Practical Palladium-Mediated Deprotective Method of Allyloxycarbonyl Groups in Aqueous Media
The Allyloxycarbonyl (Alloc) moiety can be removed smoothly and selectively in good yield (73-100%) from allylic eaters, carbamates and carbonates by aqueous Pd (0) catalyzed allyl transfer to diethylamine in aqueous media employing a water soluble phosphine. The allyl scavenger as well as by product allyl diethylamine are volatile and easily removed in vacuo. In a two phase system an increased selectivity is seen. The method has been successfully used for deprotection of a wide range of secondary amines or base sensitive derivatives and the catalyst is efficiently recycled.