Α-arylation Of Ketones Research Articles

Studies on the synthesis of 8-alkyl-8-aryl-2-azabicyclo[3.3.1]nonan-7-ones. A short synthetic route to functionalized 8-alkyl derivatives

Two approaches to 8-alkyl-8-aryl-2-azabicyclo[3.3.1]nonan-7-ones are explored. They are based on the cyclization of an α-alkyl α-aryl ketone upon an iminium salt generated from 2-cyanopiperidine 13 and on the arylation of 8-alkyl-2-azabicyclo[3.3.1]nonan-7-one 20. An efficient, short synthetic route to 8-alkyl-2-azabicyclo[3.3.1]nonan-7-ones, using phosphonate 16 as a 5-functionalized 2-oxopentyl synthon, is reported.

Efficient methodology for the preparation of β-aminotetralin derivatives via electrophilic amination

A mild and efficient method for the construction of β-aryl amines from the corresponding α-aryl ketones is presented. The key steps of the synthesis involve an electrophilic amination by dibenzyl azodicarboxylate followed by a stereoselective LiHBEt3 reduction. The reaction sequence is applied to the synthesis of the tricyclic ergoline analogue 4.

The Formation of Ketones by a Reaction Equivalent to R-+R′COCH2+→R′COCH2R

A general method has been developed for the overall transformation of α- bromo ketones to α-alkyl or α-aryl ketones , with benzotriazole being used as a synthetic auxiliary. α- Benzotriazolyl ketones , when converted into their phenylhydrazones, reacted smoothly with alkyl and aryl Grignard reagents, which displaced benzotriazolate, to give the corresponding α-alkyl or α-aryl hydrazones. In some cases, these hydrolysed directly to the α-alkyl or α-aryl ketones. In each case, the product was treated with 2,4-dinitrophenylhydrazine to isolate the target ketones as the corresponding 2,4-dinitrophenylhydrazones.

Highly Selective Methods for α-Alkenylation and α-Arylation of Ketones via Palladium- or Nickel-Catalyzed Cross Coupling

Abstract Two procedures for α-alkenylation and α-arylation of ketones, that permit, for the first time, introduction of a stereo-defined alkenyl group (E or Z) in the α-position of cyclic ketones in high yields with essentially complete retention (>98%) of the alkenyl stereochemistry are reported. Furthermore, the one that is represented by Eq.2 permits complete control of regiochemistry as well.

ChemInform Abstract: α‐Arylation of Ketones via the Reaction of Silyl Enol Ethers with Arenediazonium Salts.

The reaction of the silyl enol ethers of aryl ketones with arenediazonium salts gives α-arylated ketones in good yields under mild conditions.

α-Arylation of ketones via the reaction of silyl enol ethers with arenediazonium salts

The reaction of the silyl enol ethers of aryl ketones with arenediazonium salts gives α-arylated ketones in good yields under mild conditions.

ChemInform Abstract: THE CHEMISTRY OF ARYLLEAD(IV) TRICARBOXYLATES. REACTION WITH α‐HYDROXYMETHYLENE KETONES: A ROUTE TO α‐ARYLATED KETONES

AbstractDie α‐Hydroxymethylen‐Ketone (I) reagierenmit den entsprechenden Aryl‐Pb‐triacetaten unter Bildung von unbeständigen α‐Aryl‐formyl‐Ketonen, die zu den α‐AryI‐Ketonen (II) hydrolysiert werden [aus (I) (R: ‐tBu) und p‐Tolyl‐Pb‐triacetat erhält man unter den Bedingungen (A) das Diaryl‐ Derivat (III) und nur bei 20°C (Bedingung B) das entsprechende (IIb) (Ausb. 41%)].

The chemistry of aryllead(IV) tricarboxylates. Reaction with α-hydroxymethylene ketones : a route to α-arylated ketones

α-Hydroxymethylene ketones have been shown to react with aryllead triacetates in tetrahydrofuran containing pyridine to give α-aryl α-formyl ketones, unstable compounds, which were hydrolysed directly with alkali to α-aryl ketones. The procedure has been used to produce in good yield 2-(p-methoxyphenyl)cyclohexanone, 2-(p-tolyl)cyclohexanone and the corresponding derivatives of4-t-butylcyclohexanone, and 2α-(p-methoxypheny1)-5α-cholestan-3-one and 3β-hydroxy-16α-(pmethoxypheny1)-5α-androstan-17-one.

The chemistry of aryllead(IV) tricarboxylates. Reaction with β-keto esters: a convenient route to α-arylated ketones

Ethyl 2-oxocyclopentanecarboxylate (1a) and p-methoxyphenyllead triacetate (2a) react in chloroformcontaining pyridine to give ethyl 1-(p-methoxyphenyl)-2-oxocyclopentanecarboxylate (1b) in almost quantitative yield. This arylation reaction of β-keto esters has been examined with a variety of substrates and a number of aryllead triacetates and in all but one case in which the keto ester contained only one α-hydrogen the α-arylated β-keto ester was obtained in excellent yield. With ethyl acetoacetate both mono- and di-arylated products were obtained and yields were somewhat lower.