PREPARATION OF ALLYLIC ACETATES FROM SIMPLE ALKENES BY PALLADIUM(II)-CATALYZED ACETOXYLATION

The scope and limitations of palladium-catalyzed allylic acetoxylation of alkenes has been investigated, using benzoquinone—manganese dioxide as the reoxidation system. Unsubstituted cycloalkenes gave good to excellent yields of allylic acetates. Total yields were also good for many substituted cycloalkenes and for linear alkenes, but these substrates generally gave several isomeric acetates. The exploratory mechanistic studies show that the acetoxylation can proceed via both 1,2-acetoxypalladation and η3-allylpalladium complex formation. The keen balance between these processes depends on the structure of the alkene. © 1990, American Chemical Society. All rights reserved.