetholes [163b]. [Pg.135]

Acid-catalyzed cyclization of ketone 6, obtained by Friedel-Crafts acylation of Af-acety 1-tryptamine with 2-cyclohexyl acetyl chloride (45 to 50%)... [Pg.107]


See other pages where Ketones by Friedel-crafts acylation is mentioned: [Pg.677]    [Pg.625]    [Pg.625]    [Pg.627]    [Pg.625]    [Pg.625]    [Pg.627]    [Pg.677]    [Pg.677]    [Pg.625]    [Pg.625]    [Pg.627]    [Pg.625]    [Pg.625]    [Pg.627]    [Pg.677]    [Pg.94]    [Pg.580]    [Pg.332]    [Pg.47]    [Pg.87]    [Pg.1088]    [Pg.331]    [Pg.517]    [Pg.38]    [Pg.35]    [Pg.283]    [Pg.624]    [Pg.626]    [Pg.646]   
See also in sourсe #XX -- [ Pg.1678 ]

See also in sourсe #XX -- [ Pg.623 ]

See also in sourсe #XX -- [ Pg.623 ]




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Acylic ketones

Aryl ketones, by Friedel-Crafts acylation

Friedel acylation

Friedel-Crafts ketone

Ketones acylation

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