Study On The Hydrogenation Of C=O Unsaturated Bond Catalyzed By Nanoporous Palladium

Aromatic alcohols are important organic dyes and pharmaceutical intermediates.The production of aromatic alcohols with high added value through catalytic hydrogenation of aromatic ketones not only conforms to the concept of green chemistry development,but also has high economic value.The nanoporous palladium?PdNPore?catalyst is an excellent heterogeneous catalyst with large specific surface area,high porosity and self-supporting.Simultaneously,it has the unique three-dimensional bicontinuous network structure.Unsupported structure,and recycling,reusability capacity make the PdNPore to be a heterogeneous catalyst with good stability.In this paper,the selective hydrogenation of aromatic ketones to alcohols was achieved by using PdNPore and H₂ as a heterogeneous catalyst and hydrogen source without additives under mild conditions.Through optimizing the temperature,catalyst amount,reaction time,solvent type and H₂ pressure,the optimal reaction conditions were determined:temperature is 30oC,H₂ pressure is 1 atm,solvent is methanol,reaction time is 20 h and the catalyst amount is 5 mol%.Under the optimized conditions,the selective hydrogenation of various ketones proceeded smoothly to afford the corresponding alcohols in 93?99%yields with high selectivities.This protocol shows good functional group tolerance,such as methyl,methoxy and hydroxyl groups.The PdNPore catalyst can be easily recovered and reused 10 times without any loss of catalytic activity.In addition,the stability of the catalyst was further demonstrated by an inductively coupled plasma mass spectrometer?ICP?,which showed that no palladium was leached from PdNPore during hydrogenation.