CHEMOSELECTIVE REMOVAL OF ALLYLIC PROTECTING GROUPS USING WATER-SOLUBLE PD(OAC)(2) TPPTS CATALYST/

The removal of allylic protecting groups promoted by the catalytic sys tem Pd(OAc)(2)/TPPTS has been achieved on bifunctional substrates with complete chemoselectivity and high efficiency, in aqueous media. By l owering the amount of palladium catalyst, substituted allylic carboxyl ates remained unaffected while allylcarbamates, in the same molecule, were quantitatively removed. When using a biphasic C3H7CN-H2O solvent, the water-soluble catalyst could also differentiate allylcarbonates f rom dimethylallylcarbamates on diprotected amino alcohols. All these r eactions were carried out under mild and neutral conditions which are compatible with a large range of molecules including beta-lactams.