Palladium-catalyzed Heck reaction on 1-alkoxy-1,3-dienes: a regioselective gamma-arylation of alpha,beta-unsaturated carbonyl compounds.
[reaction: see text] alpha,beta-Unsaturated acetals afford, in the presence of the LIC-KOR superbase, 1-alkoxybuta-1,3-dienes. These substrates cross couple with aryl derivatives in the presence of Pd catalyst (Heck conditions) in a regio- and stereoselective mode. With dialkyl acetals, the reaction affords arylated dienes; on the other hand, in the case of 1,3-dioxane derivatives, the final outcome of the process formally corresponds to the direct gamma-arylation reaction of the starting alpha,beta-unsaturated material.
Deagostino
Annamaria
A
Dipartimento di Chimica Generale ed Organica Applicata dell'Università, Corso Massimo D'Azeglio, 48, I 10125 Torino, Italy.
Prandi
Cristina
C
Venturello
Paolo
P