Summary: | 碩士 === 國立臺北科技大學 === 分子科學與工程系有機高分子碩士班 === 107 === Aromatic amines are vital precursors in the synthesis of dyes, pigments, agrochemicals, polymers, herbicides, and pharmaceuticals. Much attention has been paid to the synthesis methods because of their wide applications. Traditionally, aromatic nitro group reductions are carried out by catalytic hydrogenations in the presence of metal catalysts, such as Palladium on carbon, Platinum oxide or Raney Nickel. However, due to the flammability of hydrogen which may cause hazardous explosion, many groups tried to seek safer and economical catalytic systems for reduction of nitro group in the past decade. For example, porous nanostructured catalyst can be prepared by adding metal catalyst and supporting material in sequential thermal pyrolysis procedure in high temperature and Oxygen-free atmosphere to reduce the used amount of catalyst and shorten the reaction time. On the other hand, conducting analogous reaction in water and reusing the catalyst is rarely mentioned in published literature.
Thus, we developed a FeCl3·6H2O/cationic 2,2’-bipyridyl aqueous catalytic system using hydrazine monohydrate as reducing agent for reduction of nitroarenes and successfully synthesized various amine derivatives with high selectivity and good functional group tolerance.
Furthermore, the catalytic aqueous solution could be reused for several times with high yields.
To achieve the goal of green chemistry, we established a low-cost catalytic system with both safety and environmental characteristics.
|