There have been reported a number of palladium-catalyzed reactions which proceed by way of a-allylpalladium intermediates. 1 Tsuji and coworkers have developed the allylation of carbonucleophiles by use of ally1 carbonates2 and carbamates3 as effective allylating agents. Here we report a new type of palladium-catalyzed cyclization where 2-butenylene dicarbamates give 4-vinyl-2-oxazolidones in high yields. Dicarbamates 1 were readily obtained by treatment ...