Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Aryl-ketones

Tetraphenylethylene Glycol. This prcp iration illustnites the mild conditions under which aryl ketones may undergo bimolecular reduction to com-... [Pg.151]

Claisen-Schmidt reaction. Aromatic aldehydes condense with aliphatic or mixed alkyl-aryl ketones in the presence of aqueous alkali to form ap-unsaturated ketones ... [Pg.709]

In the alkyl aryl ketones, the aryl groups migrate preferentially, yielding V-aryl amides. [Pg.917]

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.) ... [Pg.923]

Another version of the Friedel-Crafts reaction uses acyl halides instead of alkyl halides and yields aryl ketones... [Pg.484]

The most commonly used method for reducing an aryl ketone to an alkylbenzene employs a zinc-mercury amalgam m concentrated hydrochloric acid and is called the Clemmensen reduction Zinc is the reducing agent... [Pg.486]

The preference for O acylation of phenols arises because these reactions are kmetically controlled O acylation is faster than C acylation The C acyl isomers are more stable how ever and it is known that aluminum chloride is a very effective catalyst for the conversion of aryl esters to aryl ketones This isomerization is called the Fries rearrangement... [Pg.1006]

Ketones C=0 continued) o-Amino-aryl or o-hydroxy-aryl ketones 1655-1635 Low because of intramolecular H bonding. [Pg.741]

Synthesis and Properties. Polyquinolines are formed by the step-growth polymerization of o-aminophenyl (aryl) ketone monomers and ketone monomers with alpha hydrogens (mosdy acetophenone derivatives). Both AA—BB and AB-type polyquinolines are known as well as a number of copolymers. Polyquinolines have often been prepared by the Friedlander reaction (88), which involves either an acid- or a base-catalyzed condensation of an (9-amino aromatic aldehyde or ketone with a ketomethylene compound, producing quinoline. Surveys of monomers and their syntheses and properties have beenpubhshed (89—91). [Pg.538]

The wide variety of ketomethylene and amino ketone monomers that could be synthesized, and the abiUty of the quinoline-forming reaction to generate high molar mass polymers under relatively mild conditions, allow the synthesis of a series of polyquinolines with a wide stmctural variety. Thus polyquinolines with a range of chain stiffness from a semirigid chain to rod-like macromolecules have been synthesized. Polyquinolines are most often prepared by solution polymerization of bis(i9-amino aryl ketone) and bis (ketomethylene) monomers, where R = H or C H, in y -cresol with di-y -cresyl phosphate at 135—140°C for a period of 24—48 h (92). [Pg.538]

ARENS VAN DORP Cinnamaldehyde Synthesis Synthesis ol cinnamaldehydes from aryl ketones... [Pg.6]

BORSCHE - BEECH Aromatic Aldehyde Synthesis Synthesis of aromatic aldehydes and of akyl aryl ketones from aldoximes or semcaibazones and aromatic dlazonum salts... [Pg.43]

Synthesis of aryl ketones or aldehydes from aryl tnllates or iodides and organo stannanes in ihe presence of CO and a palladum catalyst... [Pg.368]

Thakar and Subba Rao showed that reductions with diborane give the same result regardless of whether diborane is generated externally or produced internally by the action of NaBH4 and boron trifluoride or aluminum chloride. They found that alicyclic or dialkyl ketones are not reduced beyond the alcohol stage even under drastic conditions however, diaryl ketones are hydrogenolyzed under normal conditions, while aryl ketones or a,i5-unsatu-rated ketones are hydrogenolyzed, in part, under drastic conditions. [Pg.90]

Aryl ketone hydra ones are oxidized and fluonnated by fluorine to give a mixture of mono and difluoro hydrocarbons [74] (equation 10)... [Pg.45]

Aryl halides with a halogen activated by electron-withdrawing groups react with pyrrolidine enamines of cyclic ketones (68) to give the a-arylated ketones after hydrolysis. The enamine (28) with 2,4-dinitrochlorobenzene gave an excellent yield of 2(2,4-dinitrophenyl)cyclohexanone (88). The... [Pg.133]

Low yields of C-arylated ketones have also been obtained by reaction of pyrrolidine enamines with diaryl iodonium salts (68). [Pg.134]

Diaryliodonium salts also reacted with enamines to give a-aryl ketones in low yields (370). [Pg.381]

BF3-Et20, NaCNBHs, THF, reflux 4-24 h, 65-98% yield. Functional groups such aryl ketones and nitro compounds are reduced and electron-rich phenols tend to be alkylated with the released benzyl carbenium ion. The use of BF3 Et20 and triethylsilane as a cation scavenger is also effective." ... [Pg.90]

HSCH2CH2SH, Mgl2, Et20, It, 8 h, 95-96% yield. Aryl ketones are not efficiently protected. [Pg.336]

Depending on the specific reaction conditions, complex 4 as well as acylium ion 5 have been identified as intermediates with a sterically demanding substituent R, and in polar solvents the acylium ion species 5 is formed preferentially. The electrophilic agent 5 reacts with the aromatic substrate, e.g. benzene 1, to give an intermediate cr-complex—the cyclohexadienyl cation 6. By loss of a proton from intermediate 6 the aromatic system is restored, and an arylketone is formed that is coordinated with the carbonyl oxygen to the Lewis acid. Since a Lewis-acid molecule that is coordinated to a product molecule is no longer available to catalyze the acylation reaction, the catalyst has to be employed in equimolar quantity. The product-Lewis acid complex 7 has to be cleaved by a hydrolytic workup in order to isolate the pure aryl ketone 3. [Pg.117]

An analogous reaction is the Houben-Hoesch reaction,(sometimes called the Hoesch reaction) using nitriles 7 to give aryl ketones 8. This reaction also is catalyzed by Lewis acids often zinc chloride or aluminum chloride is used. The Houben-Hoesch reaction is limited to phenols—e.g. resorcinol 6—phenolic ethers and certain electron-rich aromatic heterocycles ... [Pg.134]

The synthetic importance of the Houben-Hoesch reaction is even more limited by the fact that aryl ketones are also available by application of the Friedel-Crafts acylation reaction. [Pg.134]

While the Friedel-Crafts acylation is a general method for the preparation of aryl ketones, and of wide scope, there is no equivalently versatile reaction for the preparation of aryl aldehydes. There are various formylation procedures known, each of limited scope. In addition to the reactions outlined above, there is the Vdsmeier reaction, the Reimer-Tiemann reaction, and the Rieche formylation reaction The latter is the reaction of aromatic compounds with 1,1-dichloromethyl ether as formylating agent in the presence of a Lewis acid catalyst. This procedure has recently gained much importance. [Pg.135]

The Schmidt reaction of ketones works best with aliphatic and alicyclic ketones alkyl aryl ketones and diaryl ketones are considerably less reactive. The reaction is only seldom applied to aldehydes as starting materials. The hydrazoic acid used as reagent is usually prepared in situ by treatment of sodium azide with sulfuric acid. Hydrazoic acid is highly toxic, and can detonate upon contact with hot laboratory equipment. [Pg.253]

Another example is tamoxifen (89). Its synthesis begins with Grignard addition of reagent to aryl ketone giving carbinol Dehydration leads to the readily separable and... [Pg.51]

Quazepam (88) has a highly fluorinated sidechain so as to make this tranquilizer resistant to dealkylation. It also incorporates a lipid-solubilizing 2-thione moiety. The synthesis begins with bi aryl ketone derivative by ] -al kylation with 2,2,2-trifluoroethyltriclate to give 86. [Pg.196]


See other pages where Aryl-ketones is mentioned: [Pg.16]    [Pg.200]    [Pg.486]    [Pg.824]    [Pg.1004]    [Pg.557]    [Pg.412]    [Pg.109]    [Pg.195]    [Pg.466]    [Pg.311]    [Pg.486]    [Pg.824]    [Pg.1004]    [Pg.106]    [Pg.46]    [Pg.193]    [Pg.453]    [Pg.280]    [Pg.252]    [Pg.39]    [Pg.94]   
See also in sourсe #XX -- [ Pg.10 ]

See also in sourсe #XX -- [ Pg.124 ]

See also in sourсe #XX -- [ Pg.86 ]

See also in sourсe #XX -- [ Pg.319 , Pg.440 ]

See also in sourсe #XX -- [ Pg.163 ]

See also in sourсe #XX -- [ Pg.116 ]

See also in sourсe #XX -- [ Pg.15 ]

See also in sourсe #XX -- [ Pg.178 ]

See also in sourсe #XX -- [ Pg.87 ]

See also in sourсe #XX -- [ Pg.87 ]

See also in sourсe #XX -- [ Pg.178 ]

See also in sourсe #XX -- [ Pg.50 , Pg.56 , Pg.66 , Pg.96 ]

See also in sourсe #XX -- [ Pg.55 , Pg.102 , Pg.129 ]

See also in sourсe #XX -- [ Pg.98 , Pg.490 ]

See also in sourсe #XX -- [ Pg.138 ]

See also in sourсe #XX -- [ Pg.5 , Pg.31 , Pg.604 ]

See also in sourсe #XX -- [ Pg.154 ]




SEARCH



A-Aryl methyl ketones

Alcohols, aryl => ketones

Alkenyl aryl ketones

Alkyl aryl ketones

Alkyl aryl ketones, synthesis

Alkyl-aryl ketone arylation

Alkylbenzene, biological oxidation from aryl alkyl ketones

Amides from aryl ketones

Arene from aryl alkyl ketones

Aromatic compounds aryl ketones

Aryl aliphatic ketones, reactions

Aryl alkene ketone

Aryl alkyl ketone, reduction

Aryl alkyl ketones irradiation

Aryl alkyl ketones reductive amination

Aryl alkyl ketones, oxidation

Aryl cyclopropyl ketones

Aryl derivatives ketone arylation

Aryl derivatives ketones

Aryl derivs. (s. a. Arenes ketone synthesis

Aryl ether ketone copolymers

Aryl ether ketone oligomers

Aryl ethynyl ketone

Aryl halides ketones)

Aryl heteroaryl ketones

Aryl ketone hydrazones, reaction

Aryl ketones amides

Aryl ketones and esters

Aryl ketones hydrogenation

Aryl ketones hydrogenolysis

Aryl ketones selectivity

Aryl ketones stannanes, carbonylation

Aryl ketones stereospecific

Aryl ketones trifluoromethanesulfonic anhydride

Aryl ketones, Meerwein-POnndorf-Verley

Aryl ketones, Meerwein-POnndorf-Verley reduction

Aryl ketones, by Friedel-Crafts acylation

Aryl ketones, cyclodehydration

Aryl ketones, pinacol coupling

Aryl ketones, reductive coupling

Aryl ketones, silane reduction

Aryl methyl ketone chiral acetal

Aryl methyl ketones

Aryl methyl ketones migration

Aryl trifluoromethyl ketones

Aryl trifluoromethyl ketones reduction

Aryl vinyl ketones

Aryl vinyl ketones, Michael reactions

Aryl-ketone stabilizing interaction

Aryl/alkyl ketones hydrogenation

Aryl/alkyl ketones hydrosilylation

Aryl/alkyl ketones transfer hydrogenation

Aryl/heteroaryl, diaryl ketones

Arylacetic acid esters aryl methyl ketones

Arylation of Ketones and Aldehydes

Arylation of hindered ketones

Arylation of ketones

Arylations of Ketones

Asymmetric aryl alkene with chiral ketone

Asymmetric aryl ketones

Asymmetric synthesis ketone arylation

Claisen condensation, aryl/alkyl ketone

Cross-coupling reactions ketone arylation

Cyanoacetates aryl vinyl ketones

Cyclic aryl ketones yields

Cyclic ketones 2-arylated

Cycloaddition of aryl cyclopropyl ketones

Dialkyl and aryl-alkyl ketones

Enantioselective Arylation of Aryl-Alkyl-Substituted Ketones

Friedel-Crafts acylation aryl ketones

Halomethyl aryl ketones

Heck coupling reactions ketone enolate arylation

Hydrosilylation of aryl/alkyl ketones

Imines derived from aryl/alkyl ketones

Intermolecular reactions ketone arylation

Ketone alkyl aryl ketones

Ketone aryl bromides

Ketone aryl chlorides

Ketone arylation NHCs)

Ketone arylation catalytic system

Ketone arylation conditions

Ketone arylation intermediate

Ketone arylation versions

Ketones 2-aryl-5- oxazoles

Ketones alpha-arylation

Ketones aryl, acetylenic

Ketones aryl, from aromatic compounds

Ketones aryl, from nitriles

Ketones aryl, oxidation

Ketones aryl, rearrangement

Ketones aryl-pyridyl

Ketones arylation

Ketones arylation

Ketones arylation enantioselective

Ketones arylation reactions

Ketones asymmetric arylation

Ketones photochemical arylation

Ketones prochiral aryl alkyl

Ketones, 2-arylated

Ketones, 2-arylated Friedel-Crafts reaction

Ketones, 2-arylated synthesis

Ketones, 2-haloalkyl aryl

Ketones, 2-haloalkyl aryl ketals

Ketones, 2-haloalkyl aryl rearrangement

Ketones, a-aryl

Ketones, a-aryl via SrnI reaction

Ketones, a-arylation

Ketones, aryl alkyl Baeyer-Villiger reaction

Ketones, aryl hydride transfer

Ketones, aryl methyl carbonylation

Ketones, aryl methyl synthesis

Ketones, aryl oxidative rearrangement

Ketones, aryl reduction

Ketones, aryl synthesis

Ketones, aryl via rearrangement of arylalkenes

Ketones, vinyl arylation

Ketones, with Aryl aliphatic

Ketones, y-aryl-a-trifluoromethyl Friedel-Crafts reaction

Methyl-aryl ketones, aldol reactions

Microwave irradiation, aryl ketones

Oximes of Alkyl Aryl Ketones

Phenols from aryl ketones

Poly(Aryl Ether Ketone) Based Blends

Poly(aryl ether ketone

Poly(aryl ether ketone)s

Preparation of Aryl Ketones via Ni-Catalyzed Negishi Coupling Reactions

Reaction XIV.—(a) Action of Magnesium Alkyl or Aryl Halide on Aldehydes and Ketones (Grignard)

Reduction of Aryl Ketones

Rhodium ketone arylation

Similarity trifluoromethyl aryl ketones

Sodium borohydride ketones, aryl

Some reactions of alkyl aryl ketones

Synthesis and Characterization of Poly (aryl ether ketone) Copolymers

Synthesis and Characterization of Poly (aryl ether ketone) Copolymers with Pendent Group

Synthesis of Aryl Ketones and Amidines

The Photoreduction of Aryl Ketones Structural Aspects

Transition metal catalysts ketone arylation

Y-Arylated ketones

Zeolites alkyl aryl ketones

© 2024 chempedia.info