核桃壳粉负载纳米Cu催化剂的制备及催化炔酮合成

Preparation of Walnut Shell Powders-supported Cu Nanoparticles and Its Application in Ynones Synthesis

以核桃壳粉(WSPs)为载体,采用还原沉淀法制备了WSPs负载的铜催化剂(WSPs-Cu),采用红外(FT-IR)、热重分析(TGA)、X射线衍射分析(XRD)、扫描电镜结合X射线能谱(SEM/EDS)等对WSPs-Cu进行表征,结果表明:成功制备出Cu较均匀分布在WSPs表面的WSPs-Cu催化剂,WSPs-Cu的含铜量为3.386%,同时WSPs-Cu在100～200℃范围内具有较好的热稳定性。以WSPs-Cu为异相催化剂,催化苯甲酰氯及其衍生物与苯乙炔之间的偶联反应,制备出炔酮类化合物,结果表明:在无溶剂的条件下,以三乙胺为缚酸剂,微波辐射以及40℃下反应30 min,WSPs-Cu催化合成了5种炔酮化合物(产率61%～90%)。WSPs-Cu循环使用5次后仍保留较高活性,催化合成产物的产率为79%。将模型反应由微量放大到常量,投料量为80 mmol时,WSPs-Cu催化合成炔酮的产率可达到82%。

Walnut shell powders(WSPs), which were grinded from walnut shell, was used as supporter for the preparation of WSPs-supported copper catalyst(WSPs-Cu) by adsorption method. The heterogeneous catalyst WSPs-Cu was characterized by FT-IR, thermogravimetric analysis(TGA), X-ray diffraction analysis(XRD) and scanning electron microscopy/energy dispersive X-ray spectroscopy(SEM/EDS). The results showed that the WSPs-Cu catalyst was successfully prepared by this method. Copper were well distributed on the surface of WSPs. The copper content of the catalyst was 3.386% with good thermal stability within 100-200 ℃. The WSPs-Cu catalyst was used to prepare five ynones from benzoyl chloride derivatives and phenylacetylene via copper-catalyzed coupling reaction. The results revealed that ynones were synthesized under microwave irradiation and solvent-free conditions for 30 min at 40 ℃ by using triethylamine as acid-binding agent (61%-90%). The recyclability of WSPs-Cu was studied. It was found that the WSPs-Cu has high activity after using for five times and the yield was 79%. As the model reaction was amplified from trace to constant and the dosage of substrate was 80 mmol ,the yield of ynone catalyzed by WSPs-Cu reached 82%.