80331-29-9Relevant academic research and scientific papers
CONJUGATE ADDITION VS. VINYLIC SUBSTITUTION IN PALLADIUM-CATALYSED REACTION OF ARYL HALIDES WITH β-SUBSTITUTED-α,β-ENONES AND -ENALS
Amorese, A.,Arcadi, A.,Bernocchi, E.,Cacchi, S.,Cerrini, S.,et al.
, p. 813 - 828 (2007/10/02)
The reaction of β-substituted-α,β-enones and -enals with aryl halides in the presence of a palladium catalyst has been investigated.The outcome of the reaction was found to be greatly dependent on the nature of the added base.Tertiary amines tend to favour the formation of conjugate addition-type products while sodium bicarbonate or sodium acetate that of vinylic substitution products.Usually, the use of sodium acetate produced results comparable or better than those obtained with sodium bicarbonate.Furthermore, in the reaction of aryl halides containing strongly electron-withdrawing groups, sodium acetate afforded a dramatic increase in the yield of vinylic substitution products.
Palladium-Catalyzed Conjugate Addition Type Reaction of Aryl Iodides with α,β-Unsaturated Ketones
Cacchi, S.,Arcadi, A.
, p. 4236 - 4240 (2007/10/02)
Aryl iodides have been found to react with α,β-unsaturated ketones in the presence of catalytic amounts of palladium, an excess of formic acid, and triethylamine, giving rise to conjugate addition type products.The electron-withdrawing power of the group attached to the olefinic double bond, the substituent β to the carbonyl group, and the basic reaction medium appear to effect greatly the conjugate addition/vinylic substitution ratio.
THE PALLADIUM-CATALYSED CONJUGATE ADDITION TYPE REACTION OF ARYLMERCURY COMPOUNDS WITH α,β-UNSATURATED KETONES IN A TWO-PHASE SYSTEM
Cacchi, S.,Misiti, D.
, p. 2941 - 2946 (2007/10/02)
Pd-catalysed reaction of arylmercury compounds with α,β-enones in an acidic two-phase system provides a mild and selective way to β-aryl ketones.The present conjugate addition type reaction may accomodate a wide variety of functional groups.Thus, aryl units containing electron-donating and electron-withdrawing substituents such as -Me, -Cl, -CHO, -COMe, -COOMe, -COOH, -OH, -OMe, -NHCOMe and NO2 were succesfully transfered to the β C atom of benzalacetone.A number of α,β-enones were also treated with 3-formylphenyl mercury chloride to give the corresponding β-(3-formylphenyl) derivatives.The main limitation seems to arise from steric hindrance in the starting α,β-enonic system.Substituents in the aryl moiety of the organomercury compounds were found to affect the transmetalation steps in the direction expected for a rate determining ?-complex formation.
