Ketones aryl, from aromatic compounds

Aryl vinyl ketones Electron-rich aromatic compounds undergo electrophilic substitution with EtSCHjCHjCOBF (formed in situ from the acid fluoride and boron trifluoride) at low temperature. The products furnish ArCOCH=CI after methylation followed by treatment with a mild base. 

The Willgerodt reaction is useful in the preparation of arylacetic acids and amides from substituted methyl aryl ketones or vinyl aromatic compounds. The aliphatics and acetylenes give lower yields. The conversion is effected by heating aromatic compounds at 160°-200°C in an aqueous solution under pressure using ammonium polysulfide. In the Kindler modification, the ketone or styrene is refluxed with a mixture of sulfur and an amine, usually morpholine, to give a thioamide, ArCHjCSNRj. 

Carbanions from hydrocarbons, nitriles, ketones, esters, TV./V-dialkyl acetamides and thioamides, and mono and dianions from (3-dicarbonyl compounds are some of the most common nucleophiles through which a new C-C bond can be formed. This C-C bond formation is also achieved by reaction with aromatic alkoxides. Among the nitrogen nucleophiles known to react are amide ions to form anilines however, the anions from aromatic amines, pyrroles, diazoles and triazoles, react with aromatic substrates to afford C-arylation. 

Muratake et al. reported the intramolecular a-arylation of ketones [55,56]. Thus, polycyclic compounds are readily obtained from aromatic keto-bromides and keto-triflates (Eq. 16). Bromo-amides can give the corresponding cycliza-tion products (Eq. 17) [52]. Related intramolecular vinylation reactions to give aliphatic polycyclic compounds have also been reported (Eq. 18) [57,581. The intramolecular cyclization of aromatic halo-ketones under carbon monoxide, which proceeds by mechanism C, gives the corresponding a-acylated products (Eq.l9) [321. 

The Fries rearrangement used for the preparation of aryl ketones from phenolic esters is now one of the most significant reactions in the synthetic chemistry of aromatic compounds, both in the classical version (equation 99) and in the newest modifications (see Section IV.D.3). 

This reaction was initially reported by Dakin in 1909. It is the preparation of phenols from aryl aldehydes or aryl ketones involving the oxidation of corresponding aromatic compounds by hydrogen peroxide in the presence of a base and subsequent hydrolysis of the aryl formate or alkylcarboxylate intermediates. Therefore, this reaction is generally known as the Dakin reaction. It has been reported that the para-or ortho- substituents (such as OH, NH2) on aryl aldehydes or aryl ketones will facilitate this reaction, especially for the ortho OH group, which accelerates the reaction via the formation of an intfamolecular hydrogen bonding. ... 

The arylation of aromatic ketones with arylboronates proceeds by an oriho-ruthenation with RuH2(CO)(PPh3)3 as the catalyst [137]. In this transformation, the final C—C bond is formed in a transmetallation-reductive elimination process. In a different reaction, ortHo-arylated compounds are obtained from o-aminoaryl ketones and arylboronates through substitution of the amino function catalyzed by the same Ru(II) complex [138], A nitrogen-directed homocouphng of aromatic compounds takes place with Ru(II) catalysts in the presence of aUylic chlorides or acetates by a mechanism that presumably involves Ru(IV) intermediates [139],... 

The case of 2,4,6-tris(trifluoromethyl)acetophenone has been discussed in some detail in order to demonstrate that sometimes Rp chemistry can be quite different from that of less sterically hindered aromatic compounds. Similar problems as in the case of RfC(0)CH3 were encountered in an attempted preparation of a related aryl vinyl ketone, RfC(0)CH=CH2 (28), When RfLI was reacted with acryloyl chloride, CH2=CH-C0C1, a mixture of two ketones was obtained. One of them seemed to be RfC 0)CH=CH2, The other ketone, RfC(0)CH2CH2Rf, resulted from a Michael addition between RfC(0)CH=CH2 and the strong nucleophile RfLI (Equation 3),... 

The N,]S -dialkyl-/)-PDAs are manufactured by reductively alkylating -PDA with ketones. Alternatively, these compounds can be prepared from the ketone and -lutroaruline with catalytic hydrogenation. The /V-alkyl-/V-aryl- -PDAs are made by reductively alkylating -nitro-, -nitroso-, or /)-aminodipheny1 amine with ketones. The AijAT-dialkyl- PDAs are made by condensing various anilines with hydroquinone in the presence of an acid catalyst (see Amines-aromatic,phenylenediamines). 

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