含氨基酸侧链的有机硅高分子催化剂(ⅩⅧ)——聚γ-(甘-谷氨酰胺基)丙基硅氧烷钯催化剂的合成及加氢活性

Studies on Polysiloxane Supported Catalysts with Amino Acid Side Chain (ⅩⅧ) ——The Synthesis and Hydrogenation Activity of Poly-γ-(glycyl-glutamine)propylsiloxane Palladium Catalysts

合成了不同N/Pd摩尔比的聚Y-(甘-谷氨酰胺基)丙基硅氧烷钯催化剂,表征了它们的结构。加氢实验表明,这种催化剂有很高的催化活性,对环戊二烯氢化分两步完成,对1,5-己二烯氢化则同时进行,讨论了溶剂。

The poly-γ-(glycyl-glutamine)propylsiloxane supported palladium catalysts with different N/Pd molar ratio were synthesized and characterized. The data of the differential IR spectra indicated that the polysiloxane with glyeyl-glutamine dipeptide side chain was taken shape in the ligand, XPS analysis shows that the activity center may be complex compound composed of the nitrogen of glyeyl-glutamine ligand and Pd atom in PdCl2. Besides, the palladium of catalyst appeared in the form of Pd(0) and Pd( I ). For a lot of substrates, the hydrogenation activity of the title complexes is high. The initial hydrogen absorption rate of acrylonitrile is-up to 3186 mL H2/min·mmol Pd on the catalyst with the N/Pd ratio of 21. 6. The hydrogenation of cyclopentadiene appeared to be a two-stage processi but in the 1,5-hexadiene case, the hydrogenation of two double bonds almost take place at the same time, though the reaction rates of both are different. The influences of the solvents and the molar ratio of N/Pd on catalytic activity were studied