Palladium-catalyzed Exchange of Allylic Groups of Ethers and Esters with Active Hydrogen Compounds. II.

Abstract

The allylic compounds (I), R1–O–R (R=allylic groups, R1=Ph, Me, PhCH2, MeCO), react with active-hydrogen compounds such as phenols, alcohols, carboxylic acids, primary and secondary amines and active methylene compounds, to give allylic derivatives of the active-hydrogen compounds by an intermolecular exchange of the allylic groups of I with the atom to which the active hydrogens are bonded in the presence of palladium catalysts. Allyl and substituted-allyl ethers are more reactive than the corresponding carboxylates. In the reactions of methyl and benzyl ethers, it is necessary to add phenol to obtain the exchange products in fairly good yields. Bis(triphenylphosphine) palladium chloride plus sodium phenoxide, palladium acetate plus triphenylphosphine, and zerovalent palladium complexes such as tetrakis (triphenylphosphine) palladium and (maleic anhydride)bis(triphenylphosphine)palladium are effective catalysts.