Yoshito Terao

PALLADIUM-CATALYZED MULTIPLE ARYLATION OF PHENYL KETONES WITH ARYL BROMIDES

Abstract Benzyl phenyl ketones undergo triarylation upon treatment with excess aryl bromides in the presence of a catalytic amount of ce:simple-parad(PPh 3 ) 4 and Cs 2 CO 3 as base in o -xylene on the α- and two ortho -positions of the carbonyl group to give diphenymethyl 2,6-diphenylphenyl ketone derivatives as the predominant products. Acetophenone and diphenylmethyl phenyl ketone similarly undergo tetra- and diarylations, respectively.

Multiple arylation of alkyl aryl ketones and α,β-unsaturated carbonyl compounds via palladium catalysis

Abstract Alkyl (ethyl to butyl) aryl ketones have been found to undergo multiple arylation on the alkyl chains accompanied by oxidative unsaturation upon treatment with excess aryl bromides in the presence of a palladium catalyst and a base. In the case of phenyl propyl ketones, for example, the arylation occurs up to five times on the α-and γ-positions as well as the ortho -position of the phenyl ring to give 1-(biphenyl-2-yl)-2,4,4,4-tetraphenyl-2-buten-1-ones along with other arylation products. A number of α,β-unsaturated carbonyl compounds are also arylated multiply on the α- and γ-positions.

Palladium-catalyzed α-arylation of aldehydes with aryl bromides

Aliphatic linear and α-branched aldehydes efficiently undergo arylation at the α-position upon treatment with aryl bromides using an appropriate palladium catalyst system that is capable of overcoming aldol condensation of the substrates.

Regioselective arylation on the γ-position of α,β-unsaturated carbonyl compounds with aryl bromides by palladium catalysis

Abstract Arylation of 2-substituted 2-alkenals and 3-substituted 2-cyclohexen- and 2-cyclopenten-1-ones can effectively and regioselectively proceed at their γ-position by treatment with aryl bromides in the presence of a palladium catalyst and a base.

Palladium-Catalyzed Annulation Reaction of o-Bromobenzaldehydes with Carbonyl Compounds to Produce Naphthol and/or Naphthalene Derivatives

Abstract o-Bromobenzaldehydes undergo annulation with 1,3-diaryl-2-propanones in the presence of a palladium catalyst to give the corresponding 1,3-diaryl-2-naphthols in fair to good yields. From the reaction of the aldehydes with 2-substituted 2-alkenals are formed 2,4-disubstituted 1-naphthols and/or 1,3-disubstituted naphthalenes accompanied by decarbonylation.

Palladium-catalyzed cross-carbonylation of phenolic compounds with aldehydes to give benzofuran-2(3H)-one derivatives

Palladium-catalyzed cross-carbonylation of naphthols and phenols having appropriate substituents with aldehydes in the presence of CF3COOH as a cocatalyst gives the corresponding benzofuran-2(3H)-one derivatives. Under similar conditions, cyclocarbonylation reaction of 2-hydroxybenzyl alcohols also takes place effectively.