The Reaction of Alkenylboranes with Palladium Acetate. Stereoselective Synthesis of Olefinic Derivatives

Article abstract of DOI:10.1246/bcsj.53.1670

The reactions of alkenylboranes with palladium acetate were investigated.Alkenyldialkylboranes, derived from terminal alkynes, underwent intramolecular migration reaction in the presence of an equimolar amount of palladium acetate and triethylamine to give (E)-olefins.On the other hand, under the same conditions as above or even in the presence of catalytic amounts of palladium acetate, alkenyldialkylboranes derived from internal alkynes underwent protonolysis reaction to produce (Z)-olefins.An alkenylpalladium intermediate which was presumably involved in the latter reaction was trapped by allylic chloride to give 1,4-dienes.