Synthesis Of Chalcones By Expandable Graphite As Catalyst Under Ultrasound Radiation

Chalcones are important natural compound of organic synthesis, and chalcones are used as important precursors in the synthesis of flavone's derivatives. This kind of compounds possesses many meditative activities and bioactivities. They have the functions of anti-cancer, anti-oxidize, anti-virus, anti-bacterium and so on. Chalcones are good natural medicine with rare poisonous effect. They have particularly treatment to stomach cancer. Many of chalcones could be used as organic non-linear optical materials due to their SHG activity. They could be applied in manufacturing laser machine because of the special absorption to ultraviolet radiation. Hydrogenous chalcone is a kind of natural sweetening. It is of about 1000 times sweeter than saccharose, about 3 to 5 times sweeter than saccharin, and it has no poisonous effect to human body. It is a good sweetening for diabetics to enhance their living standards.Chalcones could be prepared through condensation of acetophenones with benzaldehydes. To prepare chalcones, base or acid, such as NaOH KOH and HC1, are used as catalysts. However, the vice-reactions are so many, the yield is too low and all of these catalysts might erode equipment, pollute environment. Many chemists devote themselves to finding new catalyst for this reaction. Expandable graphite is a good catalyst to the synthesis of ester and the synthesis of acetals(ketals). There is few report of research in synthesizing chalcones using expandable graphite as catalyst.Our work is to find the method of preparing expandable graphite, which has the better catalyst effect to this reaction. Six chalcones had been synthesized using expandable graphite as catalyst under ultrasonic radiation. And the best reaction conditions had been found.The main work of this thesis:1. Using 50 mesh (320um), 80 mesh (200um), 100 mesh (160um) flake graphite as raw materials to prepare expandable graphite. And the super-fine expanded graphite had been made for the first time.2. The structure of expandable graphite had been measured by UV, SEM, STM, IRand XRD.3. Six chalcones have been synthesized using expandable graphite as catalyst under ultrasonic radiation.4. The structure of chalcones had been measured by melting point, IR, UV and elemental analysis. And the catalyst mechanisms had been researched roughly.