Study Of The Catalysts Of Pd Supported On Active Carbon For Heterogeous Heck Reaction Systems

Heck reaction is particularly valuable for C-C bond formation in organic synthesis because it does not affect many functional groups such as–OH, -OR, -CO, -COOR, etc. and is highly regioselective and steroselective. More attention is paid to it for it is well applied in synthesis and configuration change of natural products and has much prospect in fine chemicals and polymer industrial. Homogeneous palladium complex suffers from some drawbacks: difficult separating catalyst from product, recycling catalyst, instability of palladium complex at high temperature and high cost. In principle, the use of heterogeneous catalyst could help in solving those problems which have prevented the technical applications of the Heck reaction so far.With high surface area, active carbon has strong adsorbing tendecy to Pd and is in favor of Pd redeposition on it, which decreases losing of precious Pd. The palladium catalysts supported on active carbon were prepared for heterogeneous Heck coupling, and the influence of chemical characters and surface structures of active carbon, components and preparation process on the catalytic activity of the catalysts was investigated. Basing on these experimental results, we discussed and suggested a mechanism of heterogeneous catalysis in Heck reaction.1 Influence of chemical character and surface structure on properties of catalysts...