[GRAPHICS]
Reactions of steroidal alpha,beta-epoxy vinyl triflates in Pd-catalyzed rea
ctions are described. Oxidative insertion of Pd-0 into the C-O bond, giving
vinylpalladium 12, is faster than formation of the pi-allyl derivative fro
m the vinyl epoxide. Although 12 can be trapped under certain conditions, i
t eventually rearranges to palladium alkoxide 14, which is in equilibrium w
ith 15 and/or 10.