Cyclohexadiene, 1,4-, hydrogen donor transfer hydrogenolysis

Deprotection takes place by catalytic hydrogenation in the presence of palladium under a hydrogen pressure of a few atmospheres. This reforms the hydroxyl groups and toluene is easily separated. Hydrogenolysis by transfer does not require any special equipment. An alcohol solution is heated at reflux with the protected sugar in the presence of palladium over charcoal with, as hydrogen donor, cyclohexene or cyclohexadiene which aromatizes in the reaction. 

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