Catalytic hydrogenation for the industrial synthesis of the Wong’s anthracyclines intermediate

A new catalytic synthesis of the Wong’s antracyclines intermediate, (R)-2-acetyl-2-hydroxy-5,8-dimethoxy-1,2,3,4-tetrahydronapthlene, starting from the corresponding 1,2-diol has been discovered through its selective hydrogenolysis in the presence of palladium heterogeneous catalysts. High yield and no racemization were found under mild reaction conditions: the molar selectivity towards the target product was always higher than 99.5%. The catalytic performances resulted strongly dependent on the nature of the palladium catalyst, unreduced Pd/C showing the best performances. This straightforward catalytic route significantly improves the up to now adopted industrial process.