A Dramatic Effect of the Reaction Conditions on the Course of a Palladium-Catalyzed Cyclization of an Alkene Bearing a Vinyl Bromide and a Nucleophile: A New Route to the trans-Hydrindane System
31 December 2000 (online)
Upon treatment with catalytic Pd(dppe) in the presence of KH, the malonate derivative 3 underwent a Wacker-type cyclization leading exclusively to compound 4 having the trans-hydrindane system. However, the course of the cyclization is dramatically dependent on the reaction conditions, mainly on the nature of the base. In the presence of a carbonate, a quaternary ammonium salt and the catalytic system (Pd(OAc)2 + PPh3) the cyclization of the same substrate 3 led only to compounds resulting from an initial Heck reaction of the vinyl bromide on the neighbouring olefin.
Wacker-type reaction - Heck reaction - palladium - trans-hydrindane - biquinane