有机化学 ›› 2011, Vol. 31 ›› Issue (11): 1828-1834. 上一篇    下一篇

研究论文

SiO2固载咪唑基手性硫醚钯(II)催化剂的合成及其在Suzuki反应中的应用

毛璞*1,2,杨亮茹2,刘秀君2,蔡雅静2,赵成磊2,宋毛平*1   

  1. (1郑州大学化学系 郑州 450052)
    (2河南工业大学化学化工学院 郑州 450001)
  • 收稿日期:2011-03-24 修回日期:2011-05-12 发布日期:2011-06-14
  • 通讯作者: 毛璞 E-mail:liuxiujun0@126.com

Synthesis and Application in Suzuki Reaction of SiO2-Supported Chiral Imidazole Thioether Ligand Palladium Catalyst

Mao Pu*1,2 Yang Liangru2 Liu Xiu-jun2 Cai Yajing2 Zhao Chenglei2 Song Maoping*1   

  1. (1 Department of Chemistry, Zhengzhou University, Zhengzhou 450052)
    (2 School of Chemistry and Chemical Engineering, Henan University of Tech-nology, Zhengzhou 450001)
  • Received:2011-03-24 Revised:2011-05-12 Published:2011-06-14
  • Contact: Mao Pu E-mail:liuxiujun0@126.com

以L-缬氨酸、L-亮氨酸和L-苯丙氨酸为原料合成了未见报道的4种咪唑基手性硫醚化合物, 并将咪唑基硫醚固载到SiO2上制备了二氧化硅固载咪唑基手性硫醚配体, 用元素分析、热重等手段进行了表征|进而与PdCl2反应得到二氧化硅固载咪唑基手性硫醚-钯(II)催化剂, 用XPS等方法对其进行了表征. 考察了该催化剂在Suzuki反应中的催化性能. 结果表明, 在以溴苯与苯硼酸为底物的Suzuki反应中, 该催化剂用量为底物的0.75%、反应时间为5 h、温度为80 ℃时, 溴苯的转化率可达95%.

关键词: 咪唑基手性硫醚配体, 固载钯催化剂, Suzuki反应

Using L-valine, L-leucine, L-phenylalanine as starting materials, the imidazole ring was condensed by ring fragments and hydroxyl group was induced by the reduction of carboxyl of the amino acids. And then through chlorination and subsequent substitution by thiols, chiral imidazole thioethers were synthesized and their structures were characterized by 1H NMR, 13C NMR, IR and HRMS. Using SiO2 as a carrier, chiral imidazole thioethers were loaded and they were characterized by the DTA and elemental analysis. The results showed that the covalent bond was formed between thioether and silica. SiO2-supported chiral imidazole thioether ligands were separately coordinated to PdCl2 and the catalysts were characterized by XPS. The results showed that the palladium was coordinated with SiO2-supported chiral imidazole thiother ligand which can stabilize the catalyst, and the carbene might participate in the coordination with Pd. The activity of the catalysts was studied in the Suzuki coupling reaction. Under the optimum reaction conditions, which the reaction temperature was 80 ℃ and the amount of the catalyst was 0.75% of the substrate, the conversion of brombenzene was 95% for 5 h.

Key words: chiral midazole thioether ligand, supported Pd catalyst, Suzuki reaction