Novel synthesis of conjugated dienes attached to a quaternary carbon center via Pd(0)-catalyzed deconjugative allylation of alkenylidenemalonates.
Palladium(0)-catalyzed deconjugative allylation of alkenylidenemalonates and alkylidenemalonates was achieved for the first time. Reactions of dimethyl 2-((E)-but-2-enylidene)malonate with various allylic acetates using LHMDS as a base in DMF in the presence of Pd(2)dba(3) (2.5 mol %) and PPh(3) (10 mol %) proceeded at room temperature to give the corresponding alpha-allylation products in good yields in a regio- and stereoselective manner. This reaction can also be used for allylation of dimethyl ethylidenemalonate or dimethyl 2-((E)-pent-2-enylidene)malonate and give the desired alpha-allylation products in good yields.
Sato
Yoshihiro
Y
Graduate School of Pharmaceutical Sciences, Hokkaido University, Sapporo 060-0812, Japan. biyo@pharm.hokudai.ac.jp
Oonishi
Yoshihiro
Y
Mori
Miwako
M